util/concurrent/AbstractExecutorService.java

/*
 * Written by Doug Lea with assistance from members of JCP JSR-166
 * Expert Group and released to the public domain. Use, modify, and
 * redistribute this code in any way without acknowledgement.
 */

package java.util.concurrent;

import java.util.*;

/**
 * Provides default implementation of {@link ExecutorService}
 * execution methods. This class implements the <tt>submit</tt>,
 * <tt>invokeAny</tt> and <tt>invokeAll</tt> methods using the default
 * {@link FutureTask} class provided in this package.  For example,
 * the the implementation of <tt>submit(Runnable)</tt> creates an
 * associated <tt>FutureTask</tt> that is executed and
 * returned. Subclasses overriding these methods to use different
 * {@link Future} implementations should do so consistently for each
 * of these methods.
 *
 * @since 1.5
 * @author Doug Lea
 */
public abstract class AbstractExecutorService implements ExecutorService {

    public Future<?> submit(Runnable task) {
        FutureTask<Object> ftask = new FutureTask<Object>(task, null);
        execute(ftask);
        return ftask;
    }

    public <T> Future<T> submit(Callable<T> task) {
        FutureTask<T> ftask = new FutureTask<T>(task);
        execute(ftask);
        return ftask;
    }

    // any/all methods, each a little bit different than the other


    public <T> T invokeAny(Collection<Callable<T>> tasks)
        throws InterruptedException, ExecutionException {
        if (tasks == null)
            throw new NullPointerException();
        int n = tasks.size();
        if (n == 0)
            throw new IllegalArgumentException();
        List<Future<T>> futures= new ArrayList<Future<T>>(n);
        ExecutorCompletionService<T> ecs = 
            new ExecutorCompletionService<T>(this);
        try {
            for (Callable<T> t : tasks) 
                futures.add(ecs.submit(t));
            ExecutionException ee = null;
            RuntimeException re = null;
            while (n-- > 0) {
                Future<T> f = ecs.take();
                try {
                    return f.get();
                } catch(ExecutionException eex) {
                    ee = eex;
                } catch(RuntimeException rex) {
                    re = rex;
                }
            }    
            if (ee != null)
                throw ee;
            if (re != null)
                throw new ExecutionException(re);
            throw new ExecutionException();
        } finally {
            for (Future<T> f : futures) 
                f.cancel(true);
        }
    }

    public <T> T invokeAny(Collection<Callable<T>> tasks, 
                           long timeout, TimeUnit unit) 
        throws InterruptedException, ExecutionException, TimeoutException {
        if (tasks == null || unit == null)
            throw new NullPointerException();
        long nanos = unit.toNanos(timeout);
        int n = tasks.size();
        if (n == 0)
            throw new IllegalArgumentException();
        List<Future<T>> futures= new ArrayList<Future<T>>(n);
        ExecutorCompletionService<T> ecs = 
            new ExecutorCompletionService<T>(this);
        try {
            for (Callable<T> t : tasks) 
                futures.add(ecs.submit(t));
            ExecutionException ee = null;
            RuntimeException re = null;
            long lastTime = System.nanoTime();
            while (n-- > 0) {
                Future<T> f = ecs.poll(nanos, TimeUnit.NANOSECONDS);
                if (f == null)
                    throw new TimeoutException();
                try {
                    return f.get();
                } catch(ExecutionException eex) {
                    ee = eex;
                } catch(RuntimeException rex) {
                    re = rex;
                }
                long now = System.nanoTime();
                nanos -= now - lastTime;
                lastTime = now;
            }    
            if (ee != null)
                throw ee;
            if (re != null)
                throw new ExecutionException(re);
            throw new ExecutionException();
        } finally {
            for (Future<T> f : futures) 
                f.cancel(true);
        }
    }

    public <T> List<Future<T>> invokeAll(Collection<Callable<T>> tasks)
        throws InterruptedException {
        if (tasks == null)
            throw new NullPointerException();
        List<Future<T>> futures = new ArrayList<Future<T>>(tasks.size());
        boolean done = false;
        try {
            for (Callable<T> t : tasks) {
                FutureTask<T> f = new FutureTask<T>(t);
                futures.add(f);
                execute(f);
            }
            for (Future<T> f : futures) {
                if (!f.isDone()) {
                    try { 
                        f.get(); 
                    } catch(CancellationException ignore) {
                    } catch(ExecutionException ignore) {
                    }
                }
            }
            done = true;
            return futures;
        } finally {
            if (!done)
                for (Future<T> f : futures) 
                    f.cancel(true);
        }
    }

    public <T> List<Future<T>> invokeAll(Collection<Callable<T>> tasks, 
                                         long timeout, TimeUnit unit) 
        throws InterruptedException {
        if (tasks == null || unit == null)
            throw new NullPointerException();
        long nanos = unit.toNanos(timeout);
        List<Future<T>> futures = new ArrayList<Future<T>>(tasks.size());
        boolean done = false;
        try {
            for (Callable<T> t : tasks) {
                FutureTask<T> f = new FutureTask<T>(t);
                futures.add(f);
                execute(f);
            }
            long lastTime = System.nanoTime();
            for (Future<T> f : futures) {
                if (!f.isDone()) {
                    if (nanos < 0) 
                        return futures; 
                    try { 
                        f.get(nanos, TimeUnit.NANOSECONDS); 
                    } catch(CancellationException ignore) {
                    } catch(ExecutionException ignore) {
                    } catch(TimeoutException toe) {
                        return futures;
                    }
                    long now = System.nanoTime();
                    nanos -= now - lastTime;
                    lastTime = now;
                }
            }
            done = true;
            return futures;
        } finally {
            if (!done)
                for (Future<T> f : futures) 
                    f.cancel(true);
        }
    }

}
Revision:	1.12
Committed:	Sat Dec 20 14:00:05 2003 UTC (20 years, 5 months ago) by dl
Branch:	MAIN
Changes since 1.11:	+5 -16 lines
Log Message:	Replace PrivilegedFutureTask with Executors.privilegedCallable
#	User	Rev	Content
1	tim	1.1	/*
2			* Written by Doug Lea with assistance from members of JCP JSR-166
3			* Expert Group and released to the public domain. Use, modify, and
4			* redistribute this code in any way without acknowledgement.
5			*/
6
7			package java.util.concurrent;
8
9	dl	1.3	import java.util.*;
10	tim	1.1
11			/**
12	dl	1.2	* Provides default implementation of {@link ExecutorService}
13	dl	1.12	* execution methods. This class implements the <tt>submit</tt>,
14			* <tt>invokeAny</tt> and <tt>invokeAll</tt> methods using the default
15			* {@link FutureTask} class provided in this package. For example,
16			* the the implementation of <tt>submit(Runnable)</tt> creates an
17			* associated <tt>FutureTask</tt> that is executed and
18	dl	1.2	* returned. Subclasses overriding these methods to use different
19			* {@link Future} implementations should do so consistently for each
20			* of these methods.
21	tim	1.1	*
22			* @since 1.5
23			* @author Doug Lea
24			*/
25			public abstract class AbstractExecutorService implements ExecutorService {
26
27	dl	1.11	public Future<?> submit(Runnable task) {
28			FutureTask<Object> ftask = new FutureTask<Object>(task, null);
29	tim	1.1	execute(ftask);
30			return ftask;
31			}
32
33			public <T> Future<T> submit(Callable<T> task) {
34			FutureTask<T> ftask = new FutureTask<T>(task);
35			execute(ftask);
36			return ftask;
37			}
38
39	dl	1.7	// any/all methods, each a little bit different than the other
40	dl	1.3
41
42	dl	1.7	public <T> T invokeAny(Collection<Callable<T>> tasks)
43			throws InterruptedException, ExecutionException {
44	dl	1.3	if (tasks == null)
45			throw new NullPointerException();
46			int n = tasks.size();
47			if (n == 0)
48	dl	1.7	throw new IllegalArgumentException();
49			List<Future<T>> futures= new ArrayList<Future<T>>(n);
50			ExecutorCompletionService<T> ecs =
51			new ExecutorCompletionService<T>(this);
52	dl	1.3	try {
53	dl	1.7	for (Callable<T> t : tasks)
54			futures.add(ecs.submit(t));
55			ExecutionException ee = null;
56			RuntimeException re = null;
57			while (n-- > 0) {
58			Future<T> f = ecs.take();
59			try {
60			return f.get();
61			} catch(ExecutionException eex) {
62			ee = eex;
63			} catch(RuntimeException rex) {
64			re = rex;
65			}
66			}
67			if (ee != null)
68			throw ee;
69			if (re != null)
70			throw new ExecutionException(re);
71			throw new ExecutionException();
72	dl	1.3	} finally {
73	dl	1.6	for (Future<T> f : futures)
74	dl	1.4	f.cancel(true);
75	dl	1.3	}
76			}
77
78	dl	1.7	public <T> T invokeAny(Collection<Callable<T>> tasks,
79			long timeout, TimeUnit unit)
80			throws InterruptedException, ExecutionException, TimeoutException {
81	dl	1.3	if (tasks == null \|\| unit == null)
82			throw new NullPointerException();
83	dl	1.7	long nanos = unit.toNanos(timeout);
84	dl	1.3	int n = tasks.size();
85			if (n == 0)
86	dl	1.7	throw new IllegalArgumentException();
87			List<Future<T>> futures= new ArrayList<Future<T>>(n);
88			ExecutorCompletionService<T> ecs =
89			new ExecutorCompletionService<T>(this);
90	dl	1.3	try {
91	dl	1.7	for (Callable<T> t : tasks)
92			futures.add(ecs.submit(t));
93			ExecutionException ee = null;
94			RuntimeException re = null;
95			long lastTime = System.nanoTime();
96			while (n-- > 0) {
97			Future<T> f = ecs.poll(nanos, TimeUnit.NANOSECONDS);
98	dl	1.8	if (f == null)
99			throw new TimeoutException();
100	dl	1.7	try {
101			return f.get();
102			} catch(ExecutionException eex) {
103			ee = eex;
104			} catch(RuntimeException rex) {
105			re = rex;
106			}
107	dl	1.8	long now = System.nanoTime();
108			nanos -= now - lastTime;
109			lastTime = now;
110	dl	1.7	}
111			if (ee != null)
112			throw ee;
113			if (re != null)
114			throw new ExecutionException(re);
115			throw new ExecutionException();
116	dl	1.3	} finally {
117	dl	1.6	for (Future<T> f : futures)
118	dl	1.4	f.cancel(true);
119	dl	1.3	}
120			}
121
122	dl	1.9	public <T> List<Future<T>> invokeAll(Collection<Callable<T>> tasks)
123	dl	1.3	throws InterruptedException {
124			if (tasks == null)
125			throw new NullPointerException();
126	dl	1.6	List<Future<T>> futures = new ArrayList<Future<T>>(tasks.size());
127			boolean done = false;
128	dl	1.3	try {
129			for (Callable<T> t : tasks) {
130	dl	1.6	FutureTask<T> f = new FutureTask<T>(t);
131	dl	1.3	futures.add(f);
132			execute(f);
133			}
134	dl	1.6	for (Future<T> f : futures) {
135			if (!f.isDone()) {
136			try {
137			f.get();
138			} catch(CancellationException ignore) {
139			} catch(ExecutionException ignore) {
140			}
141			}
142			}
143			done = true;
144	dl	1.3	return futures;
145			} finally {
146	dl	1.6	if (!done)
147	dl	1.4	for (Future<T> f : futures)
148			f.cancel(true);
149	dl	1.3	}
150			}
151
152	dl	1.9	public <T> List<Future<T>> invokeAll(Collection<Callable<T>> tasks,
153	dl	1.6	long timeout, TimeUnit unit)
154	dl	1.3	throws InterruptedException {
155			if (tasks == null \|\| unit == null)
156			throw new NullPointerException();
157			long nanos = unit.toNanos(timeout);
158	dl	1.6	List<Future<T>> futures = new ArrayList<Future<T>>(tasks.size());
159			boolean done = false;
160	dl	1.3	try {
161			for (Callable<T> t : tasks) {
162	dl	1.6	FutureTask<T> f = new FutureTask<T>(t);
163	dl	1.3	futures.add(f);
164			execute(f);
165			}
166	dl	1.6	long lastTime = System.nanoTime();
167			for (Future<T> f : futures) {
168			if (!f.isDone()) {
169			if (nanos < 0)
170			return futures;
171			try {
172			f.get(nanos, TimeUnit.NANOSECONDS);
173			} catch(CancellationException ignore) {
174			} catch(ExecutionException ignore) {
175			} catch(TimeoutException toe) {
176			return futures;
177			}
178	dl	1.8	long now = System.nanoTime();
179			nanos -= now - lastTime;
180			lastTime = now;
181	dl	1.6	}
182			}
183			done = true;
184	dl	1.3	return futures;
185			} finally {
186	dl	1.6	if (!done)
187	dl	1.4	for (Future<T> f : futures)
188			f.cancel(true);
189	dl	1.3	}
190			}
191
192	tim	1.1	}