java面試題---請用多執行緒寫死鎖
阿新 • • 發佈：2019-01-26
java面試題---用多執行緒寫死鎖
（請參考本部落格對同步鎖的文章進行理解）列印輸出： 我進入了ThreadOne外部鎖public class dead { public static void main(String[] args) { // TODO Auto-generated method stub ThreadOne one=new ThreadOne(); ThreadTwo two=new ThreadTwo(); sharing obj1=new sharing(); sharing obj2=new sharing(); one.obj1=obj1; one.obj2=obj2; two.obj1=obj1; two.obj2=obj2; one.obj1=two.obj2; one.obj2=two.obj1; one.start(); two.start(); } } class sharing{ } class ThreadOne extends Thread{ sharing obj1; sharing obj2; public void run(){ synchronized (obj1) { System.out.println("我進入了ThreadOne外部鎖"); synchronized (obj2) { System.out.println("我進入了ThreadOne內部鎖"); } } } } class ThreadTwo extends Thread{ sharing obj1; sharing obj2; public void run(){ synchronized (obj1) { System.out.println("我進入了ThreadTwo外部鎖"); synchronized (obj2) { System.out.println("我進入了ThreadTwo內部鎖"); } } } }
我進入了ThreadTwo外部鎖 （兩個執行緒都在等在同步資源釋放自己的鎖，一直處於等待狀態）