Picture of the Action

It looks as if there is a contradiction here:

• In the previous example, the method COULD NOT change the int variable in main().
• In this example, the method CAN change the int array in main().

There is actually no contradiction here. Remember that an array is an object. When an object is a parameter, the called method gets a reference to the object. That is, it gets a way to find the object in memory, but no new object is created. In the example, the called method gets a reference to the array object. There is only one array, so any changes will affect that array. The picture shows this.

When the method call cng.zeroElt( value, 0 ) is executed, the parameter x of the method gets the value of the of the variable, which is a reference to the array.