What function of the Java Boolean class makes it act as a boolean in an if statement or expression

Question

I presume if I write:

Boolean doIt; 
...
if (doIt) { doSomething();}

There is some function in the Boolean class that gets called that returns a boolean that the if statement evaluates to decide to doSomething() or not. What is the name of that function so I can write a class like:

public class MagicBoolean {

    public boolean toBoolean() { // this is the function name I am looking for
       return true;
    }
...
MagicBoolean doIt;
...
if (doIt) { doSomething(); } // doIt.toBoolean() is implicitly called here

and get the same effect. And, no I don't want to extend Boolean as the logic in toBoolean will be much more complex than checking a simple value and it may involve computation or it may be a memo-ized value, but I don't want the uses of that "value" to know or care. It's just a flag to tell them that the strategy being used wants them to do this (or that) at this particular time.

This is called [auto(un)boxing](https://docs.oracle.com/javase/specs/jls/se8/html/jls-5.html#jls-5.1.8). And your own classes cannot do it. Not without custom code generation/replacement. — Boris the Spider, Nov 09 '20 at 20:20
So, there is no equivalent of operator boolean() like in C++. — intel_chris, Nov 09 '20 at 20:24
So I presume I need to write something like: ``` if (a.get()) { doSomething(); } ``` — intel_chris, Nov 09 '20 at 20:26
I think you need to think a bit more OO and a bit less procedurally. For example `a.ifSomething(this::doSomething)`. — Boris the Spider, Nov 09 '20 at 20:29
Basically closely to how [Optional.ifPresent()](https://stackoverflow.com/questions/24228279/proper-usage-of-optional-ifpresent) works. — Kayaman, Nov 09 '20 at 20:31
Note that Groovy _does_ have this capability; the name of the "magic method" is `asBoolean()`. — chrylis -cautiouslyoptimistic-, Nov 09 '20 at 20:42

What function of the Java Boolean class makes it act as a boolean in an if statement or expression

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