Java1-武恺莉1407094208

[kailiwu]

1.删除后三只羊
        //第一种方法
        int count=sheeplist.size();
        for(int i=count-1;i>=count-3;i--){
            sheeplist.remove(i);
        }
        //第二种方法
        for(int i=sheeplist.size()-3;i<sheeplist.size();){
            sheeplist.remove(i);
        }
        //第三种方法
        int count1=0;
        while(count1<3){
            sheeplist.remove(sheeplist.size()-1);
            count++;
        }
        //第四种方法
        int count2=sheeplist.size();
        for(int i=0;i<sheeplist.size();i++){
            while(i==count2-3){
                sheeplist.remove(i);
                i=i-1;
            }
        }
2.自动写文件
for(int i=0;i<10;i++){
        File filei=new File(files, "helloworld"+i+".txt");
        try {
            OutputStream os=new FileOutputStream(filei);
            String s="我真";
            s=s+i;
            os.write(s.getBytes());
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
3.线程实现方法继承Thread与接口Runnnale的区别
(1)继承自Thread
        ThreadExtend t1=new ThreadExtend("窗口一");
        ThreadExtend t2=new ThreadExtend("窗口二");
        ThreadExtend t3=new ThreadExtend("窗口三");
        t1.start();
        t2.start();
        t3.start();
class ThreadExtend extends Thread{
    private int tickets=5;
    public ThreadExtend(String name) {
        super(name);
    }
    @Override
    public void run() {
        while(this.tickets>0){
            this.tickets--;
        System.out.println("票在"+this.getName()+"被卖出");
        }
    }
}
(2)Runnable接口
        ThreadExtend t=new ThreadExtend();
        Thread c1=new Thread(t,"Runnable1");
        Thread c2=new Thread(t,"Runnable2");
        Thread c3=new Thread(t,"Runnable3");
        c1.start();
        c2.start();
        c3.start();
class ThreadExtend implements Runnable{
    private int ticket=5;
    @Override
    public void run() {
        while(this.ticket>0){
            this.ticket--;
        System.out.println("票在"+Thread.currentThread().getName()+"被卖出");
        }
        }

}
继承自Thread只能是单继承，每个线程之间是独立的；Runnnale接口可以实现线程间的资源共享。