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Merge pull request #281 from ankurkaushal/master

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Reformat according to google style guide
This commit is contained in:
Ilkka Seppälä
2015-11-02 21:39:17 +02:00
parent 7e4f04602e 306b1f3d31
commit fe63c9cec4
438 changed files with 8257 additions and 8382 deletions
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64
poison-pill/src/main/java/com/iluwatar/poison/pill/App.java
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@ -1,43 +1,45 @@
package com.iluwatar.poison.pill;
/**
* One of the possible approaches to terminate Producer-Consumer pattern is using the Poison Pill idiom.
* If you use Poison Pill as the termination signal then Producer is responsible to notify Consumer that
* the exchange is over and reject any further messages. The Consumer receiving Poison Pill will stop
* reading messages from the queue. You must also ensure that the Poison Pill will be the last message
* that will be read from the queue (if you have prioritized queue then this can be tricky).
* One of the possible approaches to terminate Producer-Consumer pattern is using the Poison Pill
* idiom. If you use Poison Pill as the termination signal then Producer is responsible to notify
* Consumer that the exchange is over and reject any further messages. The Consumer receiving Poison
* Pill will stop reading messages from the queue. You must also ensure that the Poison Pill will be
* the last message that will be read from the queue (if you have prioritized queue then this can be
* tricky).
* <p>
* In simple cases the Poison Pill can be just a null-reference, but holding a unique separate shared
* object-marker (with name "Poison" or "Poison Pill") is more clear and self describing.
* In simple cases the Poison Pill can be just a null-reference, but holding a unique separate
* shared object-marker (with name "Poison" or "Poison Pill") is more clear and self describing.
*
*/
public class App {
/**
* Program entry point
* @param args command line args
*/
public static void main(String[] args) {
MessageQueue queue = new SimpleMessageQueue(10000);
/**
* Program entry point
*
* @param args command line args
*/
public static void main(String[] args) {
MessageQueue queue = new SimpleMessageQueue(10000);
final Producer producer = new Producer("PRODUCER_1", queue);
final Consumer consumer = new Consumer("CONSUMER_1", queue);
final Producer producer = new Producer("PRODUCER_1", queue);
final Consumer consumer = new Consumer("CONSUMER_1", queue);
new Thread() {
@Override
public void run() {
consumer.consume();
}
}.start();
new Thread() {
@Override
public void run() {
consumer.consume();
}
}.start();
new Thread() {
@Override
public void run() {
producer.send("hand shake");
producer.send("some very important information");
producer.send("bye!");
producer.stop();
}
}.start();
}
new Thread() {
@Override
public void run() {
producer.send("hand shake");
producer.send("some very important information");
producer.send("bye!");
producer.stop();
}
}.start();
}
}

51
poison-pill/src/main/java/com/iluwatar/poison/pill/Consumer.java
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@ -7,32 +7,33 @@ import com.iluwatar.poison.pill.Message.Headers;
*/
public class Consumer {
private final MQSubscribePoint queue;
private final String name;
private final MQSubscribePoint queue;
private final String name;
public Consumer(String name, MQSubscribePoint queue) {
this.name = name;
this.queue = queue;
}
public Consumer(String name, MQSubscribePoint queue) {
this.name = name;
this.queue = queue;
}
public void consume() {
while (true) {
Message msg;
try {
msg = queue.take();
if (msg == Message.POISON_PILL) {
System.out.println(String.format("Consumer %s receive request to terminate.", name));
break;
}
} catch (InterruptedException e) {
// allow thread to exit
System.err.println(e);
return;
}
public void consume() {
while (true) {
Message msg;
try {
msg = queue.take();
if (msg == Message.POISON_PILL) {
System.out.println(String.format("Consumer %s receive request to terminate.", name));
break;
}
} catch (InterruptedException e) {
// allow thread to exit
System.err.println(e);
return;
}
String sender = msg.getHeader(Headers.SENDER);
String body = msg.getBody();
System.out.println(String.format("Message [%s] from [%s] received by [%s]", body, sender, name));
}
}
String sender = msg.getHeader(Headers.SENDER);
String body = msg.getBody();
System.out.println(String.format("Message [%s] from [%s] received by [%s]", body, sender,
name));
}
}
}

2
poison-pill/src/main/java/com/iluwatar/poison/pill/MQPublishPoint.java
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@ -5,5 +5,5 @@ package com.iluwatar.poison.pill;
*/
public interface MQPublishPoint {
public void put(Message msg) throws InterruptedException;
public void put(Message msg) throws InterruptedException;
}

2
poison-pill/src/main/java/com/iluwatar/poison/pill/MQSubscribePoint.java
View File

@ -5,5 +5,5 @@ package com.iluwatar.poison.pill;
*/
public interface MQSubscribePoint {
public Message take() throws InterruptedException;
public Message take() throws InterruptedException;
}

74
poison-pill/src/main/java/com/iluwatar/poison/pill/Message.java
View File

@ -3,51 +3,55 @@ package com.iluwatar.poison.pill;
import java.util.Map;
/**
* Interface that implements the Message pattern and represents an inbound or outbound
* message as part of an {@link Producer}-{@link Consumer} exchange.
* Interface that implements the Message pattern and represents an inbound or outbound message as
* part of an {@link Producer}-{@link Consumer} exchange.
*/
public interface Message {
public static final Message POISON_PILL = new Message() {
public static final Message POISON_PILL = new Message() {
@Override
public void addHeader(Headers header, String value) {
throw poison();
}
@Override
public void addHeader(Headers header, String value) {
throw poison();
}
@Override
public String getHeader(Headers header) {
throw poison();
}
@Override
public String getHeader(Headers header) {
throw poison();
}
@Override
public Map<Headers, String> getHeaders() {
throw poison();
}
@Override
public Map<Headers, String> getHeaders() {
throw poison();
}
@Override
public void setBody(String body) {
throw poison();
}
@Override
public void setBody(String body) {
throw poison();
}
@Override
public String getBody() {
throw poison();
}
@Override
public String getBody() {
throw poison();
}
private RuntimeException poison() {
return new UnsupportedOperationException("Poison");
}
private RuntimeException poison() {
return new UnsupportedOperationException("Poison");
}
};
};
public enum Headers {
DATE, SENDER
}
public enum Headers {
DATE, SENDER
}
public void addHeader(Headers header, String value);
public String getHeader(Headers header);
public Map<Headers, String> getHeaders();
public void setBody(String body);
public String getBody();
public void addHeader(Headers header, String value);
public String getHeader(Headers header);
public Map<Headers, String> getHeaders();
public void setBody(String body);
public String getBody();
}

68
poison-pill/src/main/java/com/iluwatar/poison/pill/Producer.java
View File

@ -5,44 +5,46 @@ import java.util.Date;
import com.iluwatar.poison.pill.Message.Headers;
/**
* Class responsible for producing unit of work that can be expressed as message and submitted to queue
* Class responsible for producing unit of work that can be expressed as message and submitted to
* queue
*/
public class Producer {
private final MQPublishPoint queue;
private final String name;
private boolean isStopped;
private final MQPublishPoint queue;
private final String name;
private boolean isStopped;
public Producer(String name, MQPublishPoint queue) {
this.name = name;
this.queue = queue;
this.isStopped = false;
}
public Producer(String name, MQPublishPoint queue) {
this.name = name;
this.queue = queue;
this.isStopped = false;
}
public void send(String body) {
if (isStopped) {
throw new IllegalStateException(String.format("Producer %s was stopped and fail to deliver requested message [%s].", body, name));
}
Message msg = new SimpleMessage();
msg.addHeader(Headers.DATE, new Date().toString());
msg.addHeader(Headers.SENDER, name);
msg.setBody(body);
public void send(String body) {
if (isStopped) {
throw new IllegalStateException(String.format(
"Producer %s was stopped and fail to deliver requested message [%s].", body, name));
}
Message msg = new SimpleMessage();
msg.addHeader(Headers.DATE, new Date().toString());
msg.addHeader(Headers.SENDER, name);
msg.setBody(body);
try {
queue.put(msg);
} catch (InterruptedException e) {
// allow thread to exit
System.err.println(e);
}
}
try {
queue.put(msg);
} catch (InterruptedException e) {
// allow thread to exit
System.err.println(e);
}
}
public void stop() {
isStopped = true;
try {
queue.put(Message.POISON_PILL);
} catch (InterruptedException e) {
// allow thread to exit
System.err.println(e);
}
}
public void stop() {
isStopped = true;
try {
queue.put(Message.POISON_PILL);
} catch (InterruptedException e) {
// allow thread to exit
System.err.println(e);
}
}
}

44
poison-pill/src/main/java/com/iluwatar/poison/pill/SimpleMessage.java
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@ -9,31 +9,31 @@ import java.util.Map;
*/
public class SimpleMessage implements Message {
private Map<Headers, String> headers = new HashMap<>();
private String body;
private Map<Headers, String> headers = new HashMap<>();
private String body;
@Override
public void addHeader(Headers header, String value) {
headers.put(header, value);
}
@Override
public void addHeader(Headers header, String value) {
headers.put(header, value);
}
@Override
public String getHeader(Headers header) {
return headers.get(header);
}
@Override
public String getHeader(Headers header) {
return headers.get(header);
}
@Override
public Map<Headers, String> getHeaders() {
return Collections.unmodifiableMap(headers);
}
@Override
public Map<Headers, String> getHeaders() {
return Collections.unmodifiableMap(headers);
}
@Override
public void setBody(String body) {
this.body = body;
}
@Override
public void setBody(String body) {
this.body = body;
}
@Override
public String getBody() {
return body;
}
@Override
public String getBody() {
return body;
}
}

25
poison-pill/src/main/java/com/iluwatar/poison/pill/SimpleMessageQueue.java
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@ -8,20 +8,19 @@ import java.util.concurrent.BlockingQueue;
*/
public class SimpleMessageQueue implements MessageQueue {
private final BlockingQueue<Message> queue;
private final BlockingQueue<Message> queue;
public SimpleMessageQueue(int bound) {
queue = new ArrayBlockingQueue<Message>(bound);
}
public SimpleMessageQueue(int bound) {
queue = new ArrayBlockingQueue<Message>(bound);
}
@Override
public void put(Message msg) throws InterruptedException {
queue.put(msg);
}
@Override
public Message take() throws InterruptedException {
return queue.take();
}
@Override
public void put(Message msg) throws InterruptedException {
queue.put(msg);
}
@Override
public Message take() throws InterruptedException {
return queue.take();
}
}

10
poison-pill/src/test/java/com/iluwatar/poison/pill/AppTest.java
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@ -11,9 +11,9 @@ import com.iluwatar.poison.pill.App;
*/
public class AppTest {
@Test
public void test() {
String[] args = {};
App.main(args);
}
@Test
public void test() {
String[] args = {};
App.main(args);
}
}