Calling overloaded method passing null argument

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In some cases you might need to call a method - that has multiple overloads with the same number of arguments - passing null. Considering following case:

I want to use:

.NET Framework DLL

namespace TestClass
{
	public class TestClass
	{
		public TestClass() { }

		using System;
		
		namespace TestNamespace
		{
			public class TestClass2
			{
				public string MethodA(String arg)
				{
					return "Method with String argument called";
				}
				public string MethodA(Object arg)
				{
					return "Method with Object argument called";
				}
				public string MethodA(int? arg)
				{
					return "Method with nullable int argument called";
				}
			}
		}
		
	}
}
using System;

namespace TestNamespace
{
	public class TestClass2
	{
		public string MethodA(String arg)
		{
			return "Method with String argument called";
		}
		public string MethodA(Object arg)
		{
			return "Method with Object argument called";
		}
		public string MethodA(int? arg)
		{
			return "Method with nullable int argument called";
		}
	}
}

If you call MethodA passing "null" as argument .NET side will not be able to resolve which method should be called as in both overloads null can be passed. Ambigous invocation exception will be thrown. To overcome this issue Javonet introduces "NNull" type which allows to pass type-specific null value.

How to call .NET method passing type-specific null value:

I code in:

Java

I want to use:

.NET Framework DLL

import com.javonet.sdk.*;

public class SampleProgram {

    private static final String resourcesDirectory = ".";
    public static void main(String []args) {

        // Todo: activate Javonet and add reference to .NET library
        
        // create instance
        NObject sampleObject = Javonet.New("TestNamespace.TestClass2");
        
        // call MethodA with String argument passing null
        String response = sampleObject.invoke("MethodA", new NNull("String"));
        
        // call MethodA with generic int? argument
        String response2 = sampleObject.invoke("MethodA", new NNull("System.Nullable`[System.Int32]"));
        
        // write response to console
        System.out.println(response);
        System.out.println(response2);
        // expected output:
        // System.String
     }
}// Todo: activate Javonet and add reference to .NET library

// create instance
NObject sampleObject = Javonet.New("TestNamespace.TestClass2");

// call MethodA with String argument passing null
String response = sampleObject.invoke("MethodA", new NNull("String"));

// call MethodA with generic int? argument
String response2 = sampleObject.invoke("MethodA", new NNull("System.Nullable`[System.Int32]"));

// write response to console
System.out.println(response);
System.out.println(response2);
// expected output:
// System.String

See Live Example!

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Calling overloaded method passing null argument

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