Understanding Java Arrays -

please @ following code :

public static void main(string[] args) {     random random = new random();     int[] array = new int[10];     arrays.setall(array, operand -> random.nextint(10));     system.out.println(arrays.tostring(array));     swap(array, 0, 9);     system.out.println(arrays.tostring(array)); }  static void swap(int[] array, int i, int j) {     int temp = array[i]; // pass value ??     array[i] = array[j]; // value of temp doesn't change, why?     array[j] = temp; // temp == array[i] } 

what happens in method swap?

i need full explanation , low level.

edit :

ok, let me show example :

public class stringholder {      private string value;      public stringholder(string value) {         this.value = value;     }      public string getvalue() {         return value;     }      public void setvalue(string value) {         this.value = value;     }      @override     public string tostring() {         return getvalue();     }  } 

main method :

public static void main(string[] args) {     stringholder[] holders = new stringholder[]{new stringholder("string 1")};     stringholder tmp = holders[0];     holders[0].setvalue("string 2");     system.out.println(tmp);     system.out.println(holders[0]); } 

output :

string 2 string 2 

according @chokdee's answer, tmp new variable , have it's own piece of memory...

but when apply changes original variable (holder[0]), affects tmp.

another example :

public static void main(string[] args) {     stringholder[] holders = new stringholder[]{new stringholder("string 1")};     stringholder tmp = holders[0];     holders[0] = new stringholder("string 2");     system.out.println(tmp);     system.out.println(holders[0]); } 

output :

string 1 string 2 

thanks in advance.

i'll answer edit question.

public static void main(string[] args) {     stringholder[] holders = new stringholder[]{new stringholder("string 1")};     stringholder tmp = holders[0];     holders[0].setvalue("string 2");     system.out.println(tmp); // string 2     system.out.println(holders[0]); // string 2 } 

because both holding reference same object.

---

public static void main(string[] args) {     stringholder[] holders = new stringholder[]{new stringholder("string 1")};     stringholder tmp = holders[0];     holders[0] = new stringholder("string 2");     system.out.println(tmp); // string 1     system.out.println(holders[0]); // string 2 } 

in case reference hold tmp. after assign new stringholder object holders[0] reference in tmp turned actual object. normally, if did not have tmp garbage collector remove object. in end have two different stringholder objects.