Creating Proxy from Interface with Setter Method with a Primative Parameter Doesn't Work

[saden1]

I am trying to create a proxy class that delegates all method invocation to an existing InvocationHandler implementation without success. The issue seems to stem from having a setter method that has a primitive parameter in my implemented interface (ProxyedInterface). With the bellow test case I get the following exception:

java.lang.VerifyError: Bad type on operand stack
Exception Details:
  Location:
    test/ProxyedInterface_Proxy_T3rJCc0Y.setPrimitive(JLjava/lang/String;)V @33: aastore
  Reason:
    Type long_2nd (current frame, stack[7]) is not assignable to 'java/lang/Object'
  Current Frame:
    bci: @33
    flags: { }
    locals: { 'test/ProxyedInterface_Proxy_T3rJCc0Y', long, long_2nd, 'java/lang/String' }
    stack: { 'java/lang/reflect/InvocationHandler', 'test/ProxyedInterface_Proxy_T3rJCc0Y', 'java/lang/reflect/Method', '[Ljava/lang/Object;', '[Ljava/lang/Object;', integer, long, long_2nd }
  Bytecode:
    0x0000000: b200 102a 1206 1222 05bd 0013 5903 b200
    0x0000010: 2653 5904 1229 53b6 0019 05bd 0004 5903
    0x0000020: 1f53 5904 2d53 b900 1f04 0057 b1       
    at java.lang.Class.getDeclaredFields0(Native Method)
    at java.lang.Class.privateGetDeclaredFields(Class.java:2575)
    at java.lang.Class.getDeclaredField(Class.java:2060)
    at net.bytebuddy.instrumentation.LoadedTypeInitializer$ForStaticField.onLoad(LoadedTypeInitializer.java:119)
    at net.bytebuddy.instrumentation.LoadedTypeInitializer$Compound.onLoad(LoadedTypeInitializer.java:195)
    at net.bytebuddy.dynamic.DynamicType$Default$Unloaded.initialize(DynamicType.java:2519)
    at net.bytebuddy.dynamic.DynamicType$Default$Unloaded.load(DynamicType.java:2507)
    at saden1.issues.bytebuddy.ServiceLocatorProxyNGTest.testSomeMethod(ServiceLocatorProxyNGTest.java:37)

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import net.bytebuddy.ByteBuddy;
import net.bytebuddy.ClassFileVersion;
import net.bytebuddy.NamingStrategy;
import net.bytebuddy.dynamic.ClassLoadingStrategy;
import net.bytebuddy.instrumentation.InvocationHandlerAdapter;
import static net.bytebuddy.instrumentation.method.matcher.MethodMatchers.*;
import net.bytebuddy.utility.RandomString;
import org.testng.annotations.Test;

public class ProxyNGTest {

    @Test
    public void testSomeMethod() throws InstantiationException, IllegalAccessException {
        Class<?> type = ProxyedInterface.class;
        ClassLoader classLoader = type.getClassLoader();

        Class<?> proxyType = new ByteBuddy(ClassFileVersion.JAVA_V8)
                .withNamingStrategy(new ProxyNamingStrategy(type))
                .subclass(Object.class)
                .implement(type)
                .method(isDeclaredBy(type))
                .intercept(InvocationHandlerAdapter.of(new ProxyInvocationHandler()))
                .make()
                .load(classLoader, ClassLoadingStrategy.Default.WRAPPER)
                .getLoaded();

        Object result = proxyType.newInstance();
    }

    public static interface ProxyedInterface {

        //fails on any setter that takes a primitive
        void setPrimitive(long value);

        //fails on any setter that takes a primitive
        void setPrimitive(long value, String string);

        //works
        void setObject(Long value);
    }

    public static class ProxyInvocationHandler implements InvocationHandler {

        @Override
        public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
            return method.invoke(proxy, args);
        }
    }

    public static class ProxyNamingStrategy implements NamingStrategy {

        private final Class<?> type;

        public ProxyNamingStrategy(Class<?> type) {
            this.type = type;
        }

        @Override
        public String name(UnnamedType unnamedType) {
            String packageName = type.getPackage().getName();
            String simpleName = type.getSimpleName();
            return String.format("test.%s_Proxy_%s", simpleName, RandomString.make());
        }

    }

}

[raphw]

This is indeed a bug. I simply forgot to apply a boxing assignment for the arguments. I just implemented a reproducing test and prepare a fix. I'll release a version 0.4.1 with this some minor bug-fixes later this day.

[raphw]

The bug-fix release 0.4.1 is already available in JCenter and is currently synchronized to Maven Central. It should be available from there in a couple of hours.