Calling generic methods

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With Javonet you can very easily invoke any generic instance or static method. To call a generic method, you need to provide types that will be used during the method invocation. Those types can be passed as an instance of NType objects initialized with particular .NET types.

Assuming we have a custom JAR library with the following class inside:

public class TestClass {
    public TestClass() {
    }

    public static int MyStaticField;

    public int MyInstanceField;

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

    public static int MethodExpectingPrimitiveInt(int arg) {
        return arg * 2;
    }

    public static int MethodExpectingClassInteger(Integer arg) {
        return arg * 2;
    }

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

    public <T> T MyGenericMethod(T arg1)
    {
        return arg1;
    }
}

To use generic methods from this class:

I code in:

This snippet doesn't support selected combination of technologies.

  • Create an instance of our GenericSample class.
  • Using the generic method, initialize the generic method invocation by passing one or many generic types of arguments.
  • Invoke your method with a sample argument.

Javonet.getType(typeName) returns an instance of NType object attached to a specific .NET type. The instruction NType myType = Javonet.getType("String") is the Java equivalent of the .NET Type myType = typeof(String).

See Live Example!

Additional references