Added interface BlockingDeque, and implementation for ExecutorCompletionService and LinkedBlockingQueue.

I had to implement a blocking queue for ExecutorCompletionService.  LinkedBlockingQueue could be very easily extended right now to implement the java 7 LinkedBlockingDeque.  Right now LinkedBlockingQueue just synchronizes and depends on LinkedList implementation.  But I wrote a very complete unit test suite so we if we want to put a more concurrent design here, we have a complete test suite to verify against.# Please enter the commit message for your changes. Lines starting
This commit is contained in:
Mike Jensen 2014-03-10 19:06:37 -06:00
parent ed89e0c67d
commit 68fca60d21
5 changed files with 890 additions and 0 deletions

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package java.util.concurrent;
import java.util.Deque;
public interface BlockingDeque<T> extends Deque<T>, BlockingQueue<T> {
public T takeFirst() throws InterruptedException;
public T takeLast() throws InterruptedException;
public T pollFirst(long timeout, TimeUnit unit) throws InterruptedException;
public T pollLast(long timeout, TimeUnit unit) throws InterruptedException;
}

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package java.util.concurrent;
public class ExecutorCompletionService<T> implements CompletionService<T> {
private final Executor executor;
private final BlockingQueue<Future<T>> completionQueue;
public ExecutorCompletionService(Executor executor) {
this(executor, new LinkedBlockingQueue<Future<T>>());
}
public ExecutorCompletionService(Executor executor, BlockingQueue<Future<T>> completionQueue) {
this.executor = executor;
this.completionQueue = completionQueue;
}
@Override
public Future<T> submit(Callable<T> task) {
ECSFuture f = new ECSFuture(task);
executor.execute(f);
return f;
}
@Override
public Future<T> submit(Runnable task, T result) {
ECSFuture f = new ECSFuture(task, result);
executor.execute(f);
return f;
}
@Override
public Future<T> take() throws InterruptedException {
return completionQueue.take();
}
@Override
public Future<T> poll() {
return completionQueue.poll();
}
@Override
public Future<T> poll(long timeout, TimeUnit unit) throws InterruptedException {
return completionQueue.poll(timeout, unit);
}
private class ECSFuture extends FutureTask<T> implements Future<T> {
private ECSFuture(Runnable r, T result) {
super(r, result);
}
private ECSFuture(Callable<T> callable) {
super(callable);
}
@Override
protected void done() {
completionQueue.add(this);
}
}
}

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package java.util.concurrent;
import java.util.Collection;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.NoSuchElementException;
public class LinkedBlockingQueue<T> implements BlockingQueue<T> {
private final Object collectionLock;
private final LinkedList<T> storage;
private final int capacity;
public LinkedBlockingQueue() {
this(Integer.MAX_VALUE);
}
public LinkedBlockingQueue(int capacity) {
collectionLock = new Object();
this.capacity = capacity;
storage = new LinkedList<T>();
}
// should be synchronized on collectionLock before calling
private void handleRemove() {
collectionLock.notifyAll();
}
// should be synchronized on collectionLock before calling
private void handleAdd() {
collectionLock.notifyAll();
}
// should be synchronized on collectionLock before calling
private void blockTillNotFull() throws InterruptedException {
blockTillNotFull(Long.MAX_VALUE);
}
// should be synchronized on collectionLock before calling
private void blockTillNotFull(long maxWaitInMillis) throws InterruptedException {
if (capacity > storage.size()) {
return;
}
long startTime = 0;
if (maxWaitInMillis != Long.MAX_VALUE) {
startTime = System.currentTimeMillis();
}
long remainingWait = maxWaitInMillis;
while (remainingWait > 0) {
collectionLock.wait(remainingWait);
if (capacity > storage.size()) {
return;
} else if (maxWaitInMillis != Long.MAX_VALUE) {
remainingWait = maxWaitInMillis - (System.currentTimeMillis() - startTime);
}
}
}
// should be synchronized on collectionLock before calling
private void blockTillNotEmpty() throws InterruptedException {
blockTillNotEmpty(Long.MAX_VALUE);
}
// should be synchronized on collectionLock before calling
private void blockTillNotEmpty(long maxWaitInMillis) throws InterruptedException {
if (! storage.isEmpty()) {
return;
}
long startTime = 0;
if (maxWaitInMillis != Long.MAX_VALUE) {
startTime = System.currentTimeMillis();
}
long remainingWait = maxWaitInMillis;
while (remainingWait > 0) {
collectionLock.wait(remainingWait);
if (! storage.isEmpty()) {
return;
} else if (maxWaitInMillis != Long.MAX_VALUE) {
remainingWait = maxWaitInMillis - (System.currentTimeMillis() - startTime);
}
}
}
@Override
public boolean add(T element) {
if (! offer(element)) {
throw new IllegalStateException("At capacity");
}
return true;
}
@Override
public boolean offer(T element) {
synchronized (collectionLock) {
if (capacity > storage.size()) {
storage.addLast(element);
handleAdd();
return true;
} else {
return false;
}
}
}
@Override
public boolean offer(T e, long timeout, TimeUnit unit) throws InterruptedException {
long timeoutInMillis = unit.toMillis(timeout);
synchronized (collectionLock) {
// block till we can add or have reached timeout
blockTillNotFull(timeoutInMillis);
return offer(e);
}
}
@Override
public void put(T e) throws InterruptedException {
synchronized (collectionLock) {
// block till we have space
blockTillNotFull();
storage.add(e);
handleAdd();
}
}
@Override
public boolean addAll(Collection<? extends T> c) {
synchronized (collectionLock) {
if (storage.size() + c.size() > capacity) {
throw new IllegalStateException("Not enough space");
}
if (c.isEmpty()) {
return false;
} else {
storage.addAll(c);
return true;
}
}
}
@Override
public T peek() {
synchronized (collectionLock) {
if (storage.isEmpty()) {
return null;
} else {
return storage.getFirst();
}
}
}
@Override
public T element() {
T result = peek();
if (result == null) {
throw new NoSuchElementException();
}
return result;
}
// should be synchronized on collectionLock before calling
private T removeFirst() {
T result = storage.removeFirst();
handleRemove();
return result;
}
@Override
public T poll() {
synchronized (collectionLock) {
if (storage.isEmpty()) {
return null;
} else {
return removeFirst();
}
}
}
@Override
public T poll(long timeout, TimeUnit unit) throws InterruptedException {
long timeoutInMillis = unit.toMillis(timeout);
synchronized (collectionLock) {
// block till we available or timeout
blockTillNotEmpty(timeoutInMillis);
return poll();
}
}
@Override
public T take() throws InterruptedException {
synchronized (collectionLock) {
// block till we available
blockTillNotEmpty();
return removeFirst();
}
}
@Override
public T remove() {
T result = poll();
if (result == null) {
throw new NoSuchElementException();
}
return result;
}
@Override
public int drainTo(Collection<? super T> c) {
return drainTo(c, Integer.MAX_VALUE);
}
@Override
public int drainTo(Collection<? super T> c, int maxElements) {
int remainingElements = maxElements;
synchronized (collectionLock) {
while (remainingElements > 0 && ! storage.isEmpty()) {
c.add(storage.removeFirst());
remainingElements--;
}
if (remainingElements != maxElements) {
handleRemove();
}
return maxElements - remainingElements;
}
}
@Override
public int remainingCapacity() {
synchronized (collectionLock) {
return capacity - storage.size();
}
}
@Override
public int size() {
synchronized (collectionLock) {
return storage.size();
}
}
@Override
public boolean isEmpty() {
return size() == 0;
}
@Override
public boolean contains(Object element) {
synchronized (collectionLock) {
return storage.contains(element);
}
}
@Override
public boolean containsAll(Collection<?> c) {
synchronized (collectionLock) {
return storage.containsAll(c);
}
}
@Override
public boolean remove(Object element) {
synchronized (collectionLock) {
if (storage.remove(element)) {
handleRemove();
return true;
} else {
return false;
}
}
}
@Override
public boolean removeAll(Collection<?> c) {
synchronized (collectionLock) {
if (storage.removeAll(c)) {
handleRemove();
return true;
} else {
return false;
}
}
}
@Override
public void clear() {
synchronized (collectionLock) {
storage.clear();
}
}
@Override
public Object[] toArray() {
synchronized (collectionLock) {
return storage.toArray();
}
}
@Override
public <S> S[] toArray(S[] array) {
synchronized (collectionLock) {
return storage.toArray(array);
}
}
@Override
public Iterator<T> iterator() {
throw new UnsupportedOperationException("Not implemented yet");
}
}

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import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executor;
import java.util.concurrent.ExecutorCompletionService;
import java.util.concurrent.TimeUnit;
public class CompleteionServiceTest {
public static void main(String args[]) throws InterruptedException, ExecutionException {
Executor dumbExecutor = new Executor() {
@Override
public void execute(Runnable task) {
new Thread(task).start();
}
};
pollNoResultTest(dumbExecutor);
pollTimeoutNoResultTest(dumbExecutor);
takeTest(dumbExecutor);
}
private static void pollNoResultTest(Executor executor) {
ExecutorCompletionService<Object> ecs = new ExecutorCompletionService<Object>(executor);
if (ecs.poll() != null) {
throw new RuntimeException();
}
}
private static void pollTimeoutNoResultTest(Executor executor) throws InterruptedException {
long delayTime = 0;
ExecutorCompletionService<Object> ecs = new ExecutorCompletionService<Object>(executor);
long startTime = System.currentTimeMillis();
if (ecs.poll(delayTime, TimeUnit.MILLISECONDS) != null) {
throw new RuntimeException();
}
if (System.currentTimeMillis() - startTime < delayTime) {
throw new RuntimeException();
}
}
private static void takeTest(Executor executor) throws InterruptedException, ExecutionException {
ExecutorCompletionService<Object> ecs = new ExecutorCompletionService<Object>(executor);
final Object result = new Object();
ecs.submit(new Callable<Object>() {
@Override
public Object call() throws Exception {
return result;
}
});
if (ecs.take().get() != result) {
throw new RuntimeException();
}
}
}

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import java.util.LinkedList;
import java.util.NoSuchElementException;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.TimeUnit;
public class LinkedBlockingQueueTest {
private static final int DELAY_TILL_ACTION = 10;
public static void main(String[] args) throws InterruptedException {
remainingCapacityTest();
sizeTest();
isEmptyTest();
addTest();
addCapacityFail();
offerTest();
offerWithTimeoutTest();
offerTimeoutTest();
putTest();
addAllTest();
addAllFail();
elementTest();
elementFail();
pollEmptyTest();
pollTest();
pollTimeoutTest();
takeTest();
removeEmptyTest();
removeTest();
drainToTest();
drainToLimitTest();
containsTest();
containsAllTest();
removeObjectTest();
removeAllTest();
clearTest();
toArrayTest();
}
private static void remainingCapacityTest() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>(2);
if (lbq.remainingCapacity() != 2) {
throw new RuntimeException();
}
lbq.add(new Object());
if (lbq.remainingCapacity() != 1) {
throw new RuntimeException();
}
}
private static void sizeTest() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
if (lbq.size() != 0) {
throw new RuntimeException();
}
lbq.add(new Object());
if (lbq.size() != 1) {
throw new RuntimeException();
}
}
private static void isEmptyTest() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
if (! lbq.isEmpty()) {
throw new RuntimeException();
}
lbq.add(new Object());
if (lbq.isEmpty()) {
throw new RuntimeException();
}
}
private static void addTest() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
Object testObject = new Object();
lbq.add(testObject);
if (lbq.size() != 1) {
throw new RuntimeException();
} else if (lbq.peek() != testObject) {
throw new RuntimeException();
}
}
private static void addCapacityFail() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>(1);
Object testObject = new Object();
lbq.add(testObject);
try {
lbq.add(new Object());
throw new RuntimeException("Exception should have thrown");
} catch (IllegalStateException e) {
// expected
}
if (lbq.size() != 1) {
throw new RuntimeException();
} else if (lbq.peek() != testObject) {
throw new RuntimeException();
}
}
private static void offerTest() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>(1);
Object testObject = new Object();
if (! lbq.offer(testObject)) {
throw new RuntimeException();
}
if (lbq.offer(new Object())) {
throw new RuntimeException();
}
if (lbq.size() != 1) {
throw new RuntimeException();
} else if (lbq.peek() != testObject) {
throw new RuntimeException();
}
}
private static void offerWithTimeoutTest() throws InterruptedException {
final LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>(1);
lbq.add(new Object());
new Thread(new Runnable() {
@Override
public void run() {
try {
// sleep to make sure offer call starts first
Thread.sleep(DELAY_TILL_ACTION);
lbq.take();
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
}
}
}).start();
// should accept once thread starts
if (! lbq.offer(new Object(), 10, TimeUnit.SECONDS)) {
throw new RuntimeException();
}
}
private static void offerTimeoutTest() throws InterruptedException {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>(1);
lbq.add(new Object());
if (lbq.offer(new Object(), 10, TimeUnit.MILLISECONDS)) {
throw new RuntimeException();
}
}
private static void putTest() throws InterruptedException {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
Object testObject = new Object();
lbq.put(testObject);
if (lbq.size() != 1) {
throw new RuntimeException();
} else if (lbq.peek() != testObject) {
throw new RuntimeException();
}
}
private static void addAllTest() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
LinkedList<Object> toAdd = new LinkedList<Object>();
toAdd.add(new Object());
toAdd.add(new Object());
lbq.addAll(toAdd);
if (lbq.size() != toAdd.size()) {
throw new RuntimeException();
}
while (! lbq.isEmpty()) {
if (lbq.remove() != toAdd.remove()) {
throw new RuntimeException();
}
}
}
private static void addAllFail() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>(1);
LinkedList<Object> toAdd = new LinkedList<Object>();
toAdd.add(new Object());
toAdd.add(new Object());
try {
lbq.addAll(toAdd);
throw new RuntimeException("Exception should have thrown");
} catch (IllegalStateException e) {
// expected
}
}
private static void elementTest() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
Object testObject = new Object();
lbq.add(testObject);
if (lbq.element() != testObject) {
throw new RuntimeException();
}
}
private static void elementFail() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
try {
lbq.element();
throw new RuntimeException("Exception should have thrown");
} catch (NoSuchElementException e) {
// expected
}
}
private static void pollEmptyTest() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
if (lbq.poll() != null) {
throw new RuntimeException();
}
}
private static void pollTest() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
Object testObject = new Object();
lbq.add(testObject);
if (lbq.poll() != testObject) {
throw new RuntimeException();
}
}
private static void pollTimeoutTest() throws InterruptedException {
final LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
final Object testObject = new Object();
new Thread(new Runnable() {
@Override
public void run() {
try {
Thread.sleep(DELAY_TILL_ACTION);
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
}
lbq.add(testObject);
}
}).start();
if (lbq.poll(DELAY_TILL_ACTION * 2, TimeUnit.MILLISECONDS) != testObject) {
throw new RuntimeException();
}
}
private static void takeTest() throws InterruptedException {
final LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
final Object testObject = new Object();
new Thread(new Runnable() {
@Override
public void run() {
try {
Thread.sleep(DELAY_TILL_ACTION);
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
}
lbq.add(testObject);
}
}).start();
if (lbq.take() != testObject) {
throw new RuntimeException();
}
}
private static void removeEmptyTest() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
try {
lbq.remove();
throw new RuntimeException("Exception should have thrown");
} catch (NoSuchElementException e) {
// expected
}
}
private static void removeTest() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
Object testObject = new Object();
lbq.add(testObject);
if (lbq.remove() != testObject) {
throw new RuntimeException();
}
}
private static void drainToTest() {
int objQty = 2;
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
for (int i = 0; i < objQty; i++) {
lbq.add(new Object());
}
LinkedList<Object> drainToResult = new LinkedList<Object>();
if (lbq.drainTo(drainToResult) != objQty) {
throw new RuntimeException();
} else if (drainToResult.size() != objQty) {
throw new RuntimeException();
}
}
private static void drainToLimitTest() {
int objQty = 4;
int limit = 2;
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
for (int i = 0; i < objQty; i++) {
lbq.add(new Object());
}
LinkedList<Object> drainToResult = new LinkedList<Object>();
if (lbq.drainTo(drainToResult, limit) != limit) {
throw new RuntimeException();
} else if (drainToResult.size() != limit) {
throw new RuntimeException();
} else if (lbq.size() != objQty - limit) {
throw new RuntimeException();
}
}
private static void containsTest() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
Object testObject = new Object();
if (lbq.contains(testObject)) {
throw new RuntimeException();
}
lbq.add(testObject);
if (! lbq.contains(testObject)) {
throw new RuntimeException();
}
}
private static void containsAllTest() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
Object testObject = new Object();
lbq.add(testObject);
LinkedList<Object> testList = new LinkedList<Object>();
testList.add(testObject);
testList.add(new Object());
if (lbq.containsAll(testList)) {
throw new RuntimeException();
}
lbq.addAll(testList);
if (! lbq.containsAll(testList)) {
throw new RuntimeException();
}
}
private static void removeObjectTest() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
Object testObject = new Object();
if (lbq.remove(testObject)) {
throw new RuntimeException();
}
lbq.add(testObject);
if (! lbq.remove(testObject)) {
throw new RuntimeException();
}
}
private static void removeAllTest() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
Object testObject = new Object();
lbq.add(testObject);
LinkedList<Object> testList = new LinkedList<Object>();
testList.add(testObject);
testList.add(new Object());
if (! lbq.removeAll(testList)) {
throw new RuntimeException();
}
lbq.addAll(testList);
if (! lbq.removeAll(testList)) {
throw new RuntimeException();
}
}
private static void clearTest() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
lbq.add(new Object());
lbq.clear();
if (! lbq.isEmpty()) {
throw new RuntimeException();
}
}
private static void toArrayTest() {
LinkedBlockingQueue<Object> lbq = new LinkedBlockingQueue<Object>();
if (lbq.toArray().length != 0) {
throw new RuntimeException();
}
Object testObject = new Object();
lbq.add(testObject);
Object[] result = lbq.toArray();
if (result.length != 1) {
throw new RuntimeException();
} else if (result[0] != testObject) {
throw new RuntimeException();
}
}
}