如何获取正在运行的线程的ID？(How to get the Id of the running thread?)
问题描述 (Problem Description)
如何获取正在运行的线程的ID？
解决方案 (Solution)
下面的示例演示如何使用getThreadId（）方法获取正在运行的线程的Id。
public class Main extends Object implements Runnable {
private ThreadID var;
public Main(ThreadID v) {
this.var = v;
}
public void run() {
try {
print("var getThreadID =" + var.getThreadID());
Thread.sleep(2000);
print("var getThreadID =" + var.getThreadID());
} catch (InterruptedException x) {}
}
private static void print(String msg) {
String name = Thread.currentThread().getName();
System.out.println(name + ": " + msg);
}
public static void main(String[] args) {
ThreadID tid = new ThreadID();
Main shared = new Main(tid);
try {
Thread threadA = new Thread(shared, "threadA");
threadA.start();
Thread.sleep(500);
Thread threadB = new Thread(shared, "threadB");
threadB.start();
Thread.sleep(500);
Thread threadC = new Thread(shared, "threadC");
threadC.start();
} catch (InterruptedException x) {}
}
}
class ThreadID extends ThreadLocal {
private int nextID;
public ThreadID() {
nextID = 10001;
}
private synchronized Integer getNewID() {
Integer id = new Integer(nextID);
nextID++;
return id;
}
protected Object initialValue() {
print("in initialValue()");
return getNewID();
}
public int getThreadID() {
Integer id = (Integer) get();
return id.intValue();
}
private static void print(String msg) {
String name = Thread.currentThread().getName();
System.out.println(name + ": " + msg);
}
}
结果 (Result)
上面的代码示例将产生以下结果。
threadA: in initialValue()
threadA: var getThreadID =10001
threadB: in initialValue()
threadB: var getThreadID =10002
threadC: in initialValue()
threadC: var getThreadID =10003
threadA: var getThreadID =10001
threadB: var getThreadID =10002
threadC: var getThreadID =10003
