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Java 11 migrate remaining q-r (#1121)

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* Moves queue-load-leveling to Java 11

* Moves reactor to Java 11

* Moves reader-writer-lock to Java 11

* Moves repository to Java 11

* Moves resource-acquisition-is-initialization to Java 11

* Moves retry to Java 11

* Moves role-object to Java 11
This commit is contained in:
Anurag Agarwal 2020-01-04 22:13:12 +05:30 committed by Ilkka Seppälä
parent cd2a2e7711
commit 20ea465b7f
52 changed files with 424 additions and 554 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
queue-load-leveling/src/main/java/com/iluwatar/queue/load/leveling/App.java
View File

@ -78,17 +78,17 @@ public class App {
try {
// Create a MessageQueue object.
MessageQueue msgQueue = new MessageQueue();
var msgQueue = new MessageQueue();
LOGGER.info("Submitting TaskGenerators and ServiceExecutor threads.");
// Create three TaskGenerator threads. Each of them will submit different number of jobs.
final Runnable taskRunnable1 = new TaskGenerator(msgQueue, 5);
final Runnable taskRunnable2 = new TaskGenerator(msgQueue, 1);
final Runnable taskRunnable3 = new TaskGenerator(msgQueue, 2);
final var taskRunnable1 = new TaskGenerator(msgQueue, 5);
final var taskRunnable2 = new TaskGenerator(msgQueue, 1);
final var taskRunnable3 = new TaskGenerator(msgQueue, 2);
// Create e service which should process the submitted jobs.
final Runnable srvRunnable = new ServiceExecutor(msgQueue);
final var srvRunnable = new ServiceExecutor(msgQueue);
// Create a ThreadPool of 2 threads and
// submit all Runnable task for execution to executor..

8
queue-load-leveling/src/main/java/com/iluwatar/queue/load/leveling/MessageQueue.java
View File

@ -40,7 +40,7 @@ public class MessageQueue {
// Default constructor when called creates Blocking Queue object.
public MessageQueue() {
this.blkQueue = new ArrayBlockingQueue<Message>(1024);
this.blkQueue = new ArrayBlockingQueue<>(1024);
}
/**
@ -62,13 +62,11 @@ public class MessageQueue {
* them. Retrieves and removes the head of this queue, or returns null if this queue is empty.
*/
public Message retrieveMsg() {
Message retrievedMsg = null;
try {
retrievedMsg = blkQueue.poll();
return blkQueue.poll();
} catch (Exception e) {
LOGGER.error(e.getMessage());
}
return retrievedMsg;
return null;
}
}

2
queue-load-leveling/src/main/java/com/iluwatar/queue/load/leveling/ServiceExecutor.java
View File

@ -46,7 +46,7 @@ public class ServiceExecutor implements Runnable {
public void run() {
try {
while (!Thread.currentThread().isInterrupted()) {
Message msg = msgQueue.retrieveMsg();
var msg = msgQueue.retrieveMsg();
if (null != msg) {
LOGGER.info(msg.toString() + " is served.");

5
queue-load-leveling/src/main/java/com/iluwatar/queue/load/leveling/TaskGenerator.java
View File

@ -63,12 +63,11 @@ public class TaskGenerator implements Task, Runnable {
* submission TaskGenerator thread will sleep for 1 second.
*/
public void run() {
int count = this.msgCount;
var count = this.msgCount;
try {
while (count > 0) {
String statusMsg = "Message-" + count + " submitted by " + Thread.currentThread().getName();
var statusMsg = "Message-" + count + " submitted by " + Thread.currentThread().getName();
this.submit(new Message(statusMsg));
LOGGER.info(statusMsg);

7
queue-load-leveling/src/test/java/com/iluwatar/queue/load/leveling/AppTest.java
View File

@ -25,15 +25,12 @@ package com.iluwatar.queue.load.leveling;
import org.junit.jupiter.api.Test;
import java.io.IOException;
/**
* Application Test
*/
public class AppTest {
@Test
public void test() throws IOException {
String[] args = {};
App.main(args);
public void test() {
App.main(new String[]{});
}
}

8
queue-load-leveling/src/test/java/com/iluwatar/queue/load/leveling/MessageQueueTest.java
View File

@ -23,21 +23,19 @@
package com.iluwatar.queue.load.leveling;
import org.junit.jupiter.api.Test;
import static org.junit.jupiter.api.Assertions.assertEquals;
import org.junit.jupiter.api.Test;
/**
*
* Test case for submitting and retrieving messages from Blocking Queue.
*
*/
public class MessageQueueTest {
@Test
public void messageQueueTest() {
MessageQueue msgQueue = new MessageQueue();
var msgQueue = new MessageQueue();
// submit message
msgQueue.submitMsg(new Message("MessageQueue Test"));

10
queue-load-leveling/src/test/java/com/iluwatar/queue/load/leveling/MessageTest.java
View File

@ -23,14 +23,12 @@
package com.iluwatar.queue.load.leveling;
import org.junit.jupiter.api.Test;
import static org.junit.jupiter.api.Assertions.assertEquals;
import org.junit.jupiter.api.Test;
/**
*
* Test case for creating and checking the Message.
*
*/
public class MessageTest {
@ -38,8 +36,8 @@ public class MessageTest {
public void messageTest() {
// Parameterized constructor test.
String testMsg = "Message Test";
Message msg = new Message(testMsg);
var testMsg = "Message Test";
var msg = new Message(testMsg);
assertEquals(testMsg, msg.getMsg());
}
}

16
queue-load-leveling/src/test/java/com/iluwatar/queue/load/leveling/TaskGenSrvExeTest.java
View File

@ -26,25 +26,23 @@ package com.iluwatar.queue.load.leveling;
import org.junit.jupiter.api.Test;
/**
*
* Test case for submitting Message to Blocking Queue by TaskGenerator
* and retrieve the message by ServiceExecutor.
*
* Test case for submitting Message to Blocking Queue by TaskGenerator and retrieve the message by
* ServiceExecutor.
*/
public class TaskGenSrvExeTest {
@Test
public void taskGeneratorTest() {
MessageQueue msgQueue = new MessageQueue();
var msgQueue = new MessageQueue();
// Create a task generator thread with 1 job to submit.
Runnable taskRunnable = new TaskGenerator(msgQueue, 1);
Thread taskGenThr = new Thread(taskRunnable);
var taskRunnable = new TaskGenerator(msgQueue, 1);
var taskGenThr = new Thread(taskRunnable);
taskGenThr.start();
// Create a service executor thread.
Runnable srvRunnable = new ServiceExecutor(msgQueue);
Thread srvExeThr = new Thread(srvRunnable);
var srvRunnable = new ServiceExecutor(msgQueue);
var srvExeThr = new Thread(srvRunnable);
srvExeThr.start();
}

14
reactor/src/main/java/com/iluwatar/reactor/app/App.java
View File

@ -124,15 +124,17 @@ public class App {
* This represents application specific business logic that dispatcher will call on appropriate
* events. These events are read events in our example.
*/
LoggingHandler loggingHandler = new LoggingHandler();
var loggingHandler = new LoggingHandler();
/*
* Our application binds to multiple channels and uses same logging handler to handle incoming
* log requests.
*/
reactor.registerChannel(tcpChannel(6666, loggingHandler))
reactor
.registerChannel(tcpChannel(6666, loggingHandler))
.registerChannel(tcpChannel(6667, loggingHandler))
.registerChannel(udpChannel(6668, loggingHandler)).start();
.registerChannel(udpChannel(6668, loggingHandler))
.start();
}
/**
@ -144,20 +146,20 @@ public class App {
public void stop() throws InterruptedException, IOException {
reactor.stop();
dispatcher.stop();
for (AbstractNioChannel channel : channels) {
for (var channel : channels) {
channel.getJavaChannel().close();
}
}
private AbstractNioChannel tcpChannel(int port, ChannelHandler handler) throws IOException {
NioServerSocketChannel channel = new NioServerSocketChannel(port, handler);
var channel = new NioServerSocketChannel(port, handler);
channel.bind();
channels.add(channel);
return channel;
}
private AbstractNioChannel udpChannel(int port, ChannelHandler handler) throws IOException {
NioDatagramChannel channel = new NioDatagramChannel(port, handler);
var channel = new NioDatagramChannel(port, handler);
channel.bind();
channels.add(channel);
return channel;

27
reactor/src/main/java/com/iluwatar/reactor/app/AppClient.java
View File

@ -25,7 +25,6 @@ package com.iluwatar.reactor.app;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
@ -55,7 +54,7 @@ public class AppClient {
* @throws IOException if any I/O error occurs.
*/
public static void main(String[] args) throws IOException {
AppClient appClient = new AppClient();
var appClient = new AppClient();
appClient.start();
}
@ -118,8 +117,8 @@ public class AppClient {
@Override
public void run() {
try (Socket socket = new Socket(InetAddress.getLocalHost(), serverPort)) {
OutputStream outputStream = socket.getOutputStream();
PrintWriter writer = new PrintWriter(outputStream);
var outputStream = socket.getOutputStream();
var writer = new PrintWriter(outputStream);
sendLogRequests(writer, socket.getInputStream());
} catch (IOException e) {
LOGGER.error("error sending requests", e);
@ -128,12 +127,12 @@ public class AppClient {
}
private void sendLogRequests(PrintWriter writer, InputStream inputStream) throws IOException {
for (int i = 0; i < 4; i++) {
for (var i = 0; i < 4; i++) {
writer.println(clientName + " - Log request: " + i);
writer.flush();
byte[] data = new byte[1024];
int read = inputStream.read(data, 0, data.length);
var data = new byte[1024];
var read = inputStream.read(data, 0, data.length);
if (read == 0) {
LOGGER.info("Read zero bytes");
} else {
@ -167,17 +166,17 @@ public class AppClient {
@Override
public void run() {
try (DatagramSocket socket = new DatagramSocket()) {
for (int i = 0; i < 4; i++) {
try (var socket = new DatagramSocket()) {
for (var i = 0; i < 4; i++) {
String message = clientName + " - Log request: " + i;
DatagramPacket request =
new DatagramPacket(message.getBytes(), message.getBytes().length, remoteAddress);
var message = clientName + " - Log request: " + i;
var bytes = message.getBytes();
var request = new DatagramPacket(bytes, bytes.length, remoteAddress);
socket.send(request);
byte[] data = new byte[1024];
DatagramPacket reply = new DatagramPacket(data, data.length);
var data = new byte[1024];
var reply = new DatagramPacket(data, data.length);
socket.receive(reply);
if (reply.getLength() == 0) {
LOGGER.info("Read zero bytes");

6
reactor/src/main/java/com/iluwatar/reactor/app/LoggingHandler.java
View File

@ -54,7 +54,7 @@ public class LoggingHandler implements ChannelHandler {
doLogging((ByteBuffer) readObject);
sendReply(channel, key);
} else if (readObject instanceof DatagramPacket) {
DatagramPacket datagram = (DatagramPacket) readObject;
var datagram = (DatagramPacket) readObject;
doLogging(datagram.getData());
sendReply(channel, datagram, key);
} else {
@ -71,14 +71,14 @@ public class LoggingHandler implements ChannelHandler {
* Create a reply acknowledgement datagram packet setting the receiver to the sender of incoming
* message.
*/
DatagramPacket replyPacket = new DatagramPacket(ByteBuffer.wrap(ACK));
var replyPacket = new DatagramPacket(ByteBuffer.wrap(ACK));
replyPacket.setReceiver(incomingPacket.getSender());
channel.write(replyPacket, key);
}
private static void sendReply(AbstractNioChannel channel, SelectionKey key) {
ByteBuffer buffer = ByteBuffer.wrap(ACK);
var buffer = ByteBuffer.wrap(ACK);
channel.write(buffer, key);
}

20
reactor/src/main/java/com/iluwatar/reactor/framework/AbstractNioChannel.java
View File

@ -46,8 +46,7 @@ public abstract class AbstractNioChannel {
private final SelectableChannel channel;
private final ChannelHandler handler;
private final Map<SelectableChannel, Queue<Object>> channelToPendingWrites =
new ConcurrentHashMap<>();
private final Map<SelectableChannel, Queue<Object>> channelToPendingWrites;
private NioReactor reactor;
/**
@ -59,6 +58,7 @@ public abstract class AbstractNioChannel {
public AbstractNioChannel(ChannelHandler handler, SelectableChannel channel) {
this.handler = handler;
this.channel = channel;
this.channelToPendingWrites = new ConcurrentHashMap<>();
}
/**
@ -117,18 +117,14 @@ public abstract class AbstractNioChannel {
* whole pending block of data at once.
*/
void flush(SelectionKey key) throws IOException {
Queue<Object> pendingWrites = channelToPendingWrites.get(key.channel());
while (true) {
Object pendingWrite = pendingWrites.poll();
if (pendingWrite == null) {
// We don't have anything more to write so channel is interested in reading more data
reactor.changeOps(key, SelectionKey.OP_READ);
break;
}
var pendingWrites = channelToPendingWrites.get(key.channel());
Object pendingWrite;
while ((pendingWrite = pendingWrites.poll()) != null) {
// ask the concrete channel to make sense of data and write it to java channel
doWrite(pendingWrite, key);
}
// We don't have anything more to write so channel is interested in reading more data
reactor.changeOps(key, SelectionKey.OP_READ);
}
/**
@ -162,7 +158,7 @@ public abstract class AbstractNioChannel {
* @param key the key which is writable.
*/
public void write(Object data, SelectionKey key) {
Queue<Object> pendingWrites = this.channelToPendingWrites.get(key.channel());
var pendingWrites = this.channelToPendingWrites.get(key.channel());
if (pendingWrites == null) {
synchronized (this.channelToPendingWrites) {
pendingWrites = this.channelToPendingWrites.get(key.channel());

8
reactor/src/main/java/com/iluwatar/reactor/framework/NioDatagramChannel.java
View File

@ -73,15 +73,15 @@ public class NioDatagramChannel extends AbstractNioChannel {
*/
@Override
public DatagramPacket read(SelectionKey key) throws IOException {
ByteBuffer buffer = ByteBuffer.allocate(1024);
SocketAddress sender = ((DatagramChannel) key.channel()).receive(buffer);
var buffer = ByteBuffer.allocate(1024);
var sender = ((DatagramChannel) key.channel()).receive(buffer);
/*
* It is required to create a DatagramPacket because we need to preserve which socket address
* acts as destination for sending reply packets.
*/
buffer.flip();
DatagramPacket packet = new DatagramPacket(buffer);
var packet = new DatagramPacket(buffer);
packet.setSender(sender);
return packet;
@ -115,7 +115,7 @@ public class NioDatagramChannel extends AbstractNioChannel {
*/
@Override
protected void doWrite(Object pendingWrite, SelectionKey key) throws IOException {
DatagramPacket pendingPacket = (DatagramPacket) pendingWrite;
var pendingPacket = (DatagramPacket) pendingWrite;
getJavaChannel().send(pendingPacket.getData(), pendingPacket.getReceiver());
}

34
reactor/src/main/java/com/iluwatar/reactor/framework/NioReactor.java
View File

@ -27,10 +27,7 @@ import java.io.IOException;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.util.Iterator;
import java.util.Queue;
import java.util.Set;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
@ -119,20 +116,15 @@ public class NioReactor {
* @throws IOException if any I/O error occurs.
*/
public NioReactor registerChannel(AbstractNioChannel channel) throws IOException {
SelectionKey key = channel.getJavaChannel().register(selector, channel.getInterestedOps());
var key = channel.getJavaChannel().register(selector, channel.getInterestedOps());
key.attach(channel);
channel.setReactor(this);
return this;
}
private void eventLoop() throws IOException {
while (true) {
// honor interrupt request
if (Thread.interrupted()) {
break;
}
while (!Thread.interrupted()) {
// honor any pending commands first
processPendingCommands();
@ -145,12 +137,11 @@ public class NioReactor {
/*
* Represents the events that have occurred on registered handles.
*/
Set<SelectionKey> keys = selector.selectedKeys();
Iterator<SelectionKey> iterator = keys.iterator();
var keys = selector.selectedKeys();
var iterator = keys.iterator();
while (iterator.hasNext()) {
SelectionKey key = iterator.next();
var key = iterator.next();
if (!key.isValid()) {
iterator.remove();
continue;
@ -162,9 +153,9 @@ public class NioReactor {
}
private void processPendingCommands() {
Iterator<Runnable> iterator = pendingCommands.iterator();
var iterator = pendingCommands.iterator();
while (iterator.hasNext()) {
Runnable command = iterator.next();
var command = iterator.next();
command.run();
iterator.remove();
}
@ -185,15 +176,14 @@ public class NioReactor {
}
private static void onChannelWritable(SelectionKey key) throws IOException {
AbstractNioChannel channel = (AbstractNioChannel) key.attachment();
var channel = (AbstractNioChannel) key.attachment();
channel.flush(key);
}
private void onChannelReadable(SelectionKey key) {
try {
// reads the incoming data in context of reactor main loop. Can this be improved?
Object readObject = ((AbstractNioChannel) key.attachment()).read(key);
var readObject = ((AbstractNioChannel) key.attachment()).read(key);
dispatchReadEvent(key, readObject);
} catch (IOException e) {
try {
@ -212,10 +202,10 @@ public class NioReactor {
}
private void onChannelAcceptable(SelectionKey key) throws IOException {
ServerSocketChannel serverSocketChannel = (ServerSocketChannel) key.channel();
SocketChannel socketChannel = serverSocketChannel.accept();
var serverSocketChannel = (ServerSocketChannel) key.channel();
var socketChannel = serverSocketChannel.accept();
socketChannel.configureBlocking(false);
SelectionKey readKey = socketChannel.register(selector, SelectionKey.OP_READ);
var readKey = socketChannel.register(selector, SelectionKey.OP_READ);
readKey.attach(key.attachment());
}

14
reactor/src/main/java/com/iluwatar/reactor/framework/NioServerSocketChannel.java
View File

@ -83,9 +83,9 @@ public class NioServerSocketChannel extends AbstractNioChannel {
*/
@Override
public ByteBuffer read(SelectionKey key) throws IOException {
SocketChannel socketChannel = (SocketChannel) key.channel();
ByteBuffer buffer = ByteBuffer.allocate(1024);
int read = socketChannel.read(buffer);
var socketChannel = (SocketChannel) key.channel();
var buffer = ByteBuffer.allocate(1024);
var read = socketChannel.read(buffer);
buffer.flip();
if (read == -1) {
throw new IOException("Socket closed");
@ -100,9 +100,9 @@ public class NioServerSocketChannel extends AbstractNioChannel {
*/
@Override
public void bind() throws IOException {
getJavaChannel().socket().bind(
new InetSocketAddress(InetAddress.getLocalHost(), port));
getJavaChannel().configureBlocking(false);
var javaChannel = getJavaChannel();
javaChannel.socket().bind(new InetSocketAddress(InetAddress.getLocalHost(), port));
javaChannel.configureBlocking(false);
LOGGER.info("Bound TCP socket at port: {}", port);
}
@ -112,7 +112,7 @@ public class NioServerSocketChannel extends AbstractNioChannel {
*/
@Override
protected void doWrite(Object pendingWrite, SelectionKey key) throws IOException {
ByteBuffer pendingBuffer = (ByteBuffer) pendingWrite;
var pendingBuffer = (ByteBuffer) pendingWrite;
((SocketChannel) key.channel()).write(pendingBuffer);
}
}

12
reactor/src/test/java/com/iluwatar/reactor/app/ReactorTest.java
View File

@ -25,14 +25,12 @@ package com.iluwatar.reactor.app;
import com.iluwatar.reactor.framework.SameThreadDispatcher;
import com.iluwatar.reactor.framework.ThreadPoolDispatcher;
import java.io.IOException;
import org.junit.jupiter.api.Test;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.IOException;
/**
*
* This class tests the Distributed Logging service by starting a Reactor and then sending it
* concurrent logging requests using multiple clients.
*/
@ -49,10 +47,10 @@ public class ReactorTest {
@Test
public void testAppUsingThreadPoolDispatcher() throws IOException, InterruptedException {
LOGGER.info("testAppUsingThreadPoolDispatcher start");
App app = new App(new ThreadPoolDispatcher(2));
var app = new App(new ThreadPoolDispatcher(2));
app.start();
AppClient client = new AppClient();
var client = new AppClient();
client.start();
// allow clients to send requests. Artificial delay.
@ -77,10 +75,10 @@ public class ReactorTest {
@Test
public void testAppUsingSameThreadDispatcher() throws IOException, InterruptedException {
LOGGER.info("testAppUsingSameThreadDispatcher start");
App app = new App(new SameThreadDispatcher());
var app = new App(new SameThreadDispatcher());
app.start();
AppClient client = new AppClient();
var client = new AppClient();
client.start();
// allow clients to send requests. Artificial delay.

27
reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/App.java
View File

@ -23,11 +23,9 @@
package com.iluwatar.reader.writer.lock;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.ThreadLocalRandom;
import java.util.concurrent.TimeUnit;
import java.util.stream.IntStream;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
@ -58,19 +56,21 @@ public class App {
*/
public static void main(String[] args) {
ExecutorService executeService = Executors.newFixedThreadPool(10);
ReaderWriterLock lock = new ReaderWriterLock();
var executeService = Executors.newFixedThreadPool(10);
var lock = new ReaderWriterLock();
// Start writers
IntStream.range(0, 5)
.forEach(i -> executeService.submit(new Writer("Writer " + i, lock.writeLock(),
ThreadLocalRandom.current().nextLong(5000))));
for (var i = 0; i < 5; i++) {
var writingTime = ThreadLocalRandom.current().nextLong(5000);
executeService.submit(new Writer("Writer " + i, lock.writeLock(), writingTime));
}
LOGGER.info("Writers added...");
// Start readers
IntStream.range(0, 5)
.forEach(i -> executeService.submit(new Reader("Reader " + i, lock.readLock(),
ThreadLocalRandom.current().nextLong(10))));
for (var i = 0; i < 5; i++) {
var readingTime = ThreadLocalRandom.current().nextLong(10);
executeService.submit(new Reader("Reader " + i, lock.readLock(), readingTime));
}
LOGGER.info("Readers added...");
try {
@ -81,9 +81,10 @@ public class App {
}
// Start readers
IntStream.range(6, 10)
.forEach(i -> executeService.submit(new Reader("Reader " + i, lock.readLock(),
ThreadLocalRandom.current().nextLong(10))));
for (var i = 6; i < 10; i++) {
var readingTime = ThreadLocalRandom.current().nextLong(10);
executeService.submit(new Reader("Reader " + i, lock.readLock(), readingTime));
}
LOGGER.info("More readers added...");

19
reader-writer-lock/src/main/java/com/iluwatar/reader/writer/lock/ReaderWriterLock.java
View File

@ -43,7 +43,7 @@ public class ReaderWriterLock implements ReadWriteLock {
private static final Logger LOGGER = LoggerFactory.getLogger(ReaderWriterLock.class);
private Object readerMutex = new Object();
private final Object readerMutex = new Object();
private int currentReaderCount;
@ -57,7 +57,7 @@ public class ReaderWriterLock implements ReadWriteLock {
*
* <p>This is the most important field in this class to control the access for reader/writer.
*/
private Set<Object> globalMutex = new HashSet<>();
private final Set<Object> globalMutex = new HashSet<>();
private ReadLock readerLock = new ReadLock();
private WriteLock writerLock = new WriteLock();
@ -114,8 +114,8 @@ public class ReaderWriterLock implements ReadWriteLock {
try {
globalMutex.wait();
} catch (InterruptedException e) {
LOGGER
.info("InterruptedException while waiting for globalMutex in acquireForReaders", e);
var message = "InterruptedException while waiting for globalMutex in acquireForReaders";
LOGGER.info(message, e);
Thread.currentThread().interrupt();
}
}
@ -125,7 +125,6 @@ public class ReaderWriterLock implements ReadWriteLock {
@Override
public void unlock() {
synchronized (readerMutex) {
currentReaderCount--;
// Release the lock only when it is the last reader, it is ensure that the lock is released
@ -142,7 +141,7 @@ public class ReaderWriterLock implements ReadWriteLock {
}
@Override
public void lockInterruptibly() throws InterruptedException {
public void lockInterruptibly() {
throw new UnsupportedOperationException();
}
@ -152,7 +151,7 @@ public class ReaderWriterLock implements ReadWriteLock {
}
@Override
public boolean tryLock(long time, TimeUnit unit) throws InterruptedException {
public boolean tryLock(long time, TimeUnit unit) {
throw new UnsupportedOperationException();
}
@ -170,7 +169,6 @@ public class ReaderWriterLock implements ReadWriteLock {
@Override
public void lock() {
synchronized (globalMutex) {
// Wait until the lock is free.
@ -189,7 +187,6 @@ public class ReaderWriterLock implements ReadWriteLock {
@Override
public void unlock() {
synchronized (globalMutex) {
globalMutex.remove(this);
// Notify the waiter, other writer or reader
@ -198,7 +195,7 @@ public class ReaderWriterLock implements ReadWriteLock {
}
@Override
public void lockInterruptibly() throws InterruptedException {
public void lockInterruptibly() {
throw new UnsupportedOperationException();
}
@ -208,7 +205,7 @@ public class ReaderWriterLock implements ReadWriteLock {
}
@Override
public boolean tryLock(long time, TimeUnit unit) throws InterruptedException {
public boolean tryLock(long time, TimeUnit unit) {
throw new UnsupportedOperationException();
}

5
reader-writer-lock/src/test/java/com/iluwatar/reader/writer/lock/AppTest.java
View File

@ -31,9 +31,8 @@ import org.junit.jupiter.api.Test;
public class AppTest {
@Test
public void test() throws Exception {
String[] args = {};
App.main(args);
public void test() {
App.main(new String[]{});
}
}

26
reader-writer-lock/src/test/java/com/iluwatar/reader/writer/lock/ReaderAndWriterTest.java
View File

@ -23,19 +23,17 @@
package com.iluwatar.reader.writer.lock;
import static org.junit.jupiter.api.Assertions.assertTrue;
import com.iluwatar.reader.writer.lock.utils.InMemoryAppender;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import static org.junit.jupiter.api.Assertions.assertTrue;
/**
* @author hongshuwei@gmail.com
*/
@ -61,12 +59,12 @@ public class ReaderAndWriterTest {
@Test
public void testReadAndWrite() throws Exception {
ReaderWriterLock lock = new ReaderWriterLock();
var lock = new ReaderWriterLock();
Reader reader1 = new Reader("Reader 1", lock.readLock());
Writer writer1 = new Writer("Writer 1", lock.writeLock());
var reader1 = new Reader("Reader 1", lock.readLock());
var writer1 = new Writer("Writer 1", lock.writeLock());
ExecutorService executeService = Executors.newFixedThreadPool(2);
var executeService = Executors.newFixedThreadPool(2);
executeService.submit(reader1);
// Let reader1 execute first
Thread.sleep(150);
@ -91,11 +89,11 @@ public class ReaderAndWriterTest {
@Test
public void testWriteAndRead() throws Exception {
ExecutorService executeService = Executors.newFixedThreadPool(2);
ReaderWriterLock lock = new ReaderWriterLock();
var executeService = Executors.newFixedThreadPool(2);
var lock = new ReaderWriterLock();
Reader reader1 = new Reader("Reader 1", lock.readLock());
Writer writer1 = new Writer("Writer 1", lock.writeLock());
var reader1 = new Reader("Reader 1", lock.readLock());
var writer1 = new Writer("Writer 1", lock.writeLock());
executeService.submit(writer1);
// Let writer1 execute first

20
reader-writer-lock/src/test/java/com/iluwatar/reader/writer/lock/ReaderTest.java
View File

@ -23,20 +23,18 @@
package com.iluwatar.reader.writer.lock;
import static org.junit.jupiter.api.Assertions.assertTrue;
import static org.mockito.Mockito.spy;
import com.iluwatar.reader.writer.lock.utils.InMemoryAppender;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import static org.junit.jupiter.api.Assertions.assertTrue;
import static org.mockito.Mockito.spy;
/**
* @author hongshuwei@gmail.com
*/
@ -62,11 +60,11 @@ public class ReaderTest {
@Test
public void testRead() throws Exception {
ExecutorService executeService = Executors.newFixedThreadPool(2);
ReaderWriterLock lock = new ReaderWriterLock();
var executeService = Executors.newFixedThreadPool(2);
var lock = new ReaderWriterLock();
Reader reader1 = spy(new Reader("Reader 1", lock.readLock()));
Reader reader2 = spy(new Reader("Reader 2", lock.readLock()));
var reader1 = spy(new Reader("Reader 1", lock.readLock()));
var reader2 = spy(new Reader("Reader 2", lock.readLock()));
executeService.submit(reader1);
Thread.sleep(150);

20
reader-writer-lock/src/test/java/com/iluwatar/reader/writer/lock/WriterTest.java
View File

@ -23,20 +23,18 @@
package com.iluwatar.reader.writer.lock;
import static org.junit.jupiter.api.Assertions.assertTrue;
import static org.mockito.Mockito.spy;
import com.iluwatar.reader.writer.lock.utils.InMemoryAppender;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import static org.junit.jupiter.api.Assertions.assertTrue;
import static org.mockito.Mockito.spy;
/**
* @author hongshuwei@gmail.com
*/
@ -62,11 +60,11 @@ public class WriterTest {
@Test
public void testWrite() throws Exception {
ExecutorService executeService = Executors.newFixedThreadPool(2);
ReaderWriterLock lock = new ReaderWriterLock();
var executeService = Executors.newFixedThreadPool(2);
var lock = new ReaderWriterLock();
Writer writer1 = spy(new Writer("Writer 1", lock.writeLock()));
Writer writer2 = spy(new Writer("Writer 2", lock.writeLock()));
var writer1 = spy(new Writer("Writer 1", lock.writeLock()));
var writer2 = spy(new Writer("Writer 2", lock.writeLock()));
executeService.submit(writer1);
// Let write1 execute first

3
reader-writer-lock/src/test/java/com/iluwatar/reader/writer/lock/utils/InMemoryAppender.java
View File

@ -26,10 +26,9 @@ package com.iluwatar.reader.writer.lock.utils;
import ch.qos.logback.classic.Logger;
import ch.qos.logback.classic.spi.ILoggingEvent;
import ch.qos.logback.core.AppenderBase;
import org.slf4j.LoggerFactory;
import java.util.LinkedList;
import java.util.List;
import org.slf4j.LoggerFactory;
/**
* InMemory Log Appender Util.

31
repository/src/main/java/com/iluwatar/repository/App.java
View File

@ -24,7 +24,6 @@
package com.iluwatar.repository;
import java.util.List;
import java.util.Optional;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.support.ClassPathXmlApplicationContext;
@ -55,14 +54,13 @@ public class App {
*/
public static void main(String[] args) {
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(
"applicationContext.xml");
PersonRepository repository = context.getBean(PersonRepository.class);
var context = new ClassPathXmlApplicationContext("applicationContext.xml");
var repository = context.getBean(PersonRepository.class);
Person peter = new Person("Peter", "Sagan", 17);
Person nasta = new Person("Nasta", "Kuzminova", 25);
Person john = new Person("John", "lawrence", 35);
Person terry = new Person("Terry", "Law", 36);
var peter = new Person("Peter", "Sagan", 17);
var nasta = new Person("Nasta", "Kuzminova", 25);
var john = new Person("John", "lawrence", 35);
var terry = new Person("Terry", "Law", 36);
// Add new Person records
repository.save(peter);
@ -74,17 +72,15 @@ public class App {
LOGGER.info("Count Person records: {}", repository.count());
// Print all records
List<Person> persons = (List<Person>) repository.findAll();
for (Person person : persons) {
LOGGER.info(person.toString());
}
var persons = (List<Person>) repository.findAll();
persons.stream().map(Person::toString).forEach(LOGGER::info);
// Update Person
nasta.setName("Barbora");
nasta.setSurname("Spotakova");
repository.save(nasta);
LOGGER.info("Find by id 2: {}", repository.findById(2L).get());
repository.findById(2L).ifPresent(p -> LOGGER.info("Find by id 2: {}", p));
// Remove record from Person
repository.deleteById(2L);
@ -93,16 +89,15 @@ public class App {
LOGGER.info("Count Person records: {}", repository.count());
// find by name
Optional<Person> p = repository.findOne(new PersonSpecifications.NameEqualSpec("John"));
LOGGER.info("Find by John is {}", p.get());
repository
.findOne(new PersonSpecifications.NameEqualSpec("John"))
.ifPresent(p -> LOGGER.info("Find by John is {}", p));
// find by age
persons = repository.findAll(new PersonSpecifications.AgeBetweenSpec(20, 40));
LOGGER.info("Find Person with age between 20,40: ");
for (Person person : persons) {
LOGGER.info(person.toString());
}
persons.stream().map(Person::toString).forEach(LOGGER::info);
repository.deleteAll();

42
repository/src/main/java/com/iluwatar/repository/AppConfig.java
View File

@ -25,7 +25,6 @@ package com.iluwatar.repository;
import java.sql.SQLException;
import java.util.List;
import java.util.Optional;
import java.util.Properties;
import javax.sql.DataSource;
import org.apache.commons.dbcp.BasicDataSource;
@ -55,7 +54,7 @@ public class AppConfig {
*/
@Bean(destroyMethod = "close")
public DataSource dataSource() {
BasicDataSource basicDataSource = new BasicDataSource();
var basicDataSource = new BasicDataSource();
basicDataSource.setDriverClassName("org.h2.Driver");
basicDataSource.setUrl("jdbc:h2:~/databases/person");
basicDataSource.setUsername("sa");
@ -68,13 +67,11 @@ public class AppConfig {
*/
@Bean
public LocalContainerEntityManagerFactoryBean entityManagerFactory() {
LocalContainerEntityManagerFactoryBean entityManager =
new LocalContainerEntityManagerFactoryBean();
var entityManager = new LocalContainerEntityManagerFactoryBean();
entityManager.setDataSource(dataSource());
entityManager.setPackagesToScan("com.iluwatar");
entityManager.setPersistenceProvider(new HibernatePersistenceProvider());
entityManager.setJpaProperties(jpaProperties());
return entityManager;
}
@ -82,7 +79,7 @@ public class AppConfig {
* Properties for Jpa.
*/
private static Properties jpaProperties() {
Properties properties = new Properties();
var properties = new Properties();
properties.setProperty("hibernate.dialect", "org.hibernate.dialect.H2Dialect");
properties.setProperty("hibernate.hbm2ddl.auto", "create-drop");
return properties;
@ -93,7 +90,7 @@ public class AppConfig {
*/
@Bean
public JpaTransactionManager transactionManager() throws SQLException {
JpaTransactionManager transactionManager = new JpaTransactionManager();
var transactionManager = new JpaTransactionManager();
transactionManager.setEntityManagerFactory(entityManagerFactory().getObject());
return transactionManager;
}
@ -104,15 +101,13 @@ public class AppConfig {
* @param args command line args
*/
public static void main(String[] args) {
var context = new AnnotationConfigApplicationContext(AppConfig.class);
var repository = context.getBean(PersonRepository.class);
AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(
AppConfig.class);
PersonRepository repository = context.getBean(PersonRepository.class);
Person peter = new Person("Peter", "Sagan", 17);
Person nasta = new Person("Nasta", "Kuzminova", 25);
Person john = new Person("John", "lawrence", 35);
Person terry = new Person("Terry", "Law", 36);
var peter = new Person("Peter", "Sagan", 17);
var nasta = new Person("Nasta", "Kuzminova", 25);
var john = new Person("John", "lawrence", 35);
var terry = new Person("Terry", "Law", 36);
// Add new Person records
repository.save(peter);
@ -124,17 +119,15 @@ public class AppConfig {
LOGGER.info("Count Person records: {}", repository.count());
// Print all records
List<Person> persons = (List<Person>) repository.findAll();
for (Person person : persons) {
LOGGER.info(person.toString());
}
var persons = (List<Person>) repository.findAll();
persons.stream().map(Person::toString).forEach(LOGGER::info);
// Update Person
nasta.setName("Barbora");
nasta.setSurname("Spotakova");
repository.save(nasta);
LOGGER.info("Find by id 2: {}", repository.findById(2L).get());
repository.findById(2L).ifPresent(p -> LOGGER.info("Find by id 2: {}", p));
// Remove record from Person
repository.deleteById(2L);
@ -143,16 +136,15 @@ public class AppConfig {
LOGGER.info("Count Person records: {}", repository.count());
// find by name
Optional<Person> p = repository.findOne(new PersonSpecifications.NameEqualSpec("John"));
LOGGER.info("Find by John is {}", p.get());
repository
.findOne(new PersonSpecifications.NameEqualSpec("John"))
.ifPresent(p -> LOGGER.info("Find by John is {}", p));
// find by age
persons = repository.findAll(new PersonSpecifications.AgeBetweenSpec(20, 40));
LOGGER.info("Find Person with age between 20,40: ");
for (Person person : persons) {
LOGGER.info(person.toString());
}
persons.stream().map(Person::toString).forEach(LOGGER::info);
context.close();

15
repository/src/main/java/com/iluwatar/repository/Person.java
View File

@ -92,9 +92,8 @@ public class Person {
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
final var prime = 31;
var result = 1;
result = prime * result + age;
result = prime * result + (id == null ? 0 : id.hashCode());
result = prime * result + (name == null ? 0 : name.hashCode());
@ -113,7 +112,7 @@ public class Person {
if (getClass() != obj.getClass()) {
return false;
}
Person other = (Person) obj;
var other = (Person) obj;
if (age != other.age) {
return false;
}
@ -132,13 +131,9 @@ public class Person {
return false;
}
if (surname == null) {
if (other.surname != null) {
return false;
return other.surname == null;
}
} else if (!surname.equals(other.surname)) {
return false;
}
return true;
return surname.equals(other.surname);
}
}

4
repository/src/main/java/com/iluwatar/repository/PersonSpecifications.java
View File

@ -50,9 +50,7 @@ public class PersonSpecifications {
@Override
public Predicate toPredicate(Root<Person> root, CriteriaQuery<?> query, CriteriaBuilder cb) {
return cb.between(root.get("age"), from, to);
}
}
@ -72,9 +70,7 @@ public class PersonSpecifications {
* Get predicate.
*/
public Predicate toPredicate(Root<Person> root, CriteriaQuery<?> query, CriteriaBuilder cb) {
return cb.equal(root.get("name"), this.name);
}
}

46
repository/src/test/java/com/iluwatar/repository/AnnotationBasedRepositoryTest.java
View File

@ -23,7 +23,13 @@
package com.iluwatar.repository;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNull;
import static org.junit.jupiter.api.Assertions.assertTrue;
import com.google.common.collect.Lists;
import java.util.List;
import javax.annotation.Resource;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
@ -31,16 +37,9 @@ import org.junit.jupiter.api.extension.ExtendWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit.jupiter.SpringExtension;
import javax.annotation.Resource;
import java.util.List;
import java.util.Optional;
import static org.junit.jupiter.api.Assertions.*;
/**
* Test case to test the functions of {@link PersonRepository}, beside the CRUD functions, the query
* by {@link org.springframework.data.jpa.domain.Specification} are also test.
*
*/
@ExtendWith(SpringExtension.class)
@SpringBootTest(classes = {AppConfig.class})
@ -49,33 +48,30 @@ public class AnnotationBasedRepositoryTest {
@Resource
private PersonRepository repository;
Person peter = new Person("Peter", "Sagan", 17);
Person nasta = new Person("Nasta", "Kuzminova", 25);
Person john = new Person("John", "lawrence", 35);
Person terry = new Person("Terry", "Law", 36);
private Person peter = new Person("Peter", "Sagan", 17);
private Person nasta = new Person("Nasta", "Kuzminova", 25);
private Person john = new Person("John", "lawrence", 35);
private Person terry = new Person("Terry", "Law", 36);
List<Person> persons = List.of(peter, nasta, john, terry);
private List<Person> persons = List.of(peter, nasta, john, terry);
/**
* Prepare data for test
*/
@BeforeEach
public void setup() {
repository.saveAll(persons);
}
@Test
public void testFindAll() {
List<Person> actuals = Lists.newArrayList(repository.findAll());
var actuals = Lists.newArrayList(repository.findAll());
assertTrue(actuals.containsAll(persons) && persons.containsAll(actuals));
}
@Test
public void testSave() {
Person terry = repository.findByName("Terry");
var terry = repository.findByName("Terry");
terry.setSurname("Lee");
terry.setAge(47);
repository.save(terry);
@ -87,8 +83,7 @@ public class AnnotationBasedRepositoryTest {
@Test
public void testDelete() {
Person terry = repository.findByName("Terry");
var terry = repository.findByName("Terry");
repository.delete(terry);
assertEquals(3, repository.count());
@ -97,31 +92,26 @@ public class AnnotationBasedRepositoryTest {
@Test
public void testCount() {
assertEquals(4, repository.count());
}
@Test
public void testFindAllByAgeBetweenSpec() {
List<Person> persons = repository.findAll(new PersonSpecifications.AgeBetweenSpec(20, 40));
var persons = repository.findAll(new PersonSpecifications.AgeBetweenSpec(20, 40));
assertEquals(3, persons.size());
assertTrue(persons.stream().allMatch((item) -> {
return item.getAge() > 20 && item.getAge() < 40;
}));
assertTrue(persons.stream().allMatch((item) -> item.getAge() > 20 && item.getAge() < 40));
}
@Test
public void testFindOneByNameEqualSpec() {
Optional<Person> actual = repository.findOne(new PersonSpecifications.NameEqualSpec("Terry"));
var actual = repository.findOne(new PersonSpecifications.NameEqualSpec("Terry"));
assertTrue(actual.isPresent());
assertEquals(terry, actual.get());
}
@AfterEach
public void cleanup() {
repository.deleteAll();
}

19
repository/src/test/java/com/iluwatar/repository/AppConfigTest.java
View File

@ -23,6 +23,12 @@
package com.iluwatar.repository;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNotNull;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.sql.DataSource;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.springframework.beans.factory.annotation.Autowired;
@ -30,16 +36,8 @@ import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit.jupiter.SpringExtension;
import org.springframework.transaction.annotation.Transactional;
import javax.sql.DataSource;
import java.sql.ResultSet;
import java.sql.SQLException;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNotNull;
/**
* This case is Just for test the Annotation Based configuration
*
*/
@ExtendWith(SpringExtension.class)
@SpringBootTest(classes = {AppConfig.class})
@ -62,12 +60,11 @@ public class AppConfigTest {
@Test
@Transactional
public void testQuery() throws SQLException {
ResultSet resultSet = dataSource.getConnection().createStatement().executeQuery("SELECT 1");
var resultSet = dataSource.getConnection().createStatement().executeQuery("SELECT 1");
var expected = "1";
String result = null;
String expected = "1";
while (resultSet.next()) {
result = resultSet.getString(1);
}
assertEquals(expected, result);
}

5
repository/src/test/java/com/iluwatar/repository/AppTest.java
View File

@ -25,15 +25,12 @@ package com.iluwatar.repository;
import org.junit.jupiter.api.Test;
import java.io.IOException;
/**
* Tests that Repository example runs without errors.
*/
public class AppTest {
@Test
public void test() {
String[] args = {};
App.main(args);
App.main(new String[]{});
}
}

41
repository/src/test/java/com/iluwatar/repository/RepositoryTest.java
View File

@ -23,7 +23,13 @@
package com.iluwatar.repository;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNull;
import static org.junit.jupiter.api.Assertions.assertTrue;
import com.google.common.collect.Lists;
import java.util.List;
import javax.annotation.Resource;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
@ -31,12 +37,6 @@ import org.junit.jupiter.api.extension.ExtendWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit.jupiter.SpringExtension;
import javax.annotation.Resource;
import java.util.List;
import java.util.Optional;
import static org.junit.jupiter.api.Assertions.*;
/**
* Test case to test the functions of {@link PersonRepository}, beside the CRUD functions, the query
* by {@link org.springframework.data.jpa.domain.Specification} are also test.
@ -48,33 +48,30 @@ public class RepositoryTest {
@Resource
private PersonRepository repository;
Person peter = new Person("Peter", "Sagan", 17);
Person nasta = new Person("Nasta", "Kuzminova", 25);
Person john = new Person("John", "lawrence", 35);
Person terry = new Person("Terry", "Law", 36);
private Person peter = new Person("Peter", "Sagan", 17);
private Person nasta = new Person("Nasta", "Kuzminova", 25);
private Person john = new Person("John", "lawrence", 35);
private Person terry = new Person("Terry", "Law", 36);
List<Person> persons = List.of(peter, nasta, john, terry);
private List<Person> persons = List.of(peter, nasta, john, terry);
/**
* Prepare data for test
*/
@BeforeEach
public void setup() {
repository.saveAll(persons);
}
@Test
public void testFindAll() {
List<Person> actuals = Lists.newArrayList(repository.findAll());
var actuals = Lists.newArrayList(repository.findAll());
assertTrue(actuals.containsAll(persons) && persons.containsAll(actuals));
}
@Test
public void testSave() {
Person terry = repository.findByName("Terry");
var terry = repository.findByName("Terry");
terry.setSurname("Lee");
terry.setAge(47);
repository.save(terry);
@ -86,8 +83,7 @@ public class RepositoryTest {
@Test
public void testDelete() {
Person terry = repository.findByName("Terry");
var terry = repository.findByName("Terry");
repository.delete(terry);
assertEquals(3, repository.count());
@ -96,14 +92,12 @@ public class RepositoryTest {
@Test
public void testCount() {
assertEquals(4, repository.count());
}
@Test
public void testFindAllByAgeBetweenSpec() {
List<Person> persons = repository.findAll(new PersonSpecifications.AgeBetweenSpec(20, 40));
var persons = repository.findAll(new PersonSpecifications.AgeBetweenSpec(20, 40));
assertEquals(3, persons.size());
assertTrue(persons.stream().allMatch(item -> item.getAge() > 20 && item.getAge() < 40));
@ -111,14 +105,13 @@ public class RepositoryTest {
@Test
public void testFindOneByNameEqualSpec() {
Optional<Person> actual = repository.findOne(new PersonSpecifications.NameEqualSpec("Terry"));
var actual = repository.findOne(new PersonSpecifications.NameEqualSpec("Terry"));
assertTrue(actual.isPresent());
assertEquals(terry, actual.get());
}
@AfterEach
public void cleanup() {
repository.deleteAll();
}

4
resource-acquisition-is-initialization/src/main/java/com/iluwatar/resource/acquisition/is/initialization/App.java
View File

@ -54,11 +54,11 @@ public class App {
*/
public static void main(String[] args) throws Exception {
try (SlidingDoor slidingDoor = new SlidingDoor()) {
try (var ignored = new SlidingDoor()) {
LOGGER.info("Walking in.");
}
try (TreasureChest treasureChest = new TreasureChest()) {
try (var ignored = new TreasureChest()) {
LOGGER.info("Looting contents.");
}
}

2
resource-acquisition-is-initialization/src/main/java/com/iluwatar/resource/acquisition/is/initialization/SlidingDoor.java
View File

@ -38,7 +38,7 @@ public class SlidingDoor implements AutoCloseable {
}
@Override
public void close() throws Exception {
public void close() {
LOGGER.info("Sliding door closes.");
}
}

3
resource-acquisition-is-initialization/src/main/java/com/iluwatar/resource/acquisition/is/initialization/TreasureChest.java
View File

@ -24,7 +24,6 @@
package com.iluwatar.resource.acquisition.is.initialization;
import java.io.Closeable;
import java.io.IOException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
@ -40,7 +39,7 @@ public class TreasureChest implements Closeable {
}
@Override
public void close() throws IOException {
public void close() {
LOGGER.info("Treasure chest closes.");
}
}

5
resource-acquisition-is-initialization/src/test/java/com/iluwatar/resource/acquisition/is/initialization/AppTest.java
View File

@ -26,15 +26,12 @@ package com.iluwatar.resource.acquisition.is.initialization;
import org.junit.jupiter.api.Test;
/**
*
* Application test
*
*/
public class AppTest {
@Test
public void test() throws Exception {
String[] args = {};
App.main(args);
App.main(new String[]{});
}
}

9
resource-acquisition-is-initialization/src/test/java/com/iluwatar/resource/acquisition/is/initialization/ClosableTest.java
View File

@ -23,19 +23,18 @@
package com.iluwatar.resource.acquisition.is.initialization;
import static org.junit.jupiter.api.Assertions.assertTrue;
import ch.qos.logback.classic.Logger;
import ch.qos.logback.classic.spi.ILoggingEvent;
import ch.qos.logback.core.AppenderBase;
import java.util.LinkedList;
import java.util.List;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.slf4j.LoggerFactory;
import static org.junit.jupiter.api.Assertions.assertTrue;
/**
* Date: 12/28/15 - 9:31 PM
*
@ -56,8 +55,8 @@ public class ClosableTest {
}
@Test
public void testOpenClose() throws Exception {
try (final SlidingDoor door = new SlidingDoor(); final TreasureChest chest = new TreasureChest()) {
public void testOpenClose() {
try (final var ignored = new SlidingDoor(); final var ignored1 = new TreasureChest()) {
assertTrue(appender.logContains("Sliding door opens."));
assertTrue(appender.logContains("Treasure chest opens."));
}

4
retry/README.md
View File

@ -78,7 +78,7 @@ to recover from this error.
We can model a 'recoverable' scenario by instantiating `FindCustomer` like this:
```java
final BusinessOperation<String> op = new FindCustomer(
final var op = new FindCustomer(
"12345",
new CustomerNotFoundException("not found"),
new CustomerNotFoundException("still not found"),
@ -97,7 +97,7 @@ worker thread in the database subsystem typically needs 50ms to
this:
```java
final BusinessOperation<String> op = new Retry<>(
final var op = new Retry<>(
new FindCustomer(
"1235",
new CustomerNotFoundException("not found"),

8
retry/src/main/java/com/iluwatar/retry/App.java
View File

@ -90,14 +90,14 @@ public final class App {
}
private static void errorWithRetry() throws Exception {
final Retry<String> retry = new Retry<>(
final var retry = new Retry<>(
new FindCustomer("123", new CustomerNotFoundException("not found")),
3, //3 attempts
100, //100 ms delay between attempts
e -> CustomerNotFoundException.class.isAssignableFrom(e.getClass())
);
op = retry;
final String customerId = op.perform();
final var customerId = op.perform();
LOG.info(String.format(
"However, retrying the operation while ignoring a recoverable error will eventually yield "
+ "the result %s after a number of attempts %s", customerId, retry.attempts()
@ -105,14 +105,14 @@ public final class App {
}
private static void errorWithRetryExponentialBackoff() throws Exception {
final RetryExponentialBackoff<String> retry = new RetryExponentialBackoff<>(
final var retry = new RetryExponentialBackoff<>(
new FindCustomer("123", new CustomerNotFoundException("not found")),
6, //6 attempts
30000, //30 s max delay between attempts
e -> CustomerNotFoundException.class.isAssignableFrom(e.getClass())
);
op = retry;
final String customerId = op.perform();
final var customerId = op.perform();
LOG.info(String.format(
"However, retrying the operation while ignoring a recoverable error will eventually yield "
+ "the result %s after a number of attempts %s", customerId, retry.attempts()

4
retry/src/main/java/com/iluwatar/retry/RetryExponentialBackoff.java
View File

@ -100,8 +100,8 @@ public final class RetryExponentialBackoff<T> implements BusinessOperation<T> {
}
try {
long testDelay = (long) Math.pow(2, this.attempts()) * 1000 + RANDOM.nextInt(1000);
long delay = testDelay < this.maxDelay ? testDelay : maxDelay;
var testDelay = (long) Math.pow(2, this.attempts()) * 1000 + RANDOM.nextInt(1000);
var delay = Math.min(testDelay, this.maxDelay);
Thread.sleep(delay);
} catch (InterruptedException f) {
//ignore

21
retry/src/test/java/com/iluwatar/retry/FindCustomerTest.java
View File

@ -23,12 +23,12 @@
package com.iluwatar.retry;
import org.junit.jupiter.api.Test;
import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.junit.jupiter.api.Assertions.assertThrows;
import org.junit.jupiter.api.Test;
/**
* Unit tests for {@link FindCustomer}.
*
@ -40,10 +40,7 @@ public class FindCustomerTest {
*/
@Test
public void noExceptions() throws Exception {
assertThat(
new FindCustomer("123").perform(),
is("123")
);
assertThat(new FindCustomer("123").perform(), is("123"));
}
/**
@ -53,9 +50,8 @@ public class FindCustomerTest {
*/
@Test
public void oneException() {
assertThrows(BusinessException.class, () -> {
new FindCustomer("123", new BusinessException("test")).perform();
});
var findCustomer = new FindCustomer("123", new BusinessException("test"));
assertThrows(BusinessException.class, findCustomer::perform);
}
/**
@ -65,7 +61,7 @@ public class FindCustomerTest {
*/
@Test
public void resultAfterExceptions() throws Exception {
final BusinessOperation<String> op = new FindCustomer(
final var op = new FindCustomer(
"123",
new CustomerNotFoundException("not found"),
new DatabaseNotAvailableException("not available")
@ -81,9 +77,6 @@ public class FindCustomerTest {
//ignore
}
assertThat(
op.perform(),
is("123")
);
assertThat(op.perform(), is("123"));
}
}

38
retry/src/test/java/com/iluwatar/retry/RetryExponentialBackoffTest.java
View File

@ -23,11 +23,12 @@
package com.iluwatar.retry;
import org.junit.jupiter.api.Test;
import static org.hamcrest.CoreMatchers.hasItem;
import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.MatcherAssert.assertThat;
import org.junit.jupiter.api.Test;
/**
* Unit tests for {@link Retry}.
*
@ -38,9 +39,9 @@ public class RetryExponentialBackoffTest {
* Should contain all errors thrown.
*/
@Test
public void errors() throws Exception {
final BusinessException e = new BusinessException("unhandled");
final RetryExponentialBackoff<String> retry = new RetryExponentialBackoff<>(
public void errors() {
final var e = new BusinessException("unhandled");
final var retry = new RetryExponentialBackoff<String>(
() -> {
throw e;
},
@ -53,10 +54,7 @@ public class RetryExponentialBackoffTest {
//ignore
}
assertThat(
retry.errors(),
hasItem(e)
);
assertThat(retry.errors(), hasItem(e));
}
/**
@ -65,8 +63,8 @@ public class RetryExponentialBackoffTest {
*/
@Test
public void attempts() {
final BusinessException e = new BusinessException("unhandled");
final RetryExponentialBackoff<String> retry = new RetryExponentialBackoff<>(
final var e = new BusinessException("unhandled");
final var retry = new RetryExponentialBackoff<String>(
() -> {
throw e;
},
@ -79,20 +77,17 @@ public class RetryExponentialBackoffTest {
//ignore
}
assertThat(
retry.attempts(),
is(1)
);
assertThat(retry.attempts(), is(1));
}
/**
* Final number of attempts should be equal to the number of attempts asked because we are
* asking it to ignore the exception that will be thrown.
* Final number of attempts should be equal to the number of attempts asked because we are asking
* it to ignore the exception that will be thrown.
*/
@Test
public void ignore() throws Exception {
final BusinessException e = new CustomerNotFoundException("customer not found");
final RetryExponentialBackoff<String> retry = new RetryExponentialBackoff<>(
public void ignore() {
final var e = new CustomerNotFoundException("customer not found");
final var retry = new RetryExponentialBackoff<String>(
() -> {
throw e;
},
@ -106,9 +101,6 @@ public class RetryExponentialBackoffTest {
//ignore
}
assertThat(
retry.attempts(),
is(2)
);
assertThat(retry.attempts(), is(2));
}
}

46
retry/src/test/java/com/iluwatar/retry/RetryTest.java
View File

@ -23,12 +23,12 @@
package com.iluwatar.retry;
import org.junit.jupiter.api.Test;
import static org.hamcrest.CoreMatchers.hasItem;
import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.MatcherAssert.assertThat;
import org.junit.jupiter.api.Test;
/**
* Unit tests for {@link Retry}.
*
@ -40,10 +40,11 @@ public class RetryTest {
*/
@Test
public void errors() {
final BusinessException e = new BusinessException("unhandled");
final Retry<String> retry = new Retry<>(
final var e = new BusinessException("unhandled");
final var retry = new Retry<String>(
() -> {
throw e; },
throw e;
},
2,
0
);
@ -53,10 +54,7 @@ public class RetryTest {
//ignore
}
assertThat(
retry.errors(),
hasItem(e)
);
assertThat(retry.errors(), hasItem(e));
}
/**
@ -65,10 +63,11 @@ public class RetryTest {
*/
@Test
public void attempts() {
final BusinessException e = new BusinessException("unhandled");
final Retry<String> retry = new Retry<>(
final var e = new BusinessException("unhandled");
final var retry = new Retry<String>(
() -> {
throw e; },
throw e;
},
2,
0
);
@ -78,22 +77,20 @@ public class RetryTest {
//ignore
}
assertThat(
retry.attempts(),
is(1)
);
assertThat(retry.attempts(), is(1));
}
/**
* Final number of attempts should be equal to the number of attempts asked because we are
* asking it to ignore the exception that will be thrown.
* Final number of attempts should be equal to the number of attempts asked because we are asking
* it to ignore the exception that will be thrown.
*/
@Test
public void ignore() throws Exception {
final BusinessException e = new CustomerNotFoundException("customer not found");
final Retry<String> retry = new Retry<>(
public void ignore() {
final var e = new CustomerNotFoundException("customer not found");
final var retry = new Retry<String>(
() -> {
throw e; },
throw e;
},
2,
0,
ex -> CustomerNotFoundException.class.isAssignableFrom(ex.getClass())
@ -104,10 +101,7 @@ public class RetryTest {
//ignore
}
assertThat(
retry.attempts(),
is(2)
);
assertThat(retry.attempts(), is(2));
}
}

58
role-object/src/main/java/com/iluwatar/roleobject/ApplicationRoleObject.java
View File

@ -30,37 +30,31 @@ import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* The Role Object pattern suggests to model context-specific views
* of an object as separate role objects which are
* dynamically attached to and removed from the core object.
* We call the resulting composite object structure,
* consisting of the core and its role objects, a subject.
* A subject often plays several roles and the same role is likely to
* be played by different subjects.
* As an example consider two different customers playing the role of borrower and
* investor, respectively. Both roles could as well be played by a single {@link Customer} object.
* The common superclass for customer-specific roles is provided by {@link CustomerRole},
* which also supports the {@link Customer} interface.
* The Role Object pattern suggests to model context-specific views of an object as separate role
* objects which are dynamically attached to and removed from the core object. We call the resulting
* composite object structure, consisting of the core and its role objects, a subject. A subject
* often plays several roles and the same role is likely to be played by different subjects. As an
* example consider two different customers playing the role of borrower and investor, respectively.
* Both roles could as well be played by a single {@link Customer} object. The common superclass for
* customer-specific roles is provided by {@link CustomerRole}, which also supports the {@link
* Customer} interface.
*
* <p>The {@link CustomerRole} class is abstract and not meant to be instantiated.
* Concrete subclasses of {@link CustomerRole}, for example {@link BorrowerRole}
* or {@link InvestorRole}, define and implement the interface for specific roles. It is only
* these subclasses which are instantiated at runtime.
* The {@link BorrowerRole} class defines the context-specific view of {@link Customer}
* objects as needed by the loan department.
* It defines additional operations to manage the customer’s
* credits and securities. Similarly, the {@link InvestorRole} class adds operations specific
* to the investment department’s view of customers.
* A client like the loan application may either work with objects of the {@link CustomerRole}
* class, using the interface class {@link Customer}, or with objects of concrete
* {@link CustomerRole} subclasses. Suppose the loan application knows a particular
* {@link Customer} instance through its {@link Customer} interface. The loan application
* may want to check whether the {@link Customer} object plays the role of Borrower.
* To this end it calls {@link Customer#hasRole(Role)} with a suitable role specification. For
* the purpose of our example, let’s assume we can name roles with enum.
* If the {@link Customer} object can play the role named “Borrower,” the loan application will
* ask it to return a reference to the corresponding object.
* The loan application may now use this reference to call Borrower-specific operations.
* Concrete subclasses of {@link CustomerRole}, for example {@link BorrowerRole} or {@link
* InvestorRole}, define and implement the interface for specific roles. It is only these subclasses
* which are instantiated at runtime. The {@link BorrowerRole} class defines the context-specific
* view of {@link Customer} objects as needed by the loan department. It defines additional
* operations to manage the customer’s credits and securities. Similarly, the {@link InvestorRole}
* class adds operations specific to the investment department’s view of customers. A client like
* the loan application may either work with objects of the {@link CustomerRole} class, using the
* interface class {@link Customer}, or with objects of concrete {@link CustomerRole} subclasses.
* Suppose the loan application knows a particular {@link Customer} instance through its {@link
* Customer} interface. The loan application may want to check whether the {@link Customer} object
* plays the role of Borrower. To this end it calls {@link Customer#hasRole(Role)} with a suitable
* role specification. For the purpose of our example, let’s assume we can name roles with enum. If
* the {@link Customer} object can play the role named “Borrower,” the loan application will ask it
* to return a reference to the corresponding object. The loan application may now use this
* reference to call Borrower-specific operations.
*/
public class ApplicationRoleObject {
@ -72,13 +66,13 @@ public class ApplicationRoleObject {
* @param args program arguments
*/
public static void main(String[] args) {
Customer customer = Customer.newCustomer(Borrower, Investor);
var customer = Customer.newCustomer(Borrower, Investor);
logger.info(" the new customer created : {}", customer);
boolean hasBorrowerRole = customer.hasRole(Borrower);
var hasBorrowerRole = customer.hasRole(Borrower);
logger.info(" customer has a borrowed role - {}", hasBorrowerRole);
boolean hasInvestorRole = customer.hasRole(Investor);
var hasInvestorRole = customer.hasRole(Investor);
logger.info(" customer has an investor role - {}", hasInvestorRole);
customer.getRole(Investor, InvestorRole.class)

12
role-object/src/main/java/com/iluwatar/roleobject/Customer.java
View File

@ -23,6 +23,7 @@
package com.iluwatar.roleobject;
import java.util.Arrays;
import java.util.Optional;
/**
@ -32,6 +33,7 @@ public abstract class Customer {
/**
* Add specific role @see {@link Role}.
*
* @param role to add
* @return true if the operation has been successful otherwise false
*/
@ -39,6 +41,7 @@ public abstract class Customer {
/**
* Check specific role @see {@link Role}.
*
* @param role to check
* @return true if the role exists otherwise false
*/
@ -47,6 +50,7 @@ public abstract class Customer {
/**
* Remove specific role @see {@link Role}.
*
* @param role to remove
* @return true if the operation has been successful otherwise false
*/
@ -54,6 +58,7 @@ public abstract class Customer {
/**
* Get specific instance associated with this role @see {@link Role}.
*
* @param role to get
* @param expectedRole instance class expected to get
* @return optional with value if the instance exists and corresponds expected class
@ -67,14 +72,13 @@ public abstract class Customer {
/**
* Create {@link Customer} with given roles.
*
* @param role roles
* @return Customer
*/
public static Customer newCustomer(Role... role) {
Customer customer = newCustomer();
for (Role r : role) {
customer.addRole(r);
}
var customer = newCustomer();
Arrays.stream(role).forEach(customer::addRole);
return customer;
}

2
role-object/src/main/java/com/iluwatar/roleobject/CustomerCore.java
View File

@ -73,7 +73,7 @@ public class CustomerCore extends Customer {
@Override
public String toString() {
String roles = Arrays.toString(this.roles.keySet().toArray());
var roles = Arrays.toString(this.roles.keySet().toArray());
return "Customer{roles=" + roles + "}";
}
}

3
role-object/src/main/java/com/iluwatar/roleobject/Role.java
View File

@ -24,7 +24,6 @@
package com.iluwatar.roleobject;
import java.util.Optional;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
@ -48,7 +47,7 @@ public enum Role {
*/
@SuppressWarnings("unchecked")
public <T extends CustomerRole> Optional<T> instance() {
Class<? extends CustomerRole> typeCst = this.typeCst;
var typeCst = this.typeCst;
try {
return (Optional<T>) Optional.of(typeCst.newInstance());
} catch (InstantiationException | IllegalAccessException e) {

8
role-object/src/test/java/com/iluwatar/roleobject/BorrowerRoleTest.java
View File

@ -25,16 +25,12 @@ package com.iluwatar.roleobject;
import org.junit.Assert;
import org.junit.Test;
import static org.junit.Assert.*;
public class BorrowerRoleTest {
@Test
public void borrowTest() {
BorrowerRole borrowerRole = new BorrowerRole();
var borrowerRole = new BorrowerRole();
borrowerRole.setName("test");
String res = "Borrower test wants to get some money.";
Assert.assertEquals(borrowerRole.borrow(),res);
Assert.assertEquals(borrowerRole.borrow(), "Borrower test wants to get some money.");
}
}

46
role-object/src/test/java/com/iluwatar/roleobject/CustomerCoreTest.java
View File

@ -22,71 +22,61 @@
*/
package com.iluwatar.roleobject;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;
import org.junit.Test;
import java.util.Optional;
import static org.junit.Assert.*;
public class CustomerCoreTest {
@Test
public void addRole() {
CustomerCore core = new CustomerCore();
boolean add = core.addRole(Role.Borrower);
assertTrue(add);
var core = new CustomerCore();
assertTrue(core.addRole(Role.Borrower));
}
@Test
public void hasRole() {
CustomerCore core = new CustomerCore();
var core = new CustomerCore();
core.addRole(Role.Borrower);
boolean has = core.hasRole(Role.Borrower);
assertTrue(has);
boolean notHas = core.hasRole(Role.Investor);
assertFalse(notHas);
assertTrue(core.hasRole(Role.Borrower));
assertFalse(core.hasRole(Role.Investor));
}
@Test
public void remRole() {
CustomerCore core = new CustomerCore();
var core = new CustomerCore();
core.addRole(Role.Borrower);
Optional<BorrowerRole> bRole = core.getRole(Role.Borrower, BorrowerRole.class);
var bRole = core.getRole(Role.Borrower, BorrowerRole.class);
assertTrue(bRole.isPresent());
boolean res = core.remRole(Role.Borrower);
assertTrue(res);
assertTrue(core.remRole(Role.Borrower));
Optional<BorrowerRole> empt = core.getRole(Role.Borrower, BorrowerRole.class);
var empt = core.getRole(Role.Borrower, BorrowerRole.class);
assertFalse(empt.isPresent());
}
@Test
public void getRole() {
CustomerCore core = new CustomerCore();
var core = new CustomerCore();
core.addRole(Role.Borrower);
Optional<BorrowerRole> bRole = core.getRole(Role.Borrower, BorrowerRole.class);
var bRole = core.getRole(Role.Borrower, BorrowerRole.class);
assertTrue(bRole.isPresent());
Optional<InvestorRole> nonRole = core.getRole(Role.Borrower, InvestorRole.class);
var nonRole = core.getRole(Role.Borrower, InvestorRole.class);
assertFalse(nonRole.isPresent());
Optional<InvestorRole> invRole = core.getRole(Role.Investor, InvestorRole.class);
var invRole = core.getRole(Role.Investor, InvestorRole.class);
assertFalse(invRole.isPresent());
}
@Test
public void toStringTest() {
CustomerCore core = new CustomerCore();
var core = new CustomerCore();
core.addRole(Role.Borrower);
assertEquals(core.toString(), "Customer{roles=[Borrower]}");

5
role-object/src/test/java/com/iluwatar/roleobject/InvestorRoleTest.java
View File

@ -29,10 +29,9 @@ public class InvestorRoleTest {
@Test
public void investTest() {
InvestorRole investorRole = new InvestorRole();
var investorRole = new InvestorRole();
investorRole.setName("test");
investorRole.setAmountToInvest(10);
String res = "Investor test has invested 10 dollars";
Assert.assertEquals(investorRole.invest(), res);
Assert.assertEquals(investorRole.invest(), "Investor test has invested 10 dollars");
}
}

6
role-object/src/test/java/com/iluwatar/roleobject/RoleTest.java
View File

@ -25,15 +25,11 @@ package com.iluwatar.roleobject;
import org.junit.Assert;
import org.junit.Test;
import java.util.Optional;
import static org.junit.Assert.*;
public class RoleTest {
@Test
public void instanceTest() {
Optional<CustomerRole> instance = Role.Borrower.instance();
var instance = Role.Borrower.instance();
Assert.assertTrue(instance.isPresent());
Assert.assertEquals(instance.get().getClass(), BorrowerRole.class);
}