001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *   http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 *
017 */
018
019package org.apache.commons.net.examples;
020
021import java.io.InputStream;
022import java.lang.reflect.InvocationTargetException;
023import java.lang.reflect.Method;
024import java.security.CodeSource;
025import java.util.Collections;
026import java.util.List;
027import java.util.Properties;
028
029/**
030 * Helper application for example classes.
031 */
032public class Main {
033
034    private static boolean fromJar() {
035        final CodeSource codeSource = Main.class.getProtectionDomain().getCodeSource();
036        if (codeSource != null) {
037            return codeSource.getLocation().getFile().endsWith(".jar");
038        }
039        return false; // No idea if this can happen
040    }
041
042    /**
043     * Helper application for example classes. Lists available classes, and provides shorthand invocation. For example:<br>
044     * <code>java -jar commons-net-examples-m.n.jar FTPClientExample -l host user password</code>
045     *
046     * @param args the first argument is used to name the class; remaining arguments are passed to the target class.
047     * @throws Throwable if an error occurs
048     */
049    public static void main(final String[] args) throws Throwable {
050        final Properties fp = new Properties();
051        final InputStream ras = Main.class.getResourceAsStream("examples.properties");
052        if (ras != null) {
053            fp.load(ras);
054        } else {
055            System.err.println("[Cannot find examples.properties file, so aliases cannot be used]");
056        }
057        if (args.length == 0) {
058            if (Thread.currentThread().getStackTrace().length > 2) { // called by Maven
059                System.out.println(
060                        "Usage: mvn -q exec:java  -Dexec.arguments=<alias or" + " exampleClass>,<exampleClass parameters> (comma-separated, no spaces)");
061                System.out.println("Or   : mvn -q exec:java  -Dexec.args=\"<alias" + " or exampleClass> <exampleClass parameters>\" (space separated)");
062            } else if (fromJar()) {
063                System.out.println("Usage: java -jar commons-net-examples-m.n.jar <alias or exampleClass> <exampleClass parameters>");
064            } else {
065                System.out
066                        .println("Usage: java -cp target/classes org.apache.commons.net.examples.Main" + " <alias or exampleClass> <exampleClass parameters>");
067            }
068            @SuppressWarnings("unchecked") // property names are Strings
069            final List<String> l = (List<String>) Collections.list(fp.propertyNames());
070            if (l.isEmpty()) {
071                return;
072            }
073            l.sort(null);
074            System.out.println("\nAliases and their classes:");
075            for (final String s : l) {
076                System.out.printf("%-25s %s%n", s, fp.getProperty(s));
077            }
078            return;
079        }
080
081        final String shortName = args[0];
082        String fullName = fp.getProperty(shortName);
083        if (fullName == null) {
084            fullName = shortName;
085        }
086        try {
087            final Class<?> clazz = Class.forName(fullName);
088            final Method m = clazz.getDeclaredMethod("main", args.getClass());
089            final String[] args2 = new String[args.length - 1];
090            System.arraycopy(args, 1, args2, 0, args2.length);
091            try {
092                m.invoke(null, (Object) args2);
093            } catch (final InvocationTargetException ite) {
094                final Throwable cause = ite.getCause();
095                if (cause != null) {
096                    throw cause;
097                }
098                throw ite;
099            }
100        } catch (final ClassNotFoundException e) {
101            System.out.println(e);
102        }
103    }
104}