JAVA多线程设计模式九 Future Pattern
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public class Host { public Data request(final int count, final char c) { System.out.println(" request(" + count + ", " + c + ") BEGIN"); // (1) 建立FutureData的实体 final FutureData future = new FutureData(); // (2) 为了建立RealData的实体，启动新的线程 new Thread() { public void run() { RealData realdata = new RealData(count, c); future.setRealData(realdata); } }.start(); System.out.println(" request(" + count + ", " + c + ") END"); // (3) 取回FutureData实体，作为传回值 return future; }}?
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public interface Data { public abstract String getContent();}?
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public class FutureData implements Data { private RealData realdata = null; private boolean ready = false; public synchronized void setRealData(RealData realdata) { if (ready) { return; // balk } this.realdata = realdata; this.ready = true; notifyAll(); } public synchronized String getContent() { while (!ready) { try { wait(); } catch (InterruptedException e) { } } return realdata.getContent(); }}?
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public class RealData implements Data { private final String content; public RealData(int count, char c) { System.out.println(" making RealData(" + count + ", " + c + ") BEGIN"); char[] buffer = new char[count]; for (int i = 0; i < count; i++) { buffer[i] = c; try { Thread.sleep(100); } catch (InterruptedException e) { } } System.out.println(" making RealData(" + count + ", " + c + ") END"); this.content = new String(buffer); } public String getContent() { return content; }}?
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public class Main { public static void main(String[] args) { System.out.println("main BEGIN"); Host host = new Host(); Data data1 = host.request(10, 'A'); Data data2 = host.request(20, 'B'); Data data3 = host.request(30, 'C'); System.out.println("main otherJob BEGIN"); try { Thread.sleep(2000); } catch (InterruptedException e) { } System.out.println("main otherJob END"); System.out.println("data1 = " + data1.getContent()); System.out.println("data2 = " + data2.getContent()); System.out.println("data3 = " + data3.getContent()); System.out.println("main END"); }}?