Both files run, you have to answers the following questions with the reason you

Question

Both files run, you have to answers the following questions with the reason you chose an answer:
o Integer variables are passed by ____________
o Integer arrays are passed by ____________
o String variables are passed by ____________ (You will need to research the String class
to explain how String objects are passed into methods!)
o Object variables are passed by ____________


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 + " hours = " + hours;
}
}

public class Assignment3_2
{
public static void main(String args[])
{ int int_test = 10;
int int_array[] = {100,200,300};
String str_test = "CIS150";
MyClass object_test = new MyClass("Maya", 15);

System.out.println(" int_test before method call..." + int_test);
test_passing_int(int_test);
System.out.println("int_test after method call..." + int_test);

print_array(int_array, " int_array before method call..");
test_passing_array(int_array);
print_array(int_array, "int_array after method call..");
test_passing_array(int_array);

System.out.println(" str_test before method call..." + str_test);
test_passing_String(str_test);
System.out.println("str_test after method call..." + str_test);

System.out.println(" object_test before method call..." + object_test.toString());
test_passing_object(object_test);
System.out.println("object_test after method call..." + 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] + " ");

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 = "CIS250";
}
public static void test_passing_object(MyClass _obj)
{ _obj.setNameHours("Pam", 16);
}
}

Explanation / Answer

o Integer variables are passed by Pass-By-Value, so just a copy is given to the method (because ints are a primitive type) and the original value remains unchanged. This is evidenced by int_test. o Integer arrays are passed by Pass-By-Reference (because an array is just a group of addresses, the address of array[0] is passed), so a method is editing the actual array. This is evidenced by int_array. o String variables are passed by Pass-By-Reference (because an actual String object is created for every String), BUT String objects are immutable, so the method does not change the actual String (as seen in str_test). o Object variables are passed by Pass-By-Reference, so the address of the object is passed and the method is editing the real object (as seen in object_test).

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