I am writing a program in java for the Shortest Job First Scheduling , have generate the Process ID and Process Time separately but i have to put both in an array and would like someone to help me please.

If both Process ID and Process Time have a common subset of operations that you can use from the array then you can have them as derived classes:

abstract class process_thingie {
  public abstract String get_thingie();
}

class process_id extends process_thingie {
  private String id;
  
  public process_id ( String init ) {
    id = new String ( init );
  }
  
  public String get_thingie() {
    return id;
  }
  
  // ID specific stuff
}

class process_time extends process_thingie {
  private String time;
  
  public process_time ( String init ) {
    time = new String ( init );
  }
  
  public String get_thingie() {
    return time;
  }
  
  // Time specific stuff
}

public class Main {
  public static void main ( String[] args ) {
    process_thingie[] list = new process_thingie[10];
    
    for ( int i = 0; i < 5; i++ )
      list[i] = new process_id ( "id: " + i );
    for ( int i = 5; i < 10; i++ )
      list[i] = new process_time ( "time: " + i );
    
    for ( int i = 0; i < 10; i++ ) {
      if ( i % 5 == 0 )
        System.out.println();
      System.out.print ( list[i].get_thingie() + "\t" );
    }
  }
}

Provided you only use the common subset of methods from the array items then you can let polymorphism do the dirty work for you.

Thanks Narue you save me ...