Java基础——多个线程共享数据

1，当多个线程需要操作同一个数据时（例如：火车站窗口卖票，有窗口在售票，有窗口在退票，他们操作的是同一堆票）

由于这里在做两种不同的操作，因此一个run()方法难免会使代码变得复杂，因此我们在MulitiThread中定义两个内部类实现runnable接口，分别进行不同的操作：

public class MultiThreadShareData {

public static void main(String[] args) {

Data data = new Data(100);
new Thread(new IncRunnable(data)).start();
new Thread(new DecRunnable(data)).start();
new Thread(new DecRunnable(data)).start();

}

private static synchronized void increase(Data data) {
data.inc();
}

private static synchronized void decrease(Data data) {
data.dec();
}

static class IncRunnable implements Runnable {
private Data data;

public IncRunnable(Data data) {
this.data = data;
}

@Override
public void run() {
while (true) {
try {
Thread.sleep(500);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
increase(data);
System.out.println("inc " + data);
}
}
}

static class DecRunnable implements Runnable {
private Data data;

public DecRunnable(Data data) {
this.data = data;
}

@Override
public void run() {
while (true) {
try {
Thread.sleep(500);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
decrease(data);
System.out.println("Dec " + data);
}
}
}

}

class Data {
public int data;

public Data(int data) {
this.data = data;
}

public void inc() {
this.data++;
}

public void dec() {
this.data--;
}

@Override
public String toString() {
return " " + data;
}
}