Java tutorial
/* * 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 com.sludev.commons.vfs.simpleshell; import com.sludev.commons.vfs2.provider.azure.AzConstants; import com.sludev.commons.vfs2.provider.azure.AzFileProvider; import com.sludev.commons.vfs2.provider.azure.AzFileSystemConfigBuilder; import java.io.File; import java.io.IOException; import java.io.PrintWriter; import java.nio.file.Path; import java.nio.file.Paths; import java.text.DateFormat; import java.util.ArrayList; import java.util.Date; import java.util.LinkedList; import java.util.List; import java.util.Properties; import java.util.StringTokenizer; import jline.console.ConsoleReader; import jline.console.completer.AggregateCompleter; import jline.console.completer.ArgumentCompleter; import jline.console.completer.Completer; import jline.console.completer.FileNameCompleter; import jline.console.completer.StringsCompleter; import jline.console.history.FileHistory; import org.apache.commons.vfs2.FileContent; import org.apache.commons.vfs2.FileObject; import org.apache.commons.vfs2.FileSystemException; import org.apache.commons.vfs2.FileSystemManager; import org.apache.commons.vfs2.FileType; import org.apache.commons.vfs2.FileUtil; import org.apache.commons.vfs2.Selectors; import org.apache.commons.vfs2.auth.StaticUserAuthenticator; import org.apache.commons.vfs2.impl.DefaultFileSystemManager; import org.apache.commons.vfs2.provider.local.DefaultLocalFileProvider; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * A simple command-line shell for performing file operations. * * @author Kervin Pierre * @author <a href="mailto:adammurdoch@apache.org">Adam Murdoch</a> * @author Gary D. Gregory */ public class SimpleShell { private static final Logger log = LoggerFactory.getLogger(SimpleShell.class); private FileSystemManager mgr; private FileObject cwd; private Properties mainProperties; private ConsoleReader conReader; public static void main(final String[] args) { try { (new SimpleShell()).go(); } catch (Exception ex) { log.error(String.format("Error running shell"), ex); System.exit(1); } System.exit(0); } public SimpleShell() throws FileSystemException, IOException { mainProperties = SimpleShellProperties.GetProperties(); String currAccountStr = mainProperties.getProperty("azure.account.name"); // .blob.core.windows.net String currKey = mainProperties.getProperty("azure.account.key"); String currContainerStr = mainProperties.getProperty("azure.test0001.container.name"); Init(currAccountStr, currKey, currContainerStr); } public SimpleShell(String accnt, String key, String cont) throws FileSystemException, IOException { Init(accnt, key, cont); } private void Init(String accnt, String key, String cont) throws IOException { conReader = new ConsoleReader(); conReader.setPrompt("AzureShell> "); List<Completer> completors = new LinkedList<>(); String currFileNameStr = "dir1"; AzFileProvider azfp = new AzFileProvider(); StaticUserAuthenticator auth = new StaticUserAuthenticator("", accnt, key); AzFileSystemConfigBuilder.getInstance().setUserAuthenticator(azfp.getDefaultFileSystemOptions(), auth); DefaultFileSystemManager currMan = new DefaultFileSystemManager(); currMan.addProvider(AzConstants.AZSBSCHEME, azfp); currMan.addProvider("file", new DefaultLocalFileProvider()); currMan.init(); mgr = currMan; //cwd = mgr.resolveFile(System.getProperty("user.dir"));c String currAzURL = String.format("%s://%s/%s/%s", AzConstants.AZSBSCHEME, accnt, cont, currFileNameStr); cwd = mgr.resolveFile(currAzURL); completors.add(new FileNameCompleter()); completors.add(new StringsCompleter(AzConstants.AZSBSCHEME, "file://", currAzURL)); AggregateCompleter aggComp = new AggregateCompleter(completors); ArgumentCompleter argComp = new ArgumentCompleter(aggComp); argComp.setStrict(false); conReader.addCompleter(argComp); Path histPath = Paths.get(System.getProperty("user.home"), ".simpleshellhist"); File histFile = histPath.toFile(); FileHistory fh = new FileHistory(histFile); conReader.setHistory(fh); conReader.setHistoryEnabled(true); Runtime.getRuntime().addShutdownHook(new Thread() { @Override public void run() { try { ((FileHistory) conReader.getHistory()).flush(); } catch (IOException ex) { log.error("Error saving history", ex); } } }); } public void go() throws Exception { String line; PrintWriter out = new PrintWriter(conReader.getOutput()); while ((line = conReader.readLine()) != null) { out.println("======>\"" + line + "\""); out.flush(); if (line.equalsIgnoreCase("quit") || line.equalsIgnoreCase("exit")) { break; } if (line.equalsIgnoreCase("clear")) { conReader.clearScreen(); continue; } try { StringTokenizer tokens = new StringTokenizer(line); ArrayList<String> cmdList = new ArrayList<>(); while (tokens.hasMoreTokens()) { cmdList.add(tokens.nextToken()); } String[] cmd = cmdList.toArray(new String[cmdList.size()]); String cmdName = cmd[0].trim().toLowerCase(); switch (cmdName) { case "cat": cat(cmd); break; case "cd": cd(cmd); break; case "cp": cp(cmd); break; case "help": help(); break; case "pwd": pwd(); break; case "ls": ls(cmd); break; case "rm": rm(cmd); break; case "touch": touch(cmd); break; default: log.warn("Unknown command \"" + cmdName + "\"."); } } catch (Exception ex) { log.error("Command failed:", ex); } } } /** * Does a 'help' command. */ public void help() { System.out.println("Commands:"); System.out.println("cat <file> Displays the contents of a file."); System.out.println("cd [folder] Changes current folder."); System.out.println("cp <src> <dest> Copies a file or folder."); System.out.println("help Shows this message."); System.out.println("ls [-R] [path] Lists contents of a file or folder."); System.out.println("pwd Displays current folder."); System.out.println("rm <path> Deletes a file or folder."); System.out.println("touch <path> Sets the last-modified time of a file."); System.out.println("exit Exits this program."); System.out.println("quit Exits this program."); } /** * Does an 'rm' command. * @param cmd * @throws java.lang.Exception */ public void rm(final String[] cmd) throws Exception { if (cmd.length < 2) { throw new Exception("USAGE: rm <path>"); } final FileObject file = mgr.resolveFile(cwd, cmd[1]); file.delete(Selectors.SELECT_SELF); } /** * Does a 'cp' command. * * @param cmd * @throws SimpleShellException */ public void cp(String[] cmd) throws SimpleShellException { if (cmd.length < 3) { throw new SimpleShellException("USAGE: cp <src> <dest>"); } FileObject src = null; try { src = mgr.resolveFile(cwd, cmd[1]); } catch (FileSystemException ex) { String errMsg = String.format("Error resolving source file '%s'", cmd[1]); //log.error( errMsg, ex); throw new SimpleShellException(errMsg, ex); } FileObject dest = null; try { dest = mgr.resolveFile(cwd, cmd[2]); } catch (FileSystemException ex) { String errMsg = String.format("Error resolving destination file '%s'", cmd[2]); //log.error( errMsg, ex); throw new SimpleShellException(errMsg, ex); } try { if (dest.exists() && dest.getType() == FileType.FOLDER) { dest = dest.resolveFile(src.getName().getBaseName()); } } catch (FileSystemException ex) { String errMsg = String.format("Error resolving folder '%s'", cmd[2]); //log.error( errMsg, ex); throw new SimpleShellException(errMsg, ex); } try { dest.copyFrom(src, Selectors.SELECT_ALL); } catch (FileSystemException ex) { String errMsg = String.format("Error copyFrom() file '%s' to '%s'", cmd[1], cmd[2]); //log.error( errMsg, ex); throw new SimpleShellException(errMsg, ex); } } /** * Does a 'cat' command. * * @param cmd * @throws SimpleShellException */ public void cat(String[] cmd) throws SimpleShellException { if (cmd.length < 2) { throw new SimpleShellException("USAGE: cat <path>"); } // Locate the file FileObject file; try { file = mgr.resolveFile(cwd, cmd[1]); } catch (FileSystemException ex) { String errMsg = String.format("Error resolving file '%s'", cmd[1]); //log.error( errMsg, ex); throw new SimpleShellException(errMsg, ex); } try { if (file.exists() == false) { // Can't cat a file that doesn't exist System.out.println(String.format("File '%s' does not exist", cmd[1])); return; } } catch (FileSystemException ex) { String errMsg = String.format("Error exists() on file '%s'", cmd[1]); //log.error( errMsg, ex); throw new SimpleShellException(errMsg, ex); } try { if (file.getType() != FileType.FILE) { // Only cat files System.out.println(String.format("File '%s' is not an actual file.", cmd[1])); return; } } catch (FileSystemException ex) { String errMsg = String.format("Error getType() on file '%s'", cmd[1]); //log.error( errMsg, ex); throw new SimpleShellException(errMsg, ex); } try { // Dump the contents to System.out FileUtil.writeContent(file, System.out); } catch (IOException ex) { String errMsg = String.format("Error WriteContent() on file '%s'", cmd[1]); //log.error( errMsg, ex); throw new SimpleShellException(errMsg, ex); } System.out.println(); } /** * Does a 'pwd' command. */ public void pwd() { System.out.println("Current folder is " + cwd.getName()); } /** * Does a 'cd' command. * If the taget directory does not exist, a message is printed to <code>System.err</code>. */ public void cd(final String[] cmd) throws Exception { final String path; if (cmd.length > 1) { path = cmd[1]; } else { path = System.getProperty("user.home"); } // Locate and validate the folder FileObject tmp = mgr.resolveFile(cwd, path); if (tmp.exists()) { cwd = tmp; } else { System.out.println("Folder does not exist: " + tmp.getName()); } System.out.println("Current folder is " + cwd.getName()); } /** * Does an 'ls' command. * * @param cmd * @throws org.apache.commons.vfs2.FileSystemException */ public void ls(final String[] cmd) throws FileSystemException { int pos = 1; final boolean recursive; if (cmd.length > pos && cmd[pos].equals("-R")) { recursive = true; pos++; } else { recursive = false; } final FileObject file; if (cmd.length > pos) { file = mgr.resolveFile(cwd, cmd[pos]); } else { file = cwd; } switch (file.getType()) { case FOLDER: // List the contents System.out.println("Contents of " + file.getName()); listChildren(file, recursive, ""); break; case FILE: // Stat the file System.out.println(file.getName()); final FileContent content = file.getContent(); System.out.println("Size: " + content.getSize() + " bytes."); final DateFormat dateFormat = DateFormat.getDateTimeInstance(DateFormat.MEDIUM, DateFormat.MEDIUM); final String lastMod = dateFormat.format(new Date(content.getLastModifiedTime())); System.out.println("Last modified: " + lastMod); break; case IMAGINARY: System.out.println(String.format("File '%s' is IMAGINARY", file.getName())); break; default: log.error(String.format("Unkown type '%d' on '%s'", file.getType(), file.getName())); break; } } /** * Does a 'touch' command. * * @param cmd * @throws java.lang.Exception */ public void touch(final String[] cmd) throws Exception { if (cmd.length < 2) { throw new Exception("USAGE: touch <path>"); } final FileObject file = mgr.resolveFile(cwd, cmd[1]); if (!file.exists()) { file.createFile(); } file.getContent().setLastModifiedTime(System.currentTimeMillis()); } /** * Lists the children of a folder. */ public void listChildren(final FileObject dir, final boolean recursive, final String prefix) throws FileSystemException { final FileObject[] children = dir.getChildren(); for (int i = 0; i < children.length; i++) { final FileObject child = children[i]; System.out.print(prefix); System.out.print(child.getName().getBaseName()); if (child.getType() == FileType.FOLDER) { System.out.println("/"); if (recursive) { listChildren(child, recursive, prefix + " "); } } else { System.out.println(); } } } }