Java通过IO流输入输出 向文件中存入大量三个属性的值，并通过验证前两个属性输出第三个属性

package ABC1;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Random;

public class Filetest {

    public static void main(String[] args) {
        // TODO 自动生成的方法存根
        
        try {
            File file =new File("D:/textFile.txt");
            if(!file.exists())
            {
                file.createNewFile();
            }
            FileWriter out = new FileWriter(file); 
            //往文件写入
            out.write("userid\tpassword\tusername"+"\r\n");
            //换行
            out.write("23213\t66yy\t解饿"+"\r\n");
            for(int j=0;j<100000;j++){
            int userid = randomInt();
            int password = randomInt();
            int username = randomInt();
            out.write(userid+"\t"+password+"\t"+username+"\r\n");
            }
            out.write("2321sdf3\t6fgds6yy\t好就是解饿"+"\r\n");
            //刷新IO内存流
            out.flush();
            out.close();
            //关闭
            String temp=null;
            int i =1;
            BufferedReader in=new BufferedReader(new FileReader(file));
            String rtn ="userid不正确" ;
            while((temp=in.readLine())!=null)
            {
                
                if(temp.indexOf("451080121")!=-1)
                {
                    
                
                    String[] check = temp.split("\t");
                
                
                    if(check[1].equals("805786460"))
                    {
                        rtn="username="+check[2];                        
                    }
                    else
                    {
                        rtn="密码错误";
                        //System.out.println("密码错误");
                    }
                }
            }
            System.out.println(rtn);
            
        } catch (IOException e) {
            // TODO 自动生成的 catch 块
            e.printStackTrace();
        }
    }
    
public static int randomInt()
{
    int rtn =0;
    Random random = new Random();
    rtn=random.nextInt(999999999)+10000;
    return rtn;
}
}