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 org.apache.sshd.git.pgm; import java.io.File; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.io.PrintWriter; import java.lang.reflect.Field; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.text.MessageFormat; import java.util.ArrayList; import java.util.List; import org.eclipse.jgit.api.Git; import org.eclipse.jgit.lib.Repository; import org.eclipse.jgit.pgm.CommandCatalog; import org.eclipse.jgit.pgm.CommandRef; import org.eclipse.jgit.pgm.Die; import org.eclipse.jgit.pgm.TextBuiltin; import org.eclipse.jgit.pgm.internal.CLIText; import org.eclipse.jgit.pgm.opt.CmdLineParser; import org.eclipse.jgit.pgm.opt.SubcommandHandler; import org.eclipse.jgit.util.io.ThrowingPrintWriter; import org.kohsuke.args4j.Argument; import org.kohsuke.args4j.CmdLineException; import org.kohsuke.args4j.ExampleMode; import org.kohsuke.args4j.Option; /** * TODO Add javadoc * * @author <a href="mailto:dev@mina.apache.org">Apache MINA SSHD Project</a> */ public class EmbeddedCommandRunner { @Option(name = "--help", usage = "usage_displayThisHelpText", aliases = { "-h" }) private boolean help; @Option(name = "--show-stack-trace", usage = "usage_displayThejavaStackTraceOnExceptions") private boolean showStackTrace; @Option(name = "--git-dir", metaVar = "metaVar_gitDir", usage = "usage_setTheGitRepositoryToOperateOn") private String gitdir; @Argument(index = 0, metaVar = "metaVar_command", required = true, handler = SubcommandHandler.class) private TextBuiltin subcommand; @Argument(index = 1, metaVar = "metaVar_arg") private List<String> arguments = new ArrayList<>(); private String rootDir; public EmbeddedCommandRunner(String rootDir) { this.rootDir = rootDir; } /** * Execute a command. * * @param argv * the command and its arguments * @param in * the input stream, may be null in which case the system input stream will be used * @param out * the output stream, may be null in which case the system output stream will be used * @param err * the error stream, may be null in which case the system error stream will be used * @throws Exception * if an error occurs */ public void execute(final String[] argv, InputStream in, OutputStream out, OutputStream err) throws Exception { final CmdLineParser clp = new CmdLineParser(this); PrintWriter writer = new PrintWriter(err != null ? err : System.err); try { clp.parseArgument(argv); } catch (CmdLineException e) { if (argv.length > 0 && !help) { writer.println(MessageFormat.format(CLIText.get().fatalError, e.getMessage())); writer.flush(); throw new Die(true); } } if (argv.length == 0 || help) { final String ex = clp.printExample(ExampleMode.ALL, CLIText.get().resourceBundle()); writer.println("jgit" + ex + " command [ARG ...]"); //$NON-NLS-1$ if (help) { writer.println(); clp.printUsage(writer, CLIText.get().resourceBundle()); writer.println(); } else if (subcommand == null) { writer.println(); writer.println(CLIText.get().mostCommonlyUsedCommandsAre); final CommandRef[] common = CommandCatalog.common(); int width = 0; for (final CommandRef c : common) { width = Math.max(width, c.getName().length()); } width += 2; for (final CommandRef c : common) { writer.print(' '); writer.print(c.getName()); for (int i = c.getName().length(); i < width; i++) { writer.print(' '); } writer.print(CLIText.get().resourceBundle().getString(c.getUsage())); writer.println(); } writer.println(); } writer.flush(); throw new Die(true); } gitdir = new File(rootDir, gitdir).getPath(); final TextBuiltin cmd = subcommand; // cmd.ins = in; // cmd.outs = out; // cmd.errs = err; // if (cmd.requiresRepository()) // cmd.init(openGitDir(gitdir), null); // else // cmd.init(null, gitdir); // try { // cmd.execute(arguments.toArray(new String[arguments.size()])); // } finally { // if (cmd.outw != null) // cmd.outw.flush(); // if (cmd.errw != null) // cmd.errw.flush(); // } set(cmd, "ins", in); set(cmd, "outs", out); set(cmd, "errs", err); Boolean success = (Boolean) call(cmd, "requiresRepository"); if (success) { call(cmd, "init", new Class[] { Repository.class, String.class }, new Object[] { openGitDir(gitdir), gitdir }); } else { call(cmd, "init", new Class[] { Repository.class, String.class }, new Object[] { null, gitdir }); } try { cmd.execute(arguments.toArray(new String[arguments.size()])); } finally { if (get(cmd, "outw") != null) { ((ThrowingPrintWriter) get(cmd, "outw")).flush(); } if (get(cmd, "errw") != null) { ((ThrowingPrintWriter) get(cmd, "errw")).flush(); } } } private Object get(Object obj, String name) throws IllegalAccessException, NoSuchFieldException { Class<?> clazz = obj.getClass(); while (clazz != null) { try { Field field = clazz.getDeclaredField(name); field.setAccessible(true); return field.get(obj); } catch (NoSuchFieldException e) { clazz = clazz.getSuperclass(); } } throw new NoSuchFieldException(name); } private void set(Object obj, String name, Object val) throws IllegalAccessException, NoSuchFieldException { Class<?> clazz = obj.getClass(); while (clazz != null) { try { Field field = clazz.getDeclaredField(name); field.setAccessible(true); field.set(obj, val); return; } catch (NoSuchFieldException e) { clazz = clazz.getSuperclass(); } } throw new NoSuchFieldException(name); } private Object call(Object obj, String name) throws NoSuchMethodException, InvocationTargetException, IllegalAccessException { return call(obj, name, new Class[0], new Object[0]); } private Object call(Object obj, String name, Class<?>[] types, Object[] args) throws NoSuchMethodException, InvocationTargetException, IllegalAccessException { Class<?> clazz = obj.getClass(); while (clazz != null) { try { Method method = clazz.getDeclaredMethod(name, types); method.setAccessible(true); return method.invoke(obj, args); } catch (NoSuchMethodException e) { clazz = clazz.getSuperclass(); } } throw new NoSuchMethodException(name); } /** * Evaluate the {@code --git-dir} option and open the repository. * * @param gitdir * the {@code --git-dir} option given on the command line. May be * null if it was not supplied. * @return the repository to operate on. * @throws IOException * the repository cannot be opened. */ protected Repository openGitDir(String gitdir) throws IOException { return Git.open(new File(gitdir)).getRepository(); /* RepositoryBuilder rb = new RepositoryBuilder() // .setGitDir(gitdir != null ? new File(gitdir) : null) // .readEnvironment() // .findGitDir(); if (rb.getGitDir() == null) throw new Die(CLIText.get().cantFindGitDirectory); return rb.build(); */ } }