静态方法内的同步块将获取类级别锁或对象级别锁
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在下面的代码片段中，我有一个问题。线程将获取类级别锁或对象级别锁？
private static Object lock=new Object();
private static Object lock2=new Object();
public static void m1()
synchronized(lock)
//statements
public static void m2()
synchronized(lock2)
//statements
每个对象都有一个“监视器”。使用同步块时，请指定要在其上同步其监视器的实例。除了同步的块，还有同步的方法。同步的[[instance方法将获取该方法在其上被调用的实例的监视器，而同步的[[static方法将获取该封闭类的java.lang.Class对象的监视器。]public class Foo
private static final Object STATIC_LOCK = new Object();
private final Object instanceLock = new Object();
public static void bar()
synchronized (STATIC_LOCK) // acquires monitor of "STATIC_LOCK" instance
// guarded code
public static synchronized void baz() // acquires monitor of "Foo.class" instance
// guarded code
public void qux()
synchronized (instanceLock) // acquires monitor of "instanceLock" instance
// guarded code
public synchronized void quux() // acquires monitor of "this" instance
// guarded code
public class Test
private static Object lock2 = new Object();
public synchronized void m1()
// Lock on current object instance(this) as this is an instance method
public synchronized static void m2()
// Lock at class level as this is a static method
public static void m3()
synchronized (lock2)
// Lock on `lock2` object. It doesn't make a difference if this method
// is static or not at the time of acquiring lock on a given object here
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