'void' in Java

All methods in Java must be one return type. void tell's to the JVM that that specific method will not return anything.
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What does void do in java?

 In Java, the constructor is not a method. It only has the name of the class and a specific visibility. If it declares that returns something, then it is not a constructor, not even if it declares that returns a void. Note the difference here:

public class SomeClass {
    public SomeClass() {
        //constructor
    }
    public void SomeClass() {
        //a method, NOT a constructor
    }
}

Also, if a class doesn't define a constructor, then the compiler will automatically add a default constructor for you.

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java “void” and “non void” constructor