com.flipkart.phantom.task.spi.registry.HandlerConfigInfo.java Source code

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Here is the source code for com.flipkart.phantom.task.spi.registry.HandlerConfigInfo.java

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/*
 * Copyright 2012-2015, the original author or authors.
 *
 * 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.flipkart.phantom.task.spi.registry;

import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.context.support.FileSystemXmlApplicationContext;

import java.io.File;

/**
 * The <code>HandlerConfigInfo</code> class is a structure that holds proxy handler configuration information and the ApplicationContext for the proxy handler
 * 
 * @author Regunath B
 * @version 1.0, 14 Mar 2013
 */
public class HandlerConfigInfo {

    /** The sub-folder containing proxy handler and dependent binaries. This is used in addition to the proxy runtime classpath.
     *  This path is relative to the location where ServiceProxyFrameworkConstants.SPRING_PROXY_HANDLER_CONFIG file is found 
     */
    public static final String BINARIES_PATH = "lib";

    /** The prefix to be added to file absolute paths when loading Spring XMLs using the FileSystemXmlApplicationContext*/
    public static final String FILE_PREFIX = "file:";

    /** The the ServiceProxyFrameworkConstants.SPRING_PROXY_HANDLER_CONFIG file containing proxy handler bean */
    private File xmlConfigFile;

    /** The path to proxy handler and dependent binaries*/
    private String binariesPath = HandlerConfigInfo.BINARIES_PATH;

    /** The Spring ApplicationContext initialized using information contained in this HandlerConfigInfo*/
    private AbstractApplicationContext proxyHandlerContext;

    /**
     * Constructors
     */
    public HandlerConfigInfo(File xmlConfigFile) {
        this.xmlConfigFile = xmlConfigFile;
    }

    public HandlerConfigInfo(File xmlConfigFile, String binariesPath) {
        this(xmlConfigFile);
        this.binariesPath = binariesPath;
    }

    public HandlerConfigInfo(File xmlConfigFile, String binariesPath,
            AbstractApplicationContext proxyHandlerContext) {
        this(xmlConfigFile, binariesPath);
        this.proxyHandlerContext = proxyHandlerContext;
    }

    /**
     * Loads and returns an AbstractApplicationContext using data contained in this class
     * @return the proxy handler's AbstractApplicationContext
     */
    public AbstractApplicationContext loadProxyHandlerContext(ClassLoader classLoader,
            AbstractApplicationContext applicationContext) {
        ClassLoader existingTCCL = Thread.currentThread().getContextClassLoader();
        // set the custom classloader as the tccl for loading the proxy handler
        Thread.currentThread().setContextClassLoader(classLoader);
        // add the "file:" prefix to file names to get around strange behavior of FileSystemXmlApplicationContext that converts absolute path 
        // to relative path
        this.proxyHandlerContext = new FileSystemXmlApplicationContext(
                new String[] { FILE_PREFIX + this.xmlConfigFile.getAbsolutePath() }, applicationContext);
        // now reset the thread's TCCL to the one that existed prior to loading the proxy handler
        Thread.currentThread().setContextClassLoader(existingTCCL);
        return this.proxyHandlerContext;
    }

    /**
     * Overriden super type method. Returns true if the path to the proxy handler context is the same i.e. loaded from the same file
     * @see java.lang.Object#equals(java.lang.Object)
     */
    public boolean equals(Object object) {
        HandlerConfigInfo otherConfigInfo = (HandlerConfigInfo) object;
        return this.getXmlConfigFile().getAbsolutePath()
                .equalsIgnoreCase(otherConfigInfo.getXmlConfigFile().getAbsolutePath());
    }

    /**
     * Overriden superclass method. Prints the xmlConfigFile details
     * @see java.lang.Object#toString()
     */
    public String toString() {
        return "HandlerConfigInfo [xmlConfigFile=" + xmlConfigFile + ", binariesPath=" + binariesPath + "]";
    }

    /** Getter methods*/
    /**
     * Returns the proxy handler's ApplicationContext, if loaded, else null
     * @return null or the proxy handler's AbstractApplicationContext
     */
    public AbstractApplicationContext getProxyHandlerContext() {
        return this.proxyHandlerContext;
    }

    public File getXmlConfigFile() {
        return this.xmlConfigFile;
    }

    public String getBinariesPath() {
        return this.binariesPath;
    }

}