Struts example source code file (ShellAction.java)

This example Struts source code file (ShellAction.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

actionsupport, apache, bytearrayoutputstream, bytearrayoutputstream, exception, felix, io, printstream, printstream, servicereference, shell, shellservice, shellservice, string, string

The Struts ShellAction.java source code

/*
 * $Id$
 *
 * 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.osgi.admin.actions;

import java.io.ByteArrayOutputStream;
import java.io.PrintStream;

import org.apache.struts2.osgi.DefaultBundleAccessor;
import org.apache.felix.shell.ShellService;
import org.osgi.framework.ServiceReference;

import com.opensymphony.xwork2.Action;
import com.opensymphony.xwork2.ActionSupport;

/**
 * This action executes commands on the Felix Shell
 */
public class ShellAction extends ActionSupport {
    private String command;
    private String output;

    public String execute() {
        // get service
        ByteArrayOutputStream outByteStream = new ByteArrayOutputStream();
        ByteArrayOutputStream errByteStream = new ByteArrayOutputStream();
        PrintStream outStream = new PrintStream(outByteStream);
        PrintStream errStream = new PrintStream(errByteStream);

        String outString = null;
        String errString = null;
        try {
            executeCommand(command, outStream, errStream);
            outString = outByteStream.toString().trim();
            errString = errByteStream.toString().trim();
        } catch (Exception e) {
            errString = e.getMessage();
        } finally {
            outStream.close();
            errStream.close();
        }

        output = errString != null && errString.length() > 0 ? errString : outString;
        return Action.SUCCESS;
    }

    public String getCommand() {
        return command;
    }

    public void setCommand(String command) {
        this.command = command;
    }

    public String getOutput() {
        return output;
    }

    public void executeCommand(String commandLine, PrintStream out, PrintStream err) throws Exception {
        ShellService shellService = getShellService();
        if (shellService != null)
            shellService.executeCommand(commandLine, out, err);
        else
            err.println("Apache Felix Shell service is not installed");
    }

    private ShellService getShellService() {
        //bundle can be de-activated, so keeping a reference aorund is not a good idea
        DefaultBundleAccessor bundleAcessor = DefaultBundleAccessor.getInstance();
        ServiceReference ref = bundleAcessor.getServiceReference(ShellService.class.getName());
        return (ShellService) bundleAcessor.getService(ref);
    }
}