线程同步方法一（ReentrantLock）

package com.yli.thread.lock;

/**
 * 不加锁,在两个账户之间转账,多次运行会发现两个账号的总额由变化
 * 
 * @author yli
 * 
 */
public class UnLockTest {
	public static final int TOTAL_AMOUNT = 100000;

	public static void main(String[] args) {
		Bank1 bank = new Bank1("yli", 100000);
		Bank1 targetBank = new Bank1("ylz", 0);
		System.out.println(Thread.currentThread().getName() + "=========>总额="
				+ (bank.getBalance() + targetBank.getBalance()));
		for (int i = 0; i < 20000; i++) {
			TransferBank1 transfer = new TransferBank1(bank, targetBank, 5);
			Thread thread = new Thread(transfer);
			thread.setName("Transfer-" + i);
			thread.start();
		}
	}
}

class TransferBank1 implements Runnable {

	private Bank1 bank;
	private Bank1 targetBank;
	private int amount;

	public TransferBank1(Bank1 bank, Bank1 targetBank, int amount) {
		this.bank = bank;
		this.targetBank = targetBank;
		this.amount = amount;
	}

	@Override
	public void run() {
		this.bank.transferAccount(targetBank, amount);
	}

}

class Bank1 {

	private String name;
	private int balance;

	public Bank1(String name, int balance) {
		this.name = name;
		this.balance = balance;
	}

	public void transferAccount(Bank1 targetBank, int amount) {
		this.balance -= amount;
		targetBank.balance += amount;
		int total = this.getBalance() + targetBank.getBalance();
		System.out.println(Thread.currentThread().getName() + "=========>总额="	+ total);
		if (total != UnLockTest.TOTAL_AMOUNT) {
			Thread.currentThread().interrupt();
			try {
				throw new InterruptedException("================>转账错误,抛出异常");
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
		}
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public int getBalance() {
		return balance;
	}

	public void setBalance(int balance) {
		this.balance = balance;
	}

}

 

================================华丽丽的分割线=====================================

 

package com.yli.thread.lock;

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

/**
 * 加锁,两个账户之间转账没有影响
 * @author yli
 *
 */
public class ReentLockTest {
	public static final int TOTAL_AMOUNT = 100000;
	
	public static void main(String[] args) {
		Bank bank = new Bank("yli", TOTAL_AMOUNT);
		Bank targetBank = new Bank("ylz", 0);
		System.out.println(Thread.currentThread().getName() + "=========>总额="	+ (bank.getBalance() + targetBank.getBalance()));
		for (int i = 0; i < 20000; i++) {
			TransferBank transfer = new TransferBank(bank, targetBank, 5);
			Thread thread = new Thread(transfer);
			thread.setName("Transfer-" + i);
			thread.start();
		}
	}
}

class TransferBank implements Runnable {

	private Bank bank;
	private Bank targetBank;
	private int amount;

	public TransferBank(Bank bank, Bank targetBank, int amount) {
		this.bank = bank;
		this.targetBank = targetBank;
		this.amount = amount;
	}

	@Override
	public void run() {
		this.bank.transferAccount(targetBank, amount);
	}

}

class Bank {

	private String name;
	private int balance;
	private Lock transferLock;
	private Condition transferCon;

	public Bank(String name, int balance) {
		this.name = name;
		this.balance = balance;
		this.transferLock = new ReentrantLock();
		this.transferCon = this.transferLock.newCondition();
	}

	public void transferAccount(Bank targetBank, int amount) {
		this.transferLock.lock();

		try {
			while (this.balance < amount) {
				this.transferCon.await();
			}
		} catch (InterruptedException e) {
			e.printStackTrace();
		}

		this.balance -= amount;
		targetBank.balance += amount;
		int total = this.getBalance() + targetBank.getBalance();
		System.out.println(Thread.currentThread().getName() + "=========>总额="	+ total);
		if(total != ReentLockTest.TOTAL_AMOUNT){
			Thread.currentThread().interrupt();
			try {
				throw new InterruptedException("================>转账错误,停止运行");
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
		}

		this.transferCon.signalAll();

		this.transferLock.unlock();
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public int getBalance() {
		this.transferLock.lock();
		try {
			return balance;
		} finally {
			this.transferLock.unlock();
		}
	}

	public void setBalance(int balance) {
		this.balance = balance;
	}

}