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Reformat rest of the design patterns - Issue #224

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This commit is contained in:
Ankur Kaushal
2015-11-01 21:29:13 -05:00
parent 449340bd2b
commit 306b1f3d31
337 changed files with 6744 additions and 6851 deletions
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113
thread-pool/src/main/java/com/iluwatar/threadpool/App.java
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@ -7,64 +7,65 @@ import java.util.concurrent.Executors;
/**
*
* Thread Pool pattern is where a number of threads are created to perform a number of tasks,
* which are usually organized in a queue. The results from the tasks being executed might
* also be placed in a queue, or the tasks might return no result. Typically, there are many
* more tasks than threads. As soon as a thread completes its task, it will request the next
* task from the queue until all tasks have been completed. The thread can then terminate, or
* sleep until there are new tasks available.
* <p>
* In this example we create a list of tasks presenting work to be done. Each task is then
* wrapped into a {@link Worker} object that implements {@link Runnable}. We create an
* {@link ExecutorService} with fixed number of threads (Thread Pool) and use them to execute
* the {@link Worker}s.
* Thread Pool pattern is where a number of threads are created to perform a number of tasks, which
* are usually organized in a queue. The results from the tasks being executed might also be placed
* in a queue, or the tasks might return no result. Typically, there are many more tasks than
* threads. As soon as a thread completes its task, it will request the next task from the queue
* until all tasks have been completed. The thread can then terminate, or sleep until there are new
* tasks available.
* <p>
* In this example we create a list of tasks presenting work to be done. Each task is then wrapped
* into a {@link Worker} object that implements {@link Runnable}. We create an
* {@link ExecutorService} with fixed number of threads (Thread Pool) and use them to execute the
* {@link Worker}s.
*
*/
public class App {
/**
* Program entry point
* @param args command line args
*/
public static void main( String[] args ) {
System.out.println("Program started");
// Create a list of tasks to be executed
List<Task> tasks = new ArrayList<>();
tasks.add(new PotatoPeelingTask(3));
tasks.add(new PotatoPeelingTask(6));
tasks.add(new CoffeeMakingTask(2));
tasks.add(new CoffeeMakingTask(6));
tasks.add(new PotatoPeelingTask(4));
tasks.add(new CoffeeMakingTask(2));
tasks.add(new PotatoPeelingTask(4));
tasks.add(new CoffeeMakingTask(9));
tasks.add(new PotatoPeelingTask(3));
tasks.add(new CoffeeMakingTask(2));
tasks.add(new PotatoPeelingTask(4));
tasks.add(new CoffeeMakingTask(2));
tasks.add(new CoffeeMakingTask(7));
tasks.add(new PotatoPeelingTask(4));
tasks.add(new PotatoPeelingTask(5));
// Creates a thread pool that reuses a fixed number of threads operating off a shared
// unbounded queue. At any point, at most nThreads threads will be active processing
// tasks. If additional tasks are submitted when all threads are active, they will wait
// in the queue until a thread is available.
ExecutorService executor = Executors.newFixedThreadPool(3);
// Allocate new worker for each task
// The worker is executed when a thread becomes
// available in the thread pool
for (int i=0; i<tasks.size(); i++) {
Runnable worker = new Worker(tasks.get(i));
executor.execute(worker);
}
// All tasks were executed, now shutdown
executor.shutdown();
while (!executor.isTerminated()) {
}
System.out.println("Program finished");
/**
* Program entry point
*
* @param args command line args
*/
public static void main(String[] args) {
System.out.println("Program started");
// Create a list of tasks to be executed
List<Task> tasks = new ArrayList<>();
tasks.add(new PotatoPeelingTask(3));
tasks.add(new PotatoPeelingTask(6));
tasks.add(new CoffeeMakingTask(2));
tasks.add(new CoffeeMakingTask(6));
tasks.add(new PotatoPeelingTask(4));
tasks.add(new CoffeeMakingTask(2));
tasks.add(new PotatoPeelingTask(4));
tasks.add(new CoffeeMakingTask(9));
tasks.add(new PotatoPeelingTask(3));
tasks.add(new CoffeeMakingTask(2));
tasks.add(new PotatoPeelingTask(4));
tasks.add(new CoffeeMakingTask(2));
tasks.add(new CoffeeMakingTask(7));
tasks.add(new PotatoPeelingTask(4));
tasks.add(new PotatoPeelingTask(5));
// Creates a thread pool that reuses a fixed number of threads operating off a shared
// unbounded queue. At any point, at most nThreads threads will be active processing
// tasks. If additional tasks are submitted when all threads are active, they will wait
// in the queue until a thread is available.
ExecutorService executor = Executors.newFixedThreadPool(3);
// Allocate new worker for each task
// The worker is executed when a thread becomes
// available in the thread pool
for (int i = 0; i < tasks.size(); i++) {
Runnable worker = new Worker(tasks.get(i));
executor.execute(worker);
}
// All tasks were executed, now shutdown
executor.shutdown();
while (!executor.isTerminated()) {
}
System.out.println("Program finished");
}
}

18
thread-pool/src/main/java/com/iluwatar/threadpool/CoffeeMakingTask.java
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@ -7,14 +7,14 @@ package com.iluwatar.threadpool;
*/
public class CoffeeMakingTask extends Task {
private static final int TIME_PER_CUP = 300;
public CoffeeMakingTask(int numCups) {
super(numCups * TIME_PER_CUP);
}
private static final int TIME_PER_CUP = 300;
@Override
public String toString() {
return String.format("%s %s", this.getClass().getSimpleName(), super.toString());
}
public CoffeeMakingTask(int numCups) {
super(numCups * TIME_PER_CUP);
}
@Override
public String toString() {
return String.format("%s %s", this.getClass().getSimpleName(), super.toString());
}
}

20
thread-pool/src/main/java/com/iluwatar/threadpool/PotatoPeelingTask.java
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@ -7,14 +7,14 @@ package com.iluwatar.threadpool;
*/
public class PotatoPeelingTask extends Task {
private static final int TIME_PER_POTATO = 500;
public PotatoPeelingTask(int numPotatoes) {
super(numPotatoes * TIME_PER_POTATO);
}
@Override
public String toString() {
return String.format("%s %s", this.getClass().getSimpleName(), super.toString());
}
private static final int TIME_PER_POTATO = 500;
public PotatoPeelingTask(int numPotatoes) {
super(numPotatoes * TIME_PER_POTATO);
}
@Override
public String toString() {
return String.format("%s %s", this.getClass().getSimpleName(), super.toString());
}
}

44
thread-pool/src/main/java/com/iluwatar/threadpool/Task.java
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@ -7,26 +7,26 @@ package com.iluwatar.threadpool;
*/
public abstract class Task {
private static int nextId = 1;
private final int id;
private final int timeMs;
public Task(final int timeMs) {
this.id = nextId++;
this.timeMs = timeMs;
}
public int getId() {
return id;
}
public int getTimeMs() {
return timeMs;
}
@Override
public String toString() {
return String.format("id=%d timeMs=%d", id, timeMs);
}
private static int nextId = 1;
private final int id;
private final int timeMs;
public Task(final int timeMs) {
this.id = nextId++;
this.timeMs = timeMs;
}
public int getId() {
return id;
}
public int getTimeMs() {
return timeMs;
}
@Override
public String toString() {
return String.format("id=%d timeMs=%d", id, timeMs);
}
}

31
thread-pool/src/main/java/com/iluwatar/threadpool/Worker.java
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@ -6,20 +6,21 @@ package com.iluwatar.threadpool;
*
*/
public class Worker implements Runnable {
private final Task task;
public Worker(final Task task) {
this.task = task;
}
@Override
public void run() {
System.out.println(String.format("%s processing %s", Thread.currentThread().getName(), task.toString()));
try {
Thread.sleep(task.getTimeMs());
} catch (InterruptedException e) {
e.printStackTrace();
}
}
private final Task task;
public Worker(final Task task) {
this.task = task;
}
@Override
public void run() {
System.out.println(String.format("%s processing %s", Thread.currentThread().getName(),
task.toString()));
try {
Thread.sleep(task.getTimeMs());
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}

13
thread-pool/src/test/java/com/iluwatar/threadpool/AppTest.java
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@ -6,14 +6,15 @@ import com.iluwatar.threadpool.App;
/**
* Application test
*
* @author ilkka
*
*/
public class AppTest {
@Test
public void test() {
String[] args = {};
App.main(args);
}
@Test
public void test() {
String[] args = {};
App.main(args);
}
}