java的线程

多任务与多线程：多任务属于系统级的各个应用之间的关系，而多线程属于应用级的一个应用的多个功能之间的关系

创建线程的两种方式：

实现Runnable接口

class sunclass {}

class SumThread extends sumclass imlements Runnable{}

public class **{public void main(){SumThread st=new SumThread（）；Thread t=new Thread(st,"threadname");t.start();}}

继承Thread类(直接继承thread类，或者使用匿名嵌套类)

class SumThread extends Thread{
private long length;
public SumThread(long length,String name){
super(name);
this.length=length;
}
public void run(){
long temp=0;
for(int i=1;i<=length;i++){
try {
Thread.sleep((int)(Math.random()*10));
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
temp+=i;
}
System.out.println(Thread.currentThread()+"zonghe:"+temp);
}
}
public class Thread1 {
public static void main(String[] args) {
System.out.println("线程");
System.out.println(Thread.currentThread());
SumThread st1=new SumThread(150,"线程1");
st1.start();
new Thread("线程2"){
int length=150;
public void run(){
long temp=0;
for(int i=1;i<=length;i++){
try {
Thread.sleep((int)(Math.random()*10));
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
temp+=i;
}
System.out.println(Thread.currentThread()+"zonghe:"+temp);
}
}.start();
}}