不多说,先上代码,有几点疑问,当我将if语句写为if(flag)或if(flag==true)时,运行结果均为if locka与else lockb,即发生死锁。而当我将if语句写为if(flag=true)时,运行结果却为if locka ; if lockb;if locka;if lockb,这是为什么呢?
class test implements Runnable
{ private boolean flag;
test(boolean flag)
{
this.flag=flag;
}
public void run()
{
if(flag==true)
{
synchronized(lock.locka)
{ System.out.println("if locka");
synchronized(lock.lockb)
{
System.out.println("if lockb");
}
}
}
else
{synchronized(lock.lockb)
{ System.out.println("else lockb");
synchronized(lock.locka)
{
System.out.println("else locka");
}
}
}
}
}
class lock
{ static Object locka=new Object();
static Object lockb=new Object();
}
class DeathDemo
{
public static void main(String[] args)
{
Thread t1=new Thread(new test(true));
Thread t2=new Thread(new test(false));
t1.start();
t2.start();
}
}
|