Apache CXF example source code file (PluginLoader.java)

This example Apache CXF source code file (PluginLoader.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Apache CXF tags/keywords

databinding, frontend, io, log, log, logging, map, message, message, net, network, object, plugin, pluginloader, string, string, toolexception, toolexception, util

The Apache CXF PluginLoader.java source code

/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you 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 org.apache.cxf.tools.wsdlto.core;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;
import java.util.logging.Level;
import java.util.logging.Logger;

import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBElement;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Unmarshaller;

import org.apache.cxf.common.classloader.ClassLoaderUtils;
import org.apache.cxf.common.i18n.Message;
import org.apache.cxf.common.logging.LogUtils;
import org.apache.cxf.common.util.StringUtils;
import org.apache.cxf.tools.common.FrontEndGenerator;
import org.apache.cxf.tools.common.Processor;
import org.apache.cxf.tools.common.ToolException;
import org.apache.cxf.tools.common.toolspec.ToolContainer;
import org.apache.cxf.tools.plugin.DataBinding;
import org.apache.cxf.tools.plugin.FrontEnd;
import org.apache.cxf.tools.plugin.Generator;
import org.apache.cxf.tools.plugin.Plugin;

public final class PluginLoader {
    public static final Logger LOG = LogUtils.getL7dLogger(PluginLoader.class);
    public static final String DEFAULT_PROVIDER_NAME = "cxf.apache.org";
    private static PluginLoader pluginLoader;
    private static final String PLUGIN_FILE_NAME = "META-INF/tools-plugin.xml";

    private Map<String, Plugin> plugins = new LinkedHashMap();

    private Map<String, FrontEnd> frontends = new LinkedHashMap();

    private Map<String, DataBinding> databindings = new TreeMap();

    private Unmarshaller unmarshaller;

    private PluginLoader() {
        init();
    }

    private void init() {
        try {
            JAXBContext jc = JAXBContext.newInstance("org.apache.cxf.tools.plugin");
            unmarshaller = jc.createUnmarshaller();
            loadPlugins(ClassLoaderUtils.getResources(PLUGIN_FILE_NAME, getClass()));
        } catch (JAXBException e) {
            Message msg = new Message("JAXB_CONTEXT_INIT_FAIL", LOG);
            LOG.log(Level.SEVERE, msg.toString());
            throw new ToolException(msg);
        } catch (IOException ioe) {
            Message msg = new Message("LOAD_PLUGIN_EXCEPTION", LOG);
            LOG.log(Level.SEVERE, msg.toString());
            throw new ToolException(msg);
        }
    }

    public void refresh() {
        init();
    }

    private void loadPlugins(List<URL> pluginFiles) throws IOException {
        if (pluginFiles == null) {
            LOG.log(Level.WARNING, "FOUND_NO_PLUGINS");
            return;
        }

        for (URL url : pluginFiles) {
            loadPlugin(url);
        }
    }
    public static PluginLoader newInstance() {
        return new PluginLoader();
    }
    public static PluginLoader getInstance() {
        if (pluginLoader == null) {
            pluginLoader = new PluginLoader();
        }
        return pluginLoader;
    }

    public static void unload() {
        pluginLoader = null;
    }

    public void loadPlugin(URL url) throws IOException {
        try {
            LOG.log(Level.FINE, "PLUGIN_LOADING", url);
            loadPlugin(getPlugin(url));
        } catch (JAXBException e) {
            Message msg = new Message("PLUGIN_LOAD_FAIL", LOG, url);
            LOG.log(Level.SEVERE, msg.toString());
            throw new ToolException(msg, e);
        }
    }

    public void loadPlugin(String resource) {
        try {
            LOG.log(Level.FINE, "PLUGIN_LOADING", resource);
            loadPlugin(getPlugin(resource));
        } catch (JAXBException e) {
            Message msg = new Message("PLUGIN_LOAD_FAIL", LOG, resource);
            LOG.log(Level.SEVERE, msg.toString());
            throw new ToolException(msg, e);
        } catch (FileNotFoundException fe) {
            Message msg = new Message("PLUGIN_FILE_NOT_FOUND", LOG, resource);
            LOG.log(Level.SEVERE, msg.toString());
            throw new ToolException(msg, fe);
        }

    }

    protected void loadPlugin(Plugin plugin) {
        if (plugin.getFrontend().size() > 0) {
            LOG.log(Level.FINE, "FOUND_FRONTENDS", new Object[]{plugin.getName(),
                                                                plugin.getFrontend().size()});
        }

        for (FrontEnd frontend : plugin.getFrontend()) {
            LOG.log(Level.FINE, "LOADING_FRONTEND", new Object[]{frontend.getName(), plugin.getName()});
            if (StringUtils.isEmpty(frontend.getName())) {
                LOG.log(Level.WARNING, "FRONTEND_MISSING_NAME", plugin.getName());
                continue;
            }

            if (frontends.containsKey(frontend.getName())
                && DEFAULT_PROVIDER_NAME.equals(plugin.getProvider())) {
                Message msg = new Message("REPLACED_DEFAULT_FRONTEND", LOG, frontend.getName());
                LOG.log(Level.INFO, msg.toString());
                continue;
            }
            frontends.put(frontend.getName(), frontend);
        }

        if (plugin.getDatabinding().size() > 0) {
            LOG.log(Level.FINE, "FOUND_DATABINDINGS", new Object[]{plugin.getName(),
                                                                   plugin.getDatabinding().size()});
        }

        for (DataBinding databinding : plugin.getDatabinding()) {
            LOG.log(Level.FINE, "LOADING_DATABINDING", new Object[]{databinding.getName(), plugin.getName()});
            if (StringUtils.isEmpty(databinding.getName())) {
                LOG.log(Level.WARNING, "DATABINDING_MISSING_NAME", plugin.getName());
                continue;
            }
            if (databindings.containsKey(databinding.getName())
                && DEFAULT_PROVIDER_NAME.equals(plugin.getProvider())) {
                Message msg = new Message("REPLACED_DEFAULT_DATABINDING", LOG, databinding.getName());
                LOG.log(Level.INFO, msg.toString());
                continue;
            }
            databindings.put(databinding.getName(), databinding);
        }
    }

    protected Plugin getPlugin(URL url) throws IOException, JAXBException, FileNotFoundException {
        Plugin plugin = plugins.get(url.toString());
        InputStream is = null;
        if (plugin == null) {
            is = url.openStream();
            plugin = getPlugin(is);
            if (plugin == null || StringUtils.isEmpty(plugin.getName())) {
                Message msg = new Message("PLUGIN_LOAD_FAIL", LOG, url);
                LOG.log(Level.SEVERE, msg.toString());
                throw new ToolException(msg);
            }
            plugins.put(url.toString(), plugin);
        }
        if (is == null) {
            return getPlugin(url.toString());
        }
        return plugin;
    }

    protected Plugin getPlugin(String resource) throws JAXBException, FileNotFoundException {
        Plugin plugin = plugins.get(resource);
        if (plugin == null) {
            InputStream is = null;
            if (new File(resource).exists()) {
                is = new BufferedInputStream(new FileInputStream(new File(resource)));
            } else {
                is = getClass().getResourceAsStream(resource);
            }

            if (is == null) {
                Message msg = new Message("PLUGIN_MISSING", LOG, resource);
                LOG.log(Level.SEVERE, msg.toString());
                throw new ToolException(msg);
            }
            plugin = getPlugin(is);
            if (plugin == null || StringUtils.isEmpty(plugin.getName())) {
                Message msg = new Message("PLUGIN_LOAD_FAIL", LOG, resource);
                LOG.log(Level.SEVERE, msg.toString());
                throw new ToolException(msg);
            }
            plugins.put(resource, plugin);
        }
        return plugin;
    }

    private Plugin getPlugin(InputStream is) throws JAXBException {
        return (Plugin) ((JAXBElement<?>)unmarshaller.unmarshal(is)).getValue();
    }

    public FrontEnd getFrontEnd(String name) {
        FrontEnd frontend = frontends.get(name);

        if (frontend == null) {
            Message msg = new Message("FRONTEND_MISSING", LOG, name);
            throw new ToolException(msg);
        }
        return frontend;
    }

    private String getGeneratorClass(FrontEnd frontend, Generator generator) {
        String fullPackage = generator.getPackage();
        if (StringUtils.isEmpty(fullPackage)) {
            fullPackage = frontend.getGenerators().getPackage();
        }
        if (StringUtils.isEmpty(fullPackage)) {
            fullPackage = frontend.getPackage();
        }
        return fullPackage + "." + generator.getName();
    }

    private List<FrontEndGenerator> getFrontEndGenerators(FrontEnd frontend) {
        List<FrontEndGenerator> generators = new ArrayList();

        String fullClzName = null;
        try {
            for (Generator generator : frontend.getGenerators().getGenerator()) {
                fullClzName = getGeneratorClass(frontend, generator);
                Class clz = ClassLoaderUtils.loadClass(fullClzName, this.getClass());
                generators.add((FrontEndGenerator)clz.newInstance());
            }
        } catch (Exception e) {
            Message msg = new Message("FRONTEND_PROFILE_LOAD_FAIL", LOG, fullClzName);
            LOG.log(Level.SEVERE, msg.toString());
            throw new ToolException(msg, e);
        }

        return generators;
    }

    private FrontEndProfile loadFrontEndProfile(String fullClzName) {
        FrontEndProfile profile = null;
        try {
            Class clz = ClassLoaderUtils.loadClass(fullClzName, this.getClass());
            profile = (FrontEndProfile)clz.newInstance();
        } catch (Exception e) {
            Message msg = new Message("FRONTEND_PROFILE_LOAD_FAIL", LOG, fullClzName);
            LOG.log(Level.SEVERE, msg.toString());
            throw new ToolException(msg, e);
        }
        return profile;
    }

    private Processor loadProcessor(String fullClzName) {
        Processor processor = null;
        try {
            processor = (Processor) ClassLoaderUtils.loadClass(fullClzName, getClass()).newInstance();
        } catch (Exception e) {
            Message msg = new Message("LOAD_PROCESSOR_FAILED", LOG, fullClzName);
            LOG.log(Level.SEVERE, msg.toString());
            throw new ToolException(msg, e);
        }
        return processor;
    }

    private Class<? extends ToolContainer> loadContainerClass(String fullClzName) {
        Class<?> clz = null;
        try {
            clz = ClassLoaderUtils.loadClass(fullClzName, getClass());
        } catch (Exception e) {
            Message msg = new Message("LOAD_CONTAINER_CLASS_FAILED", LOG, fullClzName);
            LOG.log(Level.SEVERE, msg.toString());
            throw new ToolException(msg, e);
        }

        if (!ToolContainer.class.isAssignableFrom(clz)) {
            Message message = new Message("CLZ_SHOULD_IMPLEMENT_INTERFACE", LOG, clz.getName());
            LOG.log(Level.SEVERE, message.toString());
            throw new ToolException(message);
        }

        return clz.asSubclass(ToolContainer.class);
    }

    private String getFrontEndProfileClass(FrontEnd frontend) {
        if (StringUtils.isEmpty(frontend.getProfile())) {
            return "org.apache.cxf.tools.wsdlto.core.FrontEndProfile";
        }
        return frontend.getPackage() + "." + frontend.getProfile();
    }

    private String getProcessorClass(FrontEnd frontend) {
        String pkgName = frontend.getProcessor().getPackage();
        if (StringUtils.isEmpty(pkgName)) {
            pkgName = frontend.getPackage();
        }
        return pkgName + "." + frontend.getProcessor().getName();
    }

    private String getContainerClass(FrontEnd frontend) {
        return getContainerPackage(frontend) + "." + frontend.getContainer().getName();
    }

    private String getContainerPackage(FrontEnd frontend) {
        String pkgName = frontend.getContainer().getPackage();
        if (StringUtils.isEmpty(pkgName)) {
            pkgName = frontend.getPackage();
        }
        return pkgName;
    }

    private String getToolspec(FrontEnd frontend) {
        String toolspec = frontend.getContainer().getToolspec();
        return "/" + getContainerPackage(frontend).replace(".", "/") + "/" + toolspec;
    }

    @SuppressWarnings("unchecked")
    private AbstractWSDLBuilder<? extends Object> loadBuilder(String fullClzName) {
        AbstractWSDLBuilder<? extends Object> builder = null;
        try {
            builder = (AbstractWSDLBuilder<? extends Object>) ClassLoaderUtils
                .loadClass(fullClzName, getClass()).newInstance();

        } catch (Exception e) {
            Message msg = new Message("LOAD_PROCESSOR_FAILED", LOG, fullClzName);
            LOG.log(Level.SEVERE, msg.toString());
            throw new ToolException(msg, e);
        }
        return builder;
    }

    private String getBuilderClass(FrontEnd frontend) {
        String pkgName = frontend.getBuilder().getPackage();
        if (StringUtils.isEmpty(pkgName)) {
            pkgName = frontend.getPackage();
        }
        return pkgName + "." + frontend.getBuilder().getName();
    }

    public FrontEndProfile getFrontEndProfile(String name) {
        FrontEndProfile profile = null;
        FrontEnd frontend = getFrontEnd(name);

        profile = loadFrontEndProfile(getFrontEndProfileClass(frontend));

        for (FrontEndGenerator generator : getFrontEndGenerators(frontend)) {
            profile.registerGenerator(generator);
        }

        if (frontend.getProcessor() != null) {
            profile.setProcessor(loadProcessor(getProcessorClass(frontend)));
        }
        if (frontend.getContainer() != null) {
            profile.setContainerClass(loadContainerClass(getContainerClass(frontend)));
            profile.setToolspec(getToolspec(frontend));
        }
        if (frontend.getBuilder() != null) {
            profile.setWSDLBuilder(loadBuilder(getBuilderClass(frontend)));
        }
        return profile;
    }

    public DataBinding getDataBinding(String name) {
        DataBinding databinding = databindings.get(name);
        if (databinding == null) {
            Message msg = new Message("DATABINDING_MISSING", LOG, name);
            throw new ToolException(msg);
        }
        return databinding;
    }

    private DataBindingProfile loadDataBindingProfile(String fullClzName) {
        DataBindingProfile profile = null;
        try {
            profile = (DataBindingProfile)ClassLoaderUtils.loadClass(fullClzName,
                                                                     getClass()).newInstance();
        } catch (Exception e) {
            Message msg = new Message("DATABINDING_PROFILE_LOAD_FAIL", LOG, fullClzName);
            LOG.log(Level.SEVERE, msg.toString());
            throw new ToolException(msg);
        }
        return profile;
    }

    public DataBindingProfile getDataBindingProfile(String name) {
        DataBindingProfile profile = null;
        DataBinding databinding = getDataBinding(name);
        profile = loadDataBindingProfile(databinding.getPackage() + "." + databinding.getProfile());
        return profile;
    }

    public Map<String, FrontEnd> getFrontEnds() {
        return this.frontends;
    }

    public Map<String, DataBinding> getDataBindings() {
        return this.databindings;
    }

    public Map<String, Plugin> getPlugins() {
        return this.plugins;
    }
}