/************************************************************************
 * Matt Kretchmar
 * March 22, 2006
 * ParameterTest.java
 * This program illustrates the difference between pass-by-value
 * and pass-by-reference.  Primitive types are always passed by value
 * while object types (including arrays) are always passed by 
 * reference.
 ***********************************************************************/
class ParameterTest
{
    public static void main ( String args[] )
    {
        int  x = 0;
        int  a[] = {0, 0, 0};
        
        System.out.println("Before method call, x = " + x );
        primativeParameter(x);
        System.out.println("After method call, x = " + x );
        
        System.out.println("Before method call, a[0] = " + a[0] );
        objectParameter(a);
        System.out.println("After method call, a[0] = " + a[0] );
    }
    /******************************************************************
     * primativeParameter
     * This method illustrates the pass-by-value concept of primative 
     * parameters.
     ******************************************************************/
    public static void primativeParameter ( int x )
    {
        // Changes to x are local only because this method keeps 
        // a separate local copy of x.  
        x = 3;
    }
    /******************************************************************
     * objectParameter
     * This method illustrates the pass-by-reference concept of object 
     * parameters.
     ******************************************************************/
    public static void objectParameter ( int array[] )
    {
        // Because the reference is passed in, changes to objects 
        // (including arrays) will affect the actual parameter passed in.
        array[0] = 1;
    }
}