这个线程能活着吗?以及如何使用java.lang.thread.join()方法

我以前读过一些SO问题和文档，但没有找到我的答案：

• 一个线程在java中能存活多久
• Java线程何时处于活动状态
• http://journals.ecs.soton.ac.uk/java/tutorial/java/threads/states.html

所以。。。

public class MyThread extends Thread {
public MyThread() {
this.setName("MyThread-" + System.currentTimeMillis());
this.start();
}
public MyThread(long millis) throws InterruptedException {
this.setName("MyThread-" + System.currentTimeMillis());
this.join(millis);
this.start();
}
@Override
public void run() {
System.out.println("I am running...");
// This thread does not sleep... no Thread.sleep() in run method.
// Do some things like requesting a database
// Database response happens in less time that the timeout
}
}
public class MyClass {
public MyClass(){
for (int i = 0; i < 5; i++) {
Thread t1 = new MyThread();
t1.join(5000);
if (t1.isAlive()) {
System.out.println("I'm alive");
// do some things
} else {
System.out.println("I'm not alive");
}
Thread t2 = new MyThread(5000);
if (t2.isAlive()) {
System.out.println("I'm alive");
// do some things
} else {
System.out.println("I'm not alive");
}
}
}
}

似乎不可能，但其中一个t1还活着吗？t2呢？当我在start()之后呼叫join()时发生了什么

有关信息，我使用：

• JVM:Java HotSpot(TM)客户端虚拟机(20.45-b01，混合模式，共享)
• Java：版本1.6.0_45，供应商Sun Microsystems股份有限公司

阅读部分回复后更新

如果我理解的话，更好的实现方式应该是：

public class MyThread extends Thread {
public MyThread() {
super("MyThread-" + System.currentTimeMillis());
}
@Override
public void run() {
System.out.println("I am running...");
// This thread does not sleep... no Thread.sleep() in run method.
// Do some things like requesting a database
// Database response happens in less time that the timeout
}
}
public class MyClass {
public MyClass(){
for (int i = 0; i < 5; i++) {
Thread t1 = new MyThread();
t1.start();
t1.join(5000);
if (t1.isAlive()) {
System.out.println("I'm alive");
// do some things
} else {
System.out.println("I'm not alive");
}
}
}
}

这两种回答对我帮助很大：https://stackoverflow.com/a/29775219/1312547和https://stackoverflow.com/a/29775083/1312547