一间大屋子有两个功能：睡觉、学习，互不相干
现在小南要学习，小女要睡觉，但如果只用一间屋子（一个对象锁）的话，那么并发度很低
细化前
例如：
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| class BigRoom {
public void sleep() {
synchronized (this) {
log.debug("sleeping 2 小时");
Sleeper.sleep(2);
}
}
public void study() {
synchronized (this) {
log.debug("study 1 小时");
Sleeper.sleep(1);
}
}
}
|
执行:
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| BigRoom bigRoom = new BigRoom();
new Thread(() -> {
bigRoom.compute();
},"小南").start();
new Thread(() -> {
bigRoom.sleep();
},"小女").start();
|
某次结果:
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| 12:13:54.471 [小南] c.BigRoom - study 1 小时
12:13:55.476 [小女] c.BigRoom - sleeping 2 小时
|
细化后
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| class BigRoom {
private final Object studyRoom = new Object();
private final Object bedRoom = new Object();
public void sleep() {
synchronized (bedRoom) {
log.debug("sleeping 2 小时");
Sleeper.sleep(2);
}
}
public void study() {
synchronized (studyRoom) {
log.debug("study 1 小时");
Sleeper.sleep(1);
}
}
}
|
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| 12:15:35.069 [小南] c.BigRoom - study 1 小时
12:15:35.069 [小女] c.BigRoom - sleeping 2 小时
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将锁的粒度细分
