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Thread: My code return null, Why?

  1. #1
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    Default My code return null, Why?

    In the Main class I have the following
    public class test {
     
        public static void main(String args[]){
     
     
     
            String separ;
            String lin = "/";
            String wind = "\\";
     
            String s = System.getProperty("file.separator");
            if (s != wind) 
              FileSeparatorExample.separator = lin;
     
            else 
                FileSeparatorExample.separator=wind;
     
          System.out.println(FileSeparatorExample.a);
    }
     
    }

    in the another class
    public class FileSeparatorExample {
     
     
        /**
         * @param args the command line arguments
         */
     
      public static String separator;
      public static String a ;
     
      public FileSeparatorExample(){
          this.a = FileSeparatorExample.separator;
      }  
     
      public static void lodA(){
          a = separator;
          return  ;
      }
     
     }

    Why System.out.println(FileSeparatorExample.a);
    return me "null"
    how to fix?
    I am a new in java, please help me!!!

    Thanks


  2. #2
    Crazy Cat Lady KevinWorkman's Avatar
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    Default Re: My code return null, Why?

    Do you understand how the static keyword works? Do you understand how constructors are called?

    Why are separator and a static? When do you set separator? When do you set a?
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