Java1-汤世征1407084235

[tago-tech]

1.删羊

//删除羊的三种办法
//1 顺序递增删羊
int k=sheepList.size();
  for(int i=k-3;i<k;i++)
     {
       sheepList.remove(k-3);
      }
//2  顺序递减删羊
int k=sheepList.size();
  for(int i=k-1;i>=k-3;i--)
     {
       sheepList.remove(i);
      }
//3  从后向前删
  for(int i=0;i<3;i++)
   {
        sheepList.remove(sheepList.size()-1);
    }

2.IO文件

package javahomework;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;

public class  doing2 {
public static void main(String[] args) {
    File manyfile=new File("D://testfoio");
    File file = null ;
    try {
    if(!manyfile.exists())
    manyfile.mkdir();
    for(int i=0;i<10;i++)
    {file=new File(manyfile.getAbsolutePath(),"helloworld"+i+".txt");
    if(!file.exists())
    file.createNewFile();}
    } catch (IOException e) {
    e.printStackTrace();
    }
    String []filenames= manyfile.list();
    for(int i=0;i<filenames.length;i++)
    System.out.println(filenames[i]); 
    File file_3=new File(manyfile,"helloworld_3.txt");
    file_3.delete();
    for(int i=0;i<=9;i++)
   {
     file =new File(manyfile,"helloworld"+i+".txt");
     OutputStream os=null;
     try {
     os=new FileOutputStream(file);
      String s="我真"+i;
     try {
      os.write(s.getBytes());
      } catch (NumberFormatException | IOException e) {
       e.printStackTrace();
      }
       } catch (FileException e) {
      e.printStackTrace();
      }finally
      {
      try {
       os.close();
      } catch (IOException e) {
      e.printStackTrace();
      }}
}
}
}

比较Thread和Runnable

class othread extends Thread{
public othread(String name){
    super(name);
}
public othread(){
    super();
}
public void run() {
    for(int i=0;i<5;i++){
        System.out.println("othread"+this.getName()+i);
    }
}

}

class threadexp implements Runnable{

    public String name;

    public String getName() {
    return name;
    }
    public void setName(String name) {
    this.name = name;
    }


@Override
public void run() {
    // TODO Auto-generated method stub
    for(int i=0;i<5;i++){
        System.out.println("runable"+this.getName()+i);
    }

}
}

[hipoom]

类名首字母记得大写.