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Struts example source code file (CodebehindUnknownHandler.java)

This example Struts source code file (CodebehindUnknownHandler.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 - Struts tags/keywords

actionconfig, actionconfig, inject, inject, malformedurlexception, net, network, object, packageconfig, result, servlet, string, string, stringbuilder, unable, unable, util, xworkexception

The Struts CodebehindUnknownHandler.java source code

/*
 * $Id: CodebehindUnknownHandler.java 673081 2008-07-01 13:49:01Z jeromy $
 *
 * 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.struts2.codebehind;

import com.opensymphony.xwork2.*;
import com.opensymphony.xwork2.config.Configuration;
import com.opensymphony.xwork2.config.ConfigurationException;
import com.opensymphony.xwork2.config.entities.*;
import com.opensymphony.xwork2.config.providers.InterceptorBuilder;
import com.opensymphony.xwork2.inject.Inject;
import com.opensymphony.xwork2.util.logging.Logger;
import com.opensymphony.xwork2.util.logging.LoggerFactory;
import org.apache.struts2.util.ClassLoaderUtils;

import javax.servlet.ServletContext;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.Map;

/**
 * Uses code-behind conventions to solve the two unknown problems.  
 */
public class CodebehindUnknownHandler implements UnknownHandler {

    protected String defaultPackageName;
    protected ServletContext servletContext;
    protected Map<String,ResultTypeConfig> resultsByExtension;
    protected String templatePathPrefix;
    protected Configuration configuration;
    protected ObjectFactory objectFactory;
    
    protected static final Logger LOG = LoggerFactory.getLogger(CodebehindUnknownHandler.class);

    @Inject
    public CodebehindUnknownHandler(@Inject("struts.codebehind.defaultPackage") String defaultPackage, 
                                    @Inject Configuration configuration) {

        this.configuration = configuration;
        this.defaultPackageName = defaultPackage;
        resultsByExtension = new LinkedHashMap<String,ResultTypeConfig>();
        PackageConfig parentPackage = configuration.getPackageConfig(defaultPackageName);
        if (parentPackage == null) {
            throw new ConfigurationException("Unknown parent package: "+parentPackage);
        }    
        Map<String,ResultTypeConfig> results = parentPackage.getAllResultTypeConfigs();
        
        resultsByExtension.put("jsp", results.get("dispatcher"));
        resultsByExtension.put("vm", results.get("velocity"));
        resultsByExtension.put("ftl", results.get("freemarker"));
       
    }                                

    @Inject("struts.codebehind.pathPrefix")
    public void setPathPrefix(String prefix) {
        this.templatePathPrefix=prefix;
    }

    @Inject
    public void setServletContext(ServletContext servletContext) {
        this.servletContext = servletContext;
    }
    
    @Inject
    public void setObjectFactory(ObjectFactory objectFactory) {
        this.objectFactory = objectFactory;
    }
    
    public ActionConfig handleUnknownAction(String namespace, String actionName)
            throws XWorkException {
        String pathPrefix = determinePath(templatePathPrefix, namespace);
        ActionConfig actionConfig = null;
        for (String ext : resultsByExtension.keySet()) {
            if (LOG.isDebugEnabled()) {
                LOG.debug("Trying to locate unknown action template with extension ."+ext+" in directory "+pathPrefix);
            }
            String path = string(pathPrefix, actionName, "." , ext);
            try {
                if (locateTemplate(path) != null) {
                    actionConfig = buildActionConfig(path, namespace, actionName, resultsByExtension.get(ext));
                    break;
                }
            } catch (MalformedURLException e) {
                LOG.warn("Unable to parse template path: "+path+", skipping...");
            }
        }
        return actionConfig;
    }

    /** Create a new ActionConfig in the default package, with the default interceptor stack and a single result */
    protected ActionConfig buildActionConfig(String path, String namespace, String actionName, ResultTypeConfig resultTypeConfig) {
        final PackageConfig pkg = configuration.getPackageConfig(defaultPackageName);
        return new ActionConfig.Builder(defaultPackageName, "execute", pkg.getDefaultClassRef())
                .addInterceptors(InterceptorBuilder.constructInterceptorReference(new InterceptorLocator() {
                    public Object getInterceptorConfig(String name) {
                        return pkg.getAllInterceptorConfigs().get(name); // recurse package hiearchy
                    }
                }, pkg.getFullDefaultInterceptorRef(),
                Collections.EMPTY_MAP, null, objectFactory))
                .addResultConfig(new ResultConfig.Builder(Action.SUCCESS, resultTypeConfig.getClassName())
                        .addParams(resultTypeConfig.getParams())
                        .addParam(resultTypeConfig.getDefaultResultParam(), path)
                        .build())
                .build();
    }

    public Result handleUnknownResult(ActionContext actionContext, String actionName, 
            ActionConfig actionConfig, String resultCode) throws XWorkException {
        
        Result result = null;
        PackageConfig pkg = configuration.getPackageConfig(actionConfig.getPackageName());
        String ns = pkg.getNamespace();
        String pathPrefix = determinePath(templatePathPrefix, ns);

        for (String ext : resultsByExtension.keySet()) {
            if (LOG.isDebugEnabled()) {
                LOG.debug("Trying to locate result with extension ."+ext+" in directory "+pathPrefix);
            }
            String path = string(pathPrefix, actionName, "-", resultCode, "." , ext);
            try {
                if (locateTemplate(path) != null) {
                    result = buildResult(path, resultCode, resultsByExtension.get(ext), actionContext);
                    break;
                }
            } catch (MalformedURLException e) {
                LOG.warn("Unable to parse template path: "+path+", skipping...");
            }
            
            path = string(pathPrefix, actionName, "." , ext);
            try {
                if (locateTemplate(path) != null) {
                    result = buildResult(path, resultCode, resultsByExtension.get(ext), actionContext);
                    break;
                }
            } catch (MalformedURLException e) {
                LOG.warn("Unable to parse template path: "+path+", skipping...");
            }
        }
        
        return result;
    }
    
    protected Result buildResult(String path, String resultCode, ResultTypeConfig config, ActionContext invocationContext) {
        ResultConfig resultConfig = new ResultConfig.Builder(resultCode, config.getClassName())
            .addParams(config.getParams())
            .addParam(config.getDefaultResultParam(), path)
            .build();
        try {
            return objectFactory.buildResult(resultConfig, invocationContext.getContextMap());
        } catch (Exception e) {
            throw new XWorkException("Unable to build codebehind result", e, resultConfig);
        }
    }

    protected String string(String... parts) {
        StringBuilder sb = new StringBuilder();
        for (String part : parts) {
            sb.append(part);
        }
        return sb.toString();
    }

    protected String joinPaths(boolean leadingSlash, boolean trailingSlash, String... parts) {
        StringBuilder sb = new StringBuilder();
        if (leadingSlash) {
            sb.append("/");
        }
        for (String part : parts) {
            if (sb.length() > 0 && sb.charAt(sb.length()-1) != '/') {
                sb.append("/");
            }
            sb.append(stripSlashes(part));
        }
        if (trailingSlash) {
            if (sb.length() > 0 && sb.charAt(sb.length()-1) != '/') {
                sb.append("/");
            }
        }
        return sb.toString();
    }

    protected String determinePath(String prefix, String ns) {        
        return joinPaths(true, true, prefix, ns);
    }

    protected String stripLeadingSlash(String path) {
        String result;
        if (path != null) {
            if (path.length() > 0) {
                if (path.charAt(0) == '/') {
                    result = path.substring(1);
                } else {
                    result = path;
                }
            } else {
                result = path;
            }
        } else {
            result = "";
        }

        return result;
    }

    protected String stripTrailingSlash(String path) {
        String result;

        if (path != null) {
            if (path.length() > 0) {
                if (path.charAt(path.length() - 1) == '/') {
                    result = path.substring(0, path.length()-1);
                } else {
                    result = path;
                }
            } else {
                result = path;
            }
        } else {
            result = "";
        }

        return result;
    }

    protected String stripSlashes(String path) {
        return stripLeadingSlash(stripTrailingSlash(path));
    }

    URL locateTemplate(String path) throws MalformedURLException {
        URL template = servletContext.getResource(path);
        if (template != null) {
            if (LOG.isDebugEnabled()) {
                LOG.debug("Loaded template '" + path + "' from servlet context.");
            }
        } else {
            template = ClassLoaderUtils.getResource(stripLeadingSlash(path), getClass());
            if (template != null && LOG.isDebugEnabled()) {
                LOG.debug("Loaded template '" + stripLeadingSlash(path) + "' from class path.");
            }
        }
        return template;
    }


    /**
     * Not used
     */
	public Object handleUnknownActionMethod(Object action, String methodName) throws NoSuchMethodException {
		throw new NoSuchMethodException();
	}

}

Other Struts examples (source code examples)

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