entities are passed by value or passed by reference

**syntrax** · 12-17-2009, 02:38 AM

Are these past by "Value" or "Reference"?

Integer variables are passed by:
Value
Integer arrays are passed by:
Value
String variables are passed by:
Value
Object variables are passed by:
Value

i'm saying that they are passed by Value, right?

ps.
i know the code seems wierd or coded like a wth,,, but it was provided by my instructor. I'm guessing trying to make things tricky?

Java Code:

/**
 * @author Carlos Saavedra
 * @version 8.1.5 2009/12/15
 */

public class Assignment8_B 
{
    public static void main(String[] args) 
    {
        int int_test = 10;
        int int_array[] = {100, 200, 300};
        String str_test = "CIS 150";
        MyClass object_test = new MyClass("Carlos", 15);
        
        System.out.println("int_test BEFORE method call...\t\t" + int_test);
        test_passing_int(int_test);
        System.out.println("int_test AFTER method call...\t\t" + int_test);
        
        print_array(int_array, "Int_array BEFORE  method call...\t");
        test_passing_array(int_array);
        print_array(int_array, "int_array AFTER method call.....\t");
        test_passing_array(int_array);
        
        System.out.println("str_test BEFORE method call...\t\t" + str_test);
        test_passing_String(str_test);
        System.out.println("str_test AFTER method call...\t\t" + str_test);
        
        System.out.println("object_test BEFORE method call...\t" + object_test.toString());
        test_passing_object(object_test);
        System.out.println("object_test AFTER method call...\t" + object_test.toString());
    }
    
    public static void test_passing_int(int _i)
    {
    	_i *= 2;
    }
    
    public static void print_array(int _arr[], String msg)
    {
    	System.out.print(msg);
    	for(int i=0; i<_arr.length; i++)
    		System.out.print(_arr[i] + "\t");
    	
    	System.out.println();
    }
    
    public static void test_passing_array(int _arr[])
    {
    	for(int i=0; i < _arr.length; i++)
    		_arr[i] *= 2;
    }
    
    public static void test_passing_String(String _str)
    {
    	_str = "CIS150";
    }
    
    public static void test_passing_object(MyClass _obj)
    {
    	_obj.setNameHours("Pam\t", 16);
    }
}

MyClass:

Java Code:

public class MyClass
{
	String name;
	int hours;
	
	public MyClass(String _name, int _hours)
	{
		name = _name;
		hours = _hours;
	}
	
	public void setNameHours(String _name, int _hours)
	{
		name = _name;
		hours = _hours;
	}
	
	public String toString()
	{
		return "Name: " + name + "\tHours: " + hours;
	}
}