Other languages use pass-by-reference or pass-by-pointer. But in Java no matter what type of argument you pass the corresponding parameter (primitive variable or object reference) will get a copy of that data, which is exactly how pass-by-value (i.e. copy-by-value) works.
In Java, if a calling method passes a reference of an object as an argument to the called method then the passed-in reference gets copied first and then passed to the called method. Both the original reference that was passed-in and the copied reference will be pointing to the same object. So no matter which reference you use, you will be always modifying the same original object, which is how the pass-by-reference works as well.
If call involves inter-process (e.g. between two JVMs) communication, then the reference of the calling method has a different address space to the called method sitting in a separate process (i.e. separate JVM). Hence inter-process communication involves calling method passing objects as arguments to called method by-value in a serialized form, which can adversely affect performance due to marshalling and unmarshalling cost.
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In Java, if a calling method passes a reference of an object as an argument to the called method then the passed-in reference gets copied first and then passed to the called method. Both the original reference that was passed-in and the copied reference will be pointing to the same object. So no matter which reference you use, you will be always modifying the same original object, which is how the pass-by-reference works as well.
If call involves inter-process (e.g. between two JVMs) communication, then the reference of the calling method has a different address space to the called method sitting in a separate process (i.e. separate JVM). Hence inter-process communication involves calling method passing objects as arguments to called method by-value in a serialized form, which can adversely affect performance due to marshalling and unmarshalling cost.
P.S: If image is not visible, open this in new window.
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