Solution:

In this example,

public class DieLock{

public static Object t1 = new Object();

public static Object t2 = new Object();

publict static void main(String[] args) {

new Threado (){

@Override

public void run(){

synchronized(t1) {

System.out.println("Thread1 get t1");

try{

Thread.sleep(100);

}catch (Exception e)

synchronized(t2){

System.out.println("Thread2 get t2");

}

}

}

}.start()'

new Thread(){

@Override public void run(){

synchronized (t2) {

System.out.println("Thread2 get t2");

try {

Thread.sleep(100);

} catch (Exception e) {

}

synchronized (t1)

System.out.println("Thread2 get t1");

}

}

}

start();

}

}

a. I figure out from the problem that both wait for each other to release the lock they hold, and then wait until death. Likewise,

b. When it comes to avoiding deadlock; Avoid one thread acquiring multiple locks at the same time;

Avoid a thread occupying multiple resources in the lock at eh same time, and try to ensure that each lock occupies only one resource;

Try timing lock, use locktryLock(timeout) instead of using an internal locking mechanism;

Tor database lock locking, and unlocking must be in one database connection, otherwise, unlocking failure will occur.