com.googlecode.jinahya.commons.codec.EncoderProxy Maven / Gradle / Ivy
/*
* Copyright 2012 Jin Kwon .
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.googlecode.jinahya.commons.codec;
import java.lang.reflect.Method;
/**
* An abstract class for {@code org.apache.commons.codec.Encoder} proxies.
*
* @author Jin Kwon
* @param encoder (delegate) type parameter.
*/
public abstract class EncoderProxy extends AbstractEncoderProxy {
/**
* {@code org.apache.commons.codec.Encoder}.
*/
private static final Class ENCODER;
static {
try {
ENCODER = Class.forName("org.apache.commons.codec.Encoder");
} catch (final ClassNotFoundException cnfe) {
throw new InstantiationError(cnfe.getMessage());
}
}
/**
* {@code encode(Ljava/lang/Object;)Ljava/lang/Object;}.
*/
private static final Method ENCODE;
static {
try {
ENCODE = ENCODER.getMethod("encode", Object.class);
} catch (final NoSuchMethodException nsme) {
throw new InstantiationError(nsme.getMessage());
}
}
/**
* Creates a new proxy instance for
* {@code org.apache.commons.codec.Encoder}.
*
* @param proxy type parameter
* @param encoder (delegate) type parameter
* @param proxyType proxy type
* @param encoderType encoder type
* @param encoder encoder instance
*
* @return a new proxy instance.
*/
protected static , T> Object newInstance(
final Class
proxyType, final Class encoderType, final T encoder) {
if (proxyType == null) {
throw new NullPointerException("proxyType");
}
if (!EncoderProxy.class.isAssignableFrom(proxyType)) {
throw new IllegalArgumentException(
"proxyType(" + proxyType + ") is not assignable to "
+ EncoderProxy.class);
}
return newInstance(ENCODER.getClassLoader(), new Class[]{ENCODER},
proxyType, encoderType, encoder);
}
/**
* Creates a new instance.
*
* @param encoder the delegate
*/
protected EncoderProxy(final T encoder) {
super(encoder);
}
@Override
public Object invoke(final Object proxy, final Method method,
final Object[] args)
throws Throwable {
if (ENCODE.equals(method)) {
return encode(args[0]);
}
throw new UnsupportedOperationException("unsupported: " + method);
}
/**
* Encodes given {@code source}.
*
* @param source source to encode.
*
* @return encoding result.
*
* @throws Throwable if failed to encode.
*/
protected abstract Object encode(final Object source) throws Throwable;
}