This example finds the positive integers from the given array and store these positive integers in another array.

import java.util.*;

public class positive {

public static void main(String[] args) {
int a[]={-1,2,3,4,-5};
retainPositiveNumbers(a);
}
public static void retainPositiveNumbers(int[] a) {
    List<Integer> list=new ArrayList<Integer>();
    for(int i=0; i<a.length;i++){
        if(a[i]>0){
         list.add(new Integer(a[i]));
        }
    }
    int[] c = new int[list.size()];
    for (int i=0; i < c.length; i++){
        c[i] = list.get(i).intValue();
    }
     for (int i=0; i < c.length; i++){
     System.out.println(c[i]);
    }
  }
}