注意點：1.作為物件鎖，寫在Account裡面和外面不一樣，寫在裡面是該類方法只會公用該類物件的鎖，寫在外面表示所有物件都公用那一個鎖，不同使用者公用一個鎖，顯然是不對的。所以寫在裡面表示每個使用者的取錢和存錢共享鎖，和其它的使用者物件沒有關係，因為公用的鎖不一樣。

2. 對於lock 鎖一定注意不能用static 修飾，這樣和寫在Account 外面是一樣的，其它的使用者也可以呼叫另外一個使用者的lock物件做為鎖，影響到其它使用者了，也會導致執行緒報錯。

3. 對於百萬使用者同時存錢取錢的，用lock ,同步量少的用syncronized,這裡測試的lock 為5.8秒，sy為7.3秒

@RequestMapping(value="/testMoney3",method=RequestMethod.GET)
@ResponseBody
public int testThread3() {
long time =System.currentTimeMillis();
int i=1000000;
int money=0;
while(i>2) {
MyAccount myAccount=new MyAccount();
new Thread() {
public void run() {
myAccount.saveMoney(m);
// System.out.println("baocun:"+myAccount.getMoney());
myAccount.delMoney(m);
// System.out.println("shanchu:"+myAccount.getMoney());
}
}.start();
i--;
money=myAccount.getMoney();
}
// int money=myAccount.getMoney();
// System.out.println(myAccount.getMoney());
long time2 =System.currentTimeMillis();
System.out.println("用時:"+(time2-time));
return money;
}

// @RequestMapping(value="/testMoneyOther",method=RequestMethod.GET)
// @ResponseBody
// public int testThread2() {
// int i=1000000;
// int money=0;

// long time =System.currentTimeMillis();

//               MyAccount myAccount=new MyAccount();    

// while(i>2) {
// myAccount.saveMoney(m);
// myAccount.delMoney(m);
// money=myAccount.getMoney();
// System.out.println(myAccount.getMoney());
// i--;
// }
// long time2 =System.currentTimeMillis();
// System.out.println("用時:"+(time2-time)/1000);
// return money;

// }

package com.example.demo.lockp;


import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;


import org.springframework.stereotype.Component;




public class MyAccount {

  private int money =10000;


private  Lock lock = new ReentrantLock();
private  Condition condition = lock.newCondition();
private  Obj obj = new Obj();
   private boolean flage=true;


public int getMoney() {
return money;
}



public  Obj getObj() {
return obj;
}


public void saveMoney(int m) {
lock.lock();
try {
if(obj.getState()==1) {
money+=m;
obj.setState(2);
condition.signal();
}else if(obj.getState()==2){
condition.wait();
}
} catch (InterruptedException e) {
e.printStackTrace();
}finally {
lock.unlock();
}
}

   
public void delMoney(int m) {
lock.lock();
while(money<100&&money-m<0) {
flage=false;
}
if(!flage) {
try {
throw new Exception("ssss");
} catch (Exception e) {
e.printStackTrace();
}
}
try {
if(obj.getState()==2) {
money-=m;
obj.setState(1);
condition.signal();
}else if(obj.getState()==1){
condition.wait();
}
} catch (InterruptedException e) {
e.printStackTrace();
}finally {
lock.unlock();
}
}

// //設定引數
// public void setParm(Obj obj, Lock lock, Condition condition) {
// this.obj = obj;
// this.lock = lock;
// this.condition = condition;
// }



public void saveMoney123(int m) {
synchronized (this) {
money+=m;
notifyAll();
}
}


public void delMoney123(int m) {
synchronized (this) {
money-=m;
notifyAll();
}
}







}



package com.example.demo.lockp;


import org.springframework.stereotype.Component;


public class Obj {
public int state = 1;


public int getState() {
return state;
}


public void setState(int state) {
this.state = state;
}


}