LeetCode Java 相关题目
交替打印
- 思路分析：类的核心状态是
arr、线程数量、数组下标 cursor、当前线程 id（循环更新）。
public class 交替打印数组 {
public static void main(String[] args) {
int[] arr= new int[]{1,2,3,4,5,6,7,8,9};
int m = 3;
Printer printer = new Printer(arr, m);
for(int i = 0;i<3;i++){
final int fi = i;
new Thread(new Runnable() {
@Override
public void run() {
printer.prient(fi);
}
}).start();
}
}
}
class Printer {
int[] arr;
int threadCounts;
int cursor;
int currentThreadId;
Printer(int[] arr, int count) {
this.arr = arr;
this.threadCounts = count;
this.cursor = 0;
this.currentThreadId = 0;
}
public void prient(int threadId) {
synchronized (this) {
while (true) {
// 不是当前线程 阻塞
while (true) {
if (cursor>=arr.length) {
break;
}
if (threadId == currentThreadId) {
break;
}
try {
this.wait();
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (cursor>=arr.length) {
this.notifyAll();
break;
}
// 打印, 修改cursor, 和 current id
System.out.println("ThreadId: "+threadId+'\t'+arr[cursor]);
cursor++;
currentThreadId = (currentThreadId + 1) % threadCounts;
this.notifyAll();
}
}
}
}