Sun Codemodel generic method invocation

Question

I'm using Codemodel library for java-class generation. Is there a way to generate a generic method invocation which looks like this:

clazz.<String>get(value)

There is certainly a way of just casting a return result to a correct type using the following expression:

JExpr.cast(stringType, clazz.invoke("get").arg(value))

which results in

(String) clazz.get(value)

but the preferred way of casting is the first one, as this code is generating templates for further manual editing by developers.

score 1 · Accepted Answer · answered Sep 19 '16 at 19:09

With the existing JCodeModel API, there is no pre-built way to handle this. You can, however, define your own JStatement type to generate the generic declaration like this:

    JDefinedClass definedClass = codeModel._class(JMod.PUBLIC, "org.test.Tester", ClassType.CLASS);

    JMethod method = definedClass.method(JMod.PUBLIC, codeModel.VOID, "test");

    final JType targetType = codeModel.ref(String.class);
    final JVar clazzVar = method.body().decl(codeModel.ref(Class.class), "clazz", JExpr.invoke("getClass"));

    method.body().add(new JStatement(){
        @Override
        public void state(JFormatter f) {
            f.g(clazzVar).p(".<").g(targetType).p(">").p("get").p("();").nl();
        }
    });

Which generates:

package org.test;

public class Tester {

    public void test() {
        Class clazz = getClass();
        clazz.<String >get();
    }
}

This is by no mean a complete solution (It's missing method call arguments for instance). Take a look at the implementation of the generate() method in JInvocation for the details that are required.

That's exactly what I need. Thanks, John! – Dmitry Smorzhok Sep 20 '16 at 05:17 — Dmitry Smorzhok, Sep 20 '16 at 05:17

Sun Codemodel generic method invocation

1 Answers1