com.sxj.jsonrpc.client.spring.AutoJsonRpcClientProxyCreator.java Source code

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Here is the source code for com.sxj.jsonrpc.client.spring.AutoJsonRpcClientProxyCreator.java

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/*
The MIT License (MIT)
    
Copyright (c) 2014 jsonrpc4j
    
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
    
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
    
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
 */

package com.sxj.jsonrpc.client.spring;

import static java.lang.String.format;
import static org.springframework.util.ClassUtils.convertClassNameToResourcePath;

import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.beans.factory.support.BeanDefinitionBuilder;
import org.springframework.beans.factory.support.DefaultListableBeanFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.core.io.Resource;
import org.springframework.core.type.AnnotationMetadata;
import org.springframework.core.type.ClassMetadata;
import org.springframework.core.type.classreading.MetadataReader;
import org.springframework.core.type.classreading.SimpleMetadataReaderFactory;

import com.sxj.jsonrpc.annotation.JsonRpcService;

/**
 * Auto-creates proxies for service interfaces annotated with
 * {@link JsonRpcService}.
 */
public class AutoJsonRpcClientProxyCreator implements BeanFactoryPostProcessor, ApplicationContextAware {

    private static final Log LOG = LogFactory.getLog(AutoJsonRpcClientProxyCreator.class);

    private ApplicationContext applicationContext;

    private String scanPackage;

    private URL baseUrl;

    public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
        SimpleMetadataReaderFactory metadataReaderFactory = new SimpleMetadataReaderFactory(applicationContext);
        DefaultListableBeanFactory dlbf = (DefaultListableBeanFactory) beanFactory;
        String resolvedPath = resolvePackageToScan();
        LOG.debug(format("Scanning '%s' for JSON-RPC service interfaces.", resolvedPath));
        try {
            for (Resource resource : applicationContext.getResources(resolvedPath)) {
                if (resource.isReadable()) {
                    MetadataReader metadataReader = metadataReaderFactory.getMetadataReader(resource);
                    ClassMetadata classMetadata = metadataReader.getClassMetadata();
                    AnnotationMetadata annotationMetadata = metadataReader.getAnnotationMetadata();
                    String jsonRpcPathAnnotation = JsonRpcService.class.getName();
                    if (annotationMetadata.isAnnotated(jsonRpcPathAnnotation)) {
                        String className = classMetadata.getClassName();
                        String path = (String) annotationMetadata.getAnnotationAttributes(jsonRpcPathAnnotation)
                                .get("value");
                        boolean useNamedParams = (Boolean) annotationMetadata
                                .getAnnotationAttributes(jsonRpcPathAnnotation).get("useNamedParams");
                        LOG.debug(format("Found JSON-RPC service to proxy [%s] on path '%s'.", className, path));
                        registerJsonProxyBean(dlbf, className, path, useNamedParams);
                    }
                }
            }
        } catch (IOException e) {
            throw new RuntimeException(format("Cannot scan package '%s' for classes.", resolvedPath), e);
        }
    }

    /**
     * Converts the scanPackage to something that the resource loader can
     * handle.
     */
    private String resolvePackageToScan() {
        return "classpath*:" + convertClassNameToResourcePath(scanPackage) + "/**/*.class";
    }

    /**
     * Registers a new proxy bean with the bean factory.
     */
    private void registerJsonProxyBean(DefaultListableBeanFactory dlbf, String className, String path,
            boolean useNamedParams) {
        BeanDefinitionBuilder beanDefinitionBuilder = BeanDefinitionBuilder
                .rootBeanDefinition(JsonProxyFactoryBean.class).addPropertyValue("serviceUrl", appendBasePath(path))
                .addPropertyValue("serviceInterface", className).addPropertyValue("useNamedParams", useNamedParams);
        ;
        dlbf.registerBeanDefinition(className + "-clientProxy", beanDefinitionBuilder.getBeanDefinition());
    }

    /**
     * Appends the base path to the path found in the interface.
     */
    private String appendBasePath(String path) {
        try {
            return new URL(baseUrl, path).toString();
        } catch (MalformedURLException e) {
            throw new RuntimeException(format("Cannot combine URLs '%s' and '%s' to valid URL.", baseUrl, path), e);
        }
    }

    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        this.applicationContext = applicationContext;
    }

    public void setBaseUrl(URL baseUrl) {
        this.baseUrl = baseUrl;
    }

    public void setScanPackage(String scanPackage) {
        this.scanPackage = scanPackage;
    }

}