void setMaxPriority(int pri)
描述 (Description)
java.lang.ThreadGroup.setMaxPriority()方法设置组的最大优先级。已经具有更高优先级的线程组中的线程不受影响。
声明 (Declaration)
以下是java.lang.ThreadGroup.setMaxPriority()方法的声明
public final void setMaxPriority(int pri)
参数 (Parameters)
pri - 这是线程组的新优先级。
返回值 (Return Value)
此方法不返回任何值。
异常 (Exception)
SecurityException - 如果当前线程无法修改此线程组。
例子 (Example)
以下示例显示了java.lang.ThreadGroup.setMaxPriority()方法的用法。
package com.iowiki;
import java.lang.*;
public class ThreadGroupDemo implements Runnable {
public static void main(String[] args) {
ThreadGroupDemo tg = new ThreadGroupDemo();
tg.func();
}
public void func() {
try {
// create a parent ThreadGroup
ThreadGroup pGroup = new ThreadGroup("Parent ThreadGroup");
// set maximum priority as 8 for Parent
pGroup.setMaxPriority(Thread.MAX_PRIORITY - 2);
// create a child ThreadGroup for parent ThreadGroup
ThreadGroup cGroup = new ThreadGroup(pGroup, "Child ThreadGroup");
// set maximum priority as 5 for child
cGroup.setMaxPriority(Thread.NORM_PRIORITY);
// create a thread with Priority as MAX
Thread t1 = new Thread(pGroup, this);
t1.setPriority(Thread.MAX_PRIORITY);
System.out.println("Starting " + t1.getName() + "...");
t1.start();
// create another thread with Priority as MAX
Thread t2 = new Thread(cGroup, this);
t1.setPriority(Thread.MAX_PRIORITY);
System.out.println("Starting " + t2.getName() + "...");
t2.start();
// display the number of active threads with actual priority
System.out.println("Active threads in \"" + pGroup.getName()
+ "\" = " + pGroup.activeCount());
// block until the other threads finish
t1.join();
t2.join();
} catch (InterruptedException ex) {
System.out.println(ex.toString());
}
}
// implements run()
public void run() {
for(int i = 0;i < 1000;i++) {
i++;
}
System.out.println(Thread.currentThread().getName() +
" [priority = " + Thread.currentThread().getPriority() +
"] finished executing.");
}
}
让我们编译并运行上面的程序,这将产生以下结果 -
Starting Thread-0...
Starting Thread-1...
Active threads in group "Parent ThreadGroup" = 2
Thread-0 [priority = 8] finished executing.
Thread-1 [priority = 5] finished executing.