Finalize方法

Finalize()方法只被对象调用一次，而且，就算你执行了System.gc(),对象也不一定就马上执行Finalize方法。

 

 

public class FinalizeTest {

	public static FinalizeTest SAVE_OK = null;
	
	@Override
	protected void finalize() throws Throwable {
		super.finalize();
		System.out.println("finalize method run");
		FinalizeTest.SAVE_OK = this;
	}
	
	public static void main(String[] args) throws Exception{
		SAVE_OK = new FinalizeTest(); //对象引用数为1
		
		SAVE_OK = null; //对象引用指数为0
		System.gc();
		Thread.sleep(1000); //Finalizer 方法优先级很低，暂停1秒
		if(SAVE_OK != null){
			System.out.println("live");
		}else{
			System.out.println("dead");
		}
		
		SAVE_OK = null; //对象引用指数为0
		System.gc();
		Thread.sleep(1000); //Finalizer 方法优先级很低，暂停1秒
		if(SAVE_OK != null){
			System.out.println("live");
		}else{
			System.out.println("dead");
		}
		
	}
}

output： 
finalize method run
live
dead