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2, µÚÒ»¸öÏ߳̽«¶ÔÏówait
3, µÚ¶þ¸öÏß³ÌÔÙ½«¶ÔÏónotify
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1, µÚÒ»¸öÏß³ÌÅжϸöÔÏóÊÇ·ñÒªwait
2, µÚ¶þ¸öÏ߳̽«¶ÔÏónotify
3, µÚÒ»¸öÏ߳̽«¶ÔÏówait
ΪÁË·ÀÖ¹ÕâЩÇé¿ö£¬²ÅÐèÒªÔÚwaitÓënotify֮ǰ¼Ósynchronized
java ´úÂë
A a = A.getInstance();//µ¥Àý¶ÔÏó,ͬһ·ÝʵÀý²»Ïú»Ù
synchronized (a) {
a.wait();
}
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A a = A.getInstance();
synchronized(a) {
a.notify();
}
µÈ´ý-֪ͨ»úÖƱØÐëÓësychronizedÒ»ÆðÓÃ,·ñÔò×ÔÉíÒ²»áÓÐ race condition.
2, ¾²Ì¬Í¬²½·½·¨Óë·Ç¾²Ì¬Í¬²½·½·¨µÄÇø±ð
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ÒµÎñÂß¼­µÄ·â×°Àà:
public class Logic {
private static final Log log = LogFactory.getLog(Logic.class);
private static Logic logic;
 
private Logic() {}
 
public static Logic getInstance() {
if (null == logic) {
logic = new Logic();
}
 
return logic;
}
 
public static synchronized void testStatic() {
log.info(Thread.currentThread().getName() + " : static method is running");
}
 
public synchronized void testNonStatic() {
log.info(Thread.currentThread().getName() + " : non static method is running");
}
}
·Ç¾²Ì¬·½·¨µÄÖ´ÐÐ:
public class ThreadRun1 extends Thread {
private static final Log log = LogFactory.getLog(ThreadRun1.class);
 
public void run() {
Logic logic = Logic.getInstance(); // object reference
 
try {
Thread.sleep(3000);
} catch (InterruptedException e) {
log.error("some exceptions occured :", e);
}
 
logic.testNonStatic();
 
logEnd();
}
 
private void logEnd() {
log.info("thread ru