java计算机二级

import java.io.*;

public class Java_3
{
   public static void main(String[] args)
   {
      Java_3 exceptionExample = new Java_3();
     //*********Found**********
      try
      {
         FileInputStream fi = new FileInputStream("C:" + "\\" + "abc.txt");
      }
  //*********Found**********
      catch(FileNotFoundException ex)
      {
  //*********Found**********
         System.out.println(ex.getMessage()+
         "请确认文件路径及文件名是否正确！");
      }
   }
}

import java.io.*;
import java.util.Vector;

public class Java_2{
   public static void main(String s[]){
      Vector v=new Vector();
      try{
         //*********Found**********
         BufferedReader in = new BufferedReader(new InputStreamReader(System.in));    //键盘输入
         String str = "";
         System.out.println("请输入用户和密码信息，中间用空格隔开，输入quit退出:");
         while (!(str.equals("quit")||str.equals("QUIT"))){
            str = in.readLine();
            //*********Found**********
            if(isValid(str))      //验证输入是否有空格
               v.add(str);
            else{
               if(!(str.equals("quit")||str.equals("QUIT")))
                  System.out.println("The string is NOT valid!");
            }
         }
	        
         System.out.println("请输入保存到的文件名:");
         //*********Found**********
         str=in.readLine();

         String curDir = System.getProperty("user.dir");
         File savedfile=new File(curDir+"\\"+str);
            
         //*********Found**********
         BufferedWriter out = new BufferedWriter(new FileWriter(savedfile));
         for(int i=0; i<v.size(); i++){
            String tmp=(String)v.elementAt(i);
            out.write(tmp);
            //*********Found**********
            out.write("\n");      //换行
         }
         out.close();
        
      }
      //*********Found**********
      catch(Exception e){
         System.out.print("ERROR:"+e.getMessage());	
      }
   }
   /**
   * 判定输入的字符串是否符合规范
   * @param  s  输入的待校验的字符串
   * @return    校验的结果，正确则返回为真
   */
   public static boolean isValid(String s){
      if(s.indexOf(" ")>0) return true;
      else return false;
   }
}

import java.io.*;
import java.lang.Thread;


class MyThread extends Thread{
   public int x = 0;
//*********Found********
   public void run(){
    System.out.println(++x);
  }
}
//*********Found********
class RThread implements Runnable{
   private int x = 0;
   public void run(){
        System.out.println(++x);
  }
}

public class Java_3 {
  public static void main(String[] args) throws Exception{
    for(int i=0;i<5;i++){
       Thread t = new MyThread();
	//*********Found********
       t.start();
    }
    Thread.sleep(1000);
    System.out.println();
//*********Found********
    RThread r = new RThread();
//*********Found********
    for(int i=0;i<5;i++){
       Thread t = new Thread(r);
       t.start();
    }
  }
}

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;

public class Java_3
{
   public static void main(String[] args)
   {
      ExceptTestFrame frame = new ExceptTestFrame();
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      frame.setVisible(true);
   }
}

class ExceptTestFrame extends JFrame
{
   public ExceptTestFrame()
   {
      setTitle("ExceptTest");
      Container contentPane = getContentPane();
      ExceptTestPanel panel = new ExceptTestPanel();
 //*********Found********
      contentPane.add(panel);
      pack();
   }
}

class ExceptTestPanel extends Box
{
   public ExceptTestPanel()
   {
      super(BoxLayout.Y_AXIS);
      group = new ButtonGroup();
      addRadioButton("整数被零除", new
         ActionListener()
         {
     //*********Found********
            public void actionPerformed(ActionEvent event)
            {
               a[1] = 1 / (a.length - a.length);
            }
         });
      textField = new JTextField(30);
      add(textField);
   }

  //*********Found********
   private void addRadioButton(String s, ActionListener listener)
   {
      JRadioButton button = new JRadioButton(s, false)
         {
            protected void fireActionPerformed(ActionEvent event)
            {
               try
               {
                  textField.setText("No exception");
                  super.fireActionPerformed(event);
               }
               catch (Exception exception)
               {
     //*********Found********
                  textField.setText(exception.toString());
               }
            }
         };
      button.addActionListener(listener);
      add(button);
      group.add(button);
   }
   private ButtonGroup group;
   private JTextField textField;
   private double[] a = new double[10];
}

import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

public class Java_2
{
   public static void main(String args[])
   {
      if(args.length<2)
      {
         System.out.println("ERROR: need parameters.");    
         System.out.println("\n -usage: java <classname> <file1> <file2>");    
         System.exit(0);
      }
      File f1=new File(args[0]);
      //*********Found**********
      File f2=new File(args[1]);
      try
      {
         //*********Found**********
         FileReader fr=new FileReader(f2);
         FileWriter fw=new FileWriter(f1,true);
         int b;
         //*********Found**********
         while(( b=fr.read() ) != -1 )  fw.write(b);
         fr.close();
         fw.close();
      }
      catch(IOException e)
      {
         e.printStackTrace();
      }
      System.out.println("has done!");
      //*********Found**********
      if(f2.delete()) System.out.print("SUCCESS!");
   }
}

public  class  Java_2
{    
   public static void main(String[] args)
   {
      Thread t = new SimpleThread("Testing_Thread");
       //*********Found**********
      t.start()  ;   
   }
} 
 //*********Found**********
class SimpleThread extends Thread 
{
   public SimpleThread(String str)
   {
      //*********Found**********
      super(str)   ;
   }
    //*********Found**********
   public void run()
   {  
      System.out.println("Running the " + getName() + ":");
      for (int i = 0; i < 5; i++)
      {
         System.out.println("---" + i + "---" + getName());
         try
         {
            sleep((int)(2 * 100));
         }
         //*********Found**********
         catch(InterruptedException e) { }
      }
   }
}