Call overloaded constructors using reflection

Example: Invoke different constructors by passing relevant parameters

import java.lang.reflect.*;

class NewInstanceWithReflection{
    public NewInstanceWithReflection(){
        System.out.println("Default constructor");
    }
    public NewInstanceWithReflection( String a){
        System.out.println("Constructor :String => "+a);
    }
    public static void main(String args[]) throws Exception {
        
        NewInstanceWithReflection object = (NewInstanceWithReflection)Class.forName("NewInstanceWithReflection").newInstance();
        Constructor constructor = NewInstanceWithReflection.class.getDeclaredConstructor( new Class[] {String.class});
        NewInstanceWithReflection object1 = (NewInstanceWithReflection)constructor.newInstance(new Object[]{"StackOverFlow"});
        
    }
}

output:

Default constructor
Constructor :String => StackOverFlow

Explanation:

Create instance of class using Class.forName : It calls default constructor
Invoke getDeclaredConstructor of the class by passing type of parameters as Class array
After getting the constructor, create newInstance by passing parameter value as Object array

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