String.charAt（）工作扫描器错误

Question

I have a problem when I'm using Scanner in my project. I have a file with string like that:

• Name = Jhon
• count = 100
• 1ip = 127.0.0.7
• end = file

All this string I'm adding in array and this array add in two ArrayList's. I don't need a line witch starts with a number. Like "1ip". So I try to skip it.

And that is my code of method:

    public void scan_file() throws IOException{
      Scanner sc = null;         
      String [] array_string;
      String not_sring;

      try{  
              File out = new File("file.txt");          
          sc = new Scanner(out);
          while(sc.hasNextLine()){
          not_sring=sc.nextLine();
           if(not_sring.charAt(0)>='0' && not_sring.charAt(0)<='9'){
                array_string = sc.nextLine().split("=");
            }
           else{
               array_string=sc.nextLine().split("=");
               for (int i=0; i<array_string.length; i++)
                for(int j=1; j<array_string.length; j++){
                           list_id.add(array_string[i]);
                           list_value.add(array_string[j]);     
                     }
               }
        }
      }

         catch(FileNotFoundException e) {
                 //e.printStackTrace(System.out);
                 System.out.println("File not found");
                 scan_file();
         } 
        sc.close();}

And that all isn't working. If someone has understood my english and my Task.

Answer 1

您在循环中两次调用nextLine() ，这当然是您的问题之一。

Answer 2

If you want to skip a line just continue to the next loop iteration with :

 if(not_sring.charAt(0)>='0' && not_sring.charAt(0)<='9'){
     continue; // This will skip to the next while iteration begining with the conditional check
 }

And if your format is id=value than use :

    array_string=not_sring.split("="); // No need to use nextLine again as it will overwrite the current line read into not_sring
    list_id.add(array_string[0]); 
    list_value.add(array_string[1]);

This is assuming the file format is correct as described. And there is no need for the else anymore between those blocks.

Answer 3

try{  
          File out = new File("file.txt");          
          sc = new Scanner(out);
          while(sc.hasNextLine()){
              not_sring=sc.nextLine();
              if(!Character.isDigit(not_sring.charAt(0))){
                array_string = not_sring.split("=");
                list_id.add(array_string[0]);
                list_value.add(array_string[1]);
              }
          }

}

Check this, you don't need for loops and you need one if block or otherwise the string will be discarded.