Null is casted in decompiled java class file

Question

I decompiled one of my java .class files and saw this line of code

new ResponseModel("Reset Complete", false, (LinkedHashMap)null)

The line corresponds to

new ResponseModel("Reset Complete", false, null);

Why was the null parameter casted? Is it just my decompiler hinting the parameter type?

Possible duplicate of [No Exception while type casting with a null in java](https://stackoverflow.com/questions/18723596/no-exception-while-type-casting-with-a-null-in-java) — Kaustubh Khare, Sep 03 '18 at 09:29

score 3 · Accepted Answer · answered Sep 03 '18 at 09:32

Immagine you've overloaded a method:

public class Foo {

    public void something (String s) { ... }
    public void something (List l) { ... }
}

Invoking something with a null argument is now ambiguous. To bind the invocation to either method, you need to cast the null value, giving it a type:

new Foo().something((String)null);
new Foo().something((List)null);

As this class may be different at runtime than on compile time (on compile time, the method may not be overloaded, but on runtime the class is a newer version which has an overloaded method), the compiler makes it explicit in the bytecode to prevent ambiguousness later.

Null is casted in decompiled java class file

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