Array problem

In the main I have a Array, how can i use the data from this array in a sub

Do you mean somthing like this?

Code:

---

    class ArrayExample{
      public static void main(String[] args){

      String[] s = {"Hello","Whats's","up?"};
      printStrings(s);
     
     
      }
      static void printStrings(String[] s){
        for(int i = 0; i < s.length; ++i){
          System.out.println(s[i]);
        }
      }
  }

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Some things that i would like to point out. Java is a pass by value language. Not a pass by refrence. First let me explain pass by refrence. When a variable is passed to a method a copy of that variable is passed. If the method modifies it's parameters those modifications are visible when the method returns.

Java does not do this. It is a pass by value language. For instance. The following code illustrates this point.

Code:

---

class Example{
      public static void main(String[] args){

      int i = 10;
      printInt(i);
      System.out.println(i);  // prints 10
             
      }
      static void printInt(int i){
          System.out.println(i); // prints 10
          i = 25;
         
      }
  }

---

However when a refrence type is involved, the valus is passed by refrence. This is not the same as "pass-by-refrence". If java were a pass by refrence language, when a refrence type was passed to a method, it would be passed as a refrence to the refrence.

If you notice in this block of code. When an array is passed to a method. It's contents are modified when the method returns.

Code:

---

class ArrayExample{
      public static void main(String[] args){

      String[] s = {"Hello","Whats's","up?"};
      printStrings(s);
      for(int i = 0; i < s.length; ++i){       
          System.out.println(s[i]);
        }
     
      }
      static void printStrings(String[] s){
        for(int i = 0; i < s.length; ++i){       
          System.out.println(s[i]);
        }
        s[2] = "down";
      }
  }

---

Heres another example. Even though we are modifying the contents of the variable i and returning that value from the method the contents of the variable were never changed.

Code:

---

    class Example{
      public static void main(String[] args){

      int i = 10;
      int k = 0; 
      k = printInt(i);
      System.out.println(k);  // prints 10
             
      }
      static int printInt(int i){
          System.out.println(i); // prints 10
          i = 25;
          return i;
      }
  }

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