Struts example source code file (ViewSourceAction.java)

This example Struts source code file (ViewSourceAction.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

arraylist, bufferedreader, bufferedreader, inputstream, inputstream, io, ioexception, list, list, malformedurlexception, net, network, request, servlet, servletcontextaware, string, string, success, util, viewsourceaction

The Struts ViewSourceAction.java source code

/*
 * $Id: ViewSourceAction.java 570518 2007-08-28 18:26:48Z jholmes $
 *
 * 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.showcase.source;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;

import org.apache.struts2.ServletActionContext;
import org.apache.struts2.util.ServletContextAware;

import com.opensymphony.xwork2.ActionSupport;
import com.opensymphony.xwork2.util.ClassLoaderUtil;

/**
 * Processes configuration, page, and action class paths to create snippets
 * of the files for display.
 */
public class ViewSourceAction extends ActionSupport implements ServletContextAware {

    private String page;
    private String className;
    private String config;

    private List pageLines;
    private List classLines;
    private List configLines;

    private int configLine;
    private int padding = 10;

    private ServletContext servletContext;

    public String execute() throws MalformedURLException, IOException {

        if (page != null && page.trim().length() > 0) {

            InputStream in = ClassLoaderUtil.getResourceAsStream(page.substring(page.indexOf("//")+1), getClass());
            page = page.replace("//", "/");

            if (in == null) {
                in = servletContext.getResourceAsStream(page);
                while (in == null && page.indexOf('/', 1) > 0) {
                    page = page.substring(page.indexOf('/', 1));
                    in = servletContext.getResourceAsStream(page);
                }
            }
            pageLines = read(in, -1);

            if (in != null) {
                in.close();
            }
        }

        if (className != null && className.trim().length() > 0) {
            className = "/"+className.replace('.', '/') + ".java";
            InputStream in = getClass().getResourceAsStream(className);
            if (in == null) {
                in = servletContext.getResourceAsStream("/WEB-INF/src"+className);
            }
            classLines = read(in, -1);

            if (in != null) {
                in.close();
            }
        }

        String rootPath = ServletActionContext.getServletContext().getRealPath("/");
                
        if (config != null && config.trim().length() > 0 && (rootPath == null || config.startsWith(rootPath))) {
            int pos = config.lastIndexOf(':');
            configLine = Integer.parseInt(config.substring(pos+1));
            config = config.substring(0, pos).replace("//", "/");
            configLines = read(new URL(config).openStream(), configLine);
        }
        return SUCCESS;
    }


    /**
     * @param className the className to set
     */
    public void setClassName(String className) {
        this.className = className;
    }

    /**
     * @param config the config to set
     */
    public void setConfig(String config) {
        this.config = config;
    }

    /**
     * @param page the page to set
     */
    public void setPage(String page) {
        this.page = page;
    }

    /**
     * @param padding the padding to set
     */
    public void setPadding(int padding) {
        this.padding = padding;
    }



    /**
     * @return the classLines
     */
    public List getClassLines() {
        return classLines;
    }

    /**
     * @return the configLines
     */
    public List getConfigLines() {
        return configLines;
    }

    /**
     * @return the pageLines
     */
    public List getPageLines() {
        return pageLines;
    }

    /**
     * @return the className
     */
    public String getClassName() {
        return className;
    }

    /**
     * @return the config
     */
    public String getConfig() {
        return config;
    }

    /**
     * @return the page
     */
    public String getPage() {
        return page;
    }

    /**
     * @return the configLine
     */
    public int getConfigLine() {
        return configLine;
    }

    /**
     * @return the padding
     */
    public int getPadding() {
        return padding;
    }

    /**
     * Reads in a strea, optionally only including the target line number
     * and its padding
     *
     * @param in The input stream
     * @param targetLineNumber The target line number, negative to read all
     * @return A list of lines
     */
    private List read(InputStream in, int targetLineNumber) {
        List snippet = null;
        if (in != null) {
            snippet = new ArrayList();
            int startLine = 0;
            int endLine = Integer.MAX_VALUE;
            if (targetLineNumber > 0) {
                startLine = targetLineNumber - padding;
                endLine = targetLineNumber + padding;
            }
            try {
                BufferedReader reader = new BufferedReader(new InputStreamReader(in));

                int lineno = 0;
                String line;
                while ((line = reader.readLine()) != null) {
                    lineno++;
                    if (lineno >= startLine && lineno <= endLine) {
                        snippet.add(line);
                    }
                }
            } catch (Exception ex) {
                // ignoring as snippet not available isn't a big deal
            }
        }
        return snippet;
    }

    public void setServletContext(ServletContext arg0) {
        this.servletContext = arg0;
    }


}