Extending a class and wrapping methods

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You can extend any class from .NET Framework DLL by extending the Java class with the NObject/JObject type and then call the constructor base constructor by passing the name of the called type and arguments for its constructor as an argument.

Assuming we have a custom .NET Framework DLL with the following class inside:

using System;

namespace TestNamespace
{
	public class TestClass
	{
		public TestClass() { }
		~TestClass()
		{
			Console.WriteLine("Displaying object from .NET destructor message");
		}
		public static int MyStaticField { get; set; }
		public int MyInstanceField { get; set; }

		public static string SayHello(string name)
		{
			return "Hello " + name;
		}

		public int MultiplyByTwo(int arg)
		{
			return arg * 2;
		}

		public T MyGenericMethod<T>(T arg1)
		{
			return arg1;
		}
		public K MyGenericMethodWithTwoTypes<T, K>(T arg1)
		{
			return default(K);
		}

		public void MethodWithRefArg(ref int arg)
		{
			arg = arg + 44;
		}

		public string PassTypeArg(Type myType)
		{
			return myType.ToString();
		}

		public string MethodWithEnumArg(SampleEnum value)
		{
			return value.ToString();
		}
	}
}

To extend this class and wrap method from this class create the following class:

I code in:
package utils;

import com.javonet.JavonetException;
import com.javonet.api.NObject;

public class ExtendedTestClass extends NObject {

    public ExtendedTestClass() throws JavonetException
    {
        super("TestNamespace.TestClass");
    }

    public int MultiplyByTwo(int arg) throws JavonetException
    {
        return this.invoke("MultiplyByTwo", arg);
    }
}

And use it like any other Java class

I code in:
// Todo: activate Javonet and add reference to .NET library

// create extended class instance
ExtendedTestClass myExtendedTestClass = new ExtendedTestClass();

// use method from this class
Integer response = myExtendedTestClass.MultiplyByTwo(77);

// write response to console
System.out.println(response);

See Live Example!

Additional references