PooledSjavac.java revision 2593:035b01d356ee 
1/*
2 * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25package com.sun.tools.sjavac.comp;
26
27import java.io.File;
28import java.net.URI;
29import java.util.List;
30import java.util.Objects;
31import java.util.Set;
32import java.util.concurrent.Callable;
33import java.util.concurrent.ExecutorService;
34import java.util.concurrent.Executors;
35import java.util.concurrent.ThreadFactory;
36import java.util.concurrent.TimeUnit;
37import java.util.concurrent.atomic.AtomicInteger;
38
39import com.sun.tools.sjavac.Log;
40import com.sun.tools.sjavac.server.CompilationResult;
41import com.sun.tools.sjavac.server.Sjavac;
42import com.sun.tools.sjavac.server.SysInfo;
43
44/**
45 * An sjavac implementation that limits the number of concurrent calls by
46 * wrapping invocations in Callables and delegating them to a FixedThreadPool.
47 *
48 *  <p><b>This is NOT part of any supported API.
49 *  If you write code that depends on this, you do so at your own risk.
50 *  This code and its internal interfaces are subject to change or
51 *  deletion without notice.</b>
52 */
53public class PooledSjavac implements Sjavac {
54
55    final Sjavac delegate;
56    final ExecutorService pool;
57
58    public PooledSjavac(Sjavac delegate, int poolsize) {
59        Objects.requireNonNull(delegate);
60        this.delegate = delegate;
61        pool = Executors.newFixedThreadPool(poolsize, new ThreadFactory() {
62            AtomicInteger count = new AtomicInteger();
63            @Override
64            public Thread newThread(Runnable runnable) {
65                String cls = PooledSjavac.class.getSimpleName();
66                int num = count.incrementAndGet();
67                Thread t = new Thread(runnable, cls + "-" + num);
68                t.setDaemon(true);
69                return t;
70            }
71        });
72    }
73
74    @Override
75    public SysInfo getSysInfo() {
76        try {
77            return pool.submit(new Callable<SysInfo>() {
78                @Override
79                public SysInfo call() throws Exception {
80                    return delegate.getSysInfo();
81                }
82            }).get();
83        } catch (Exception e) {
84            e.printStackTrace();
85            throw new RuntimeException("Error during getSysInfo", e);
86        }
87    }
88
89    @Override
90    public CompilationResult compile(final String protocolId,
91                                     final String invocationId,
92                                     final String[] args,
93                                     final List<File> explicitSources,
94                                     final Set<URI> sourcesToCompile,
95                                     final Set<URI> visibleSources) {
96        try {
97            return pool.submit(new Callable<CompilationResult>() {
98                @Override
99                public CompilationResult call() throws Exception {
100                    return delegate.compile(protocolId,
101                                            invocationId,
102                                            args,
103                                            explicitSources,
104                                            sourcesToCompile,
105                                            visibleSources);
106                }
107            }).get();
108        } catch (Exception e) {
109            e.printStackTrace();
110            throw new RuntimeException("Error during compile", e);
111        }
112    }
113
114    @Override
115    public void shutdown() {
116        pool.shutdown(); // Disable new tasks from being submitted
117        try {
118            // Wait a while for existing tasks to terminate
119            if (!pool.awaitTermination(60, TimeUnit.SECONDS)) {
120                pool.shutdownNow(); // Cancel currently executing tasks
121                // Wait a while for tasks to respond to being cancelled
122                if (!pool.awaitTermination(60, TimeUnit.SECONDS))
123                    Log.error("ThreadPool did not terminate");
124            }
125            // Grace period for thread termination
126            Thread.sleep(1000);
127        } catch (InterruptedException ie) {
128          // (Re-)Cancel if current thread also interrupted
129          pool.shutdownNow();
130          // Preserve interrupt status
131          Thread.currentThread().interrupt();
132        }
133
134        delegate.shutdown();
135    }
136
137    @Override
138    public String serverSettings() {
139        return delegate.serverSettings();
140    }
141}
142