61 lines
1.5 KiB
Java
61 lines
1.5 KiB
Java
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class TLtest extends Thread {
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public static void main (String [] args) {
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Data d = new Data ();
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new ThreadTest (d, "A").start ();
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new ThreadTest (d, "B").start ();
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}
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}
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class Data {
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private static ThreadLocal owner = new ThreadLocal () {
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public Object initialValue () { return ("0"); }
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};
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/* A thread will call `set' to set a value it wants an instance
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of Data to associate with it and only it. */
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synchronized public void set (String v){owner.set (v);}
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/* A thread will call `get' to get a value it wants an instance
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of Data to associate with it and only it. */
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synchronized public String get (){return (String)owner.get();}
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}
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class ThreadTest extends Thread {
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public Data d;
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ThreadTest (Data d, String name) {
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super (name);
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this.d = d;
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}
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public void run () {
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int value = 0;
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int ref = 0;
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for (int i = 0; i < 20; i++) {
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int rand = (int)(Math.random ()*20);
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/* Read `value', ref is kept for comparison */
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value = Integer.parseInt (d.get());
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/* change `value' and ref by a random number, store `value'. */
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value += rand; ref += rand;
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d.set (Integer.toString (value));
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try {
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sleep((int)(Math.random() * 500));
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} catch (InterruptedException e) {}
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}
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/* If a thread didn't have private value to attach to the
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instance of Data, results wouldn't be the same */
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if (ref == value)
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System.out.println ("test OK.");
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else
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System.out.println ("test failed.");
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}
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}
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