com.netflix.paas.config.base.JavaAssistArchaeusConfigurationFactory.java Source code

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Here is the source code for com.netflix.paas.config.base.JavaAssistArchaeusConfigurationFactory.java

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/*******************************************************************************
 * /***
 *  *
 *  *  Copyright 2013 Netflix, Inc.
 *  *
 *  *     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.netflix.paas.config.base;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.Map;

import net.sf.cglib.proxy.Enhancer;

import org.apache.commons.configuration.AbstractConfiguration;

import com.google.common.base.Supplier;
import com.netflix.config.ConfigurationManager;
import com.netflix.config.DynamicPropertyFactory;
import com.netflix.paas.config.ConfigurationFactory;

public class JavaAssistArchaeusConfigurationFactory implements ConfigurationFactory {

    @Override
    public <T> T get(Class<T> configClass) throws Exception {
        return get(configClass, DynamicPropertyFactory.getInstance(), ConfigurationManager.getConfigInstance());
    }

    @SuppressWarnings({ "unchecked", "static-access" })
    public <T> T get(Class<T> configClass, DynamicPropertyFactory propertyFactory,
            AbstractConfiguration configuration) throws Exception {
        final Map<String, Supplier<?>> methods = ConfigurationProxyUtils.getMethodSuppliers(configClass,
                propertyFactory, configuration);

        if (configClass.isInterface()) {
            Class<?> proxyClass = Proxy.getProxyClass(configClass.getClassLoader(), new Class[] { configClass });

            return (T) proxyClass.getConstructor(new Class[] { InvocationHandler.class })
                    .newInstance(new Object[] { new InvocationHandler() {
                        @Override
                        public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                            Supplier<?> supplier = (Supplier<?>) methods.get(method.getName());
                            if (supplier == null) {
                                return method.invoke(proxy, args);
                            }
                            return supplier.get();
                        }
                    } });
        } else {
            final Enhancer enhancer = new Enhancer();
            final Object obj = (T) enhancer.create(configClass, new net.sf.cglib.proxy.InvocationHandler() {
                @Override
                public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                    Supplier<?> supplier = (Supplier<?>) methods.get(method.getName());
                    if (supplier == null) {
                        return method.invoke(proxy, args);
                    }
                    return supplier.get();
                }
            });

            ConfigurationProxyUtils.assignFieldValues(obj, configClass, propertyFactory, configuration);
            return (T) obj;
        }
    }

}