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.accumulo.shell.commands; import static java.nio.charset.StandardCharsets.UTF_8; import java.security.SecureRandom; import java.util.Base64; import java.util.Random; import org.apache.accumulo.shell.Shell; import org.apache.accumulo.shell.Shell.Command; import org.apache.accumulo.shell.ShellCommandException; import org.apache.accumulo.shell.ShellCommandException.ErrorCode; import org.apache.commons.cli.CommandLine; public class HiddenCommand extends Command { private static Random rand = new SecureRandom(); @Override public String description() { return "The first rule of Accumulo is: \"You don't talk about Accumulo.\""; } @Override public int execute(final String fullCommand, final CommandLine cl, final Shell shellState) throws Exception { if (rand.nextInt(10) == 0) { shellState.getReader().beep(); shellState.getReader().println(); shellState.getReader().println(new String(Base64.getDecoder().decode( "ICAgICAgIC4tLS4KICAgICAgLyAvXCBcCiAgICAgKCAvLS1cICkKICAgICAuPl8gIF88LgogICAgLyB8ICd8ICcgXAog" + "ICAvICB8Xy58Xy4gIFwKICAvIC98ICAgICAgfFwgXAogfCB8IHwgfFwvfCB8IHwgfAogfF98IHwgfCAgfCB8IHxffAogICAgIC8gIF9fICBcCiAgICAvICAv" + "ICBcICBcCiAgIC8gIC8gICAgXCAgXF8KIHwvICAvICAgICAgXCB8IHwKIHxfXy8gICAgICAgIFx8X3wK"), UTF_8)); } else { throw new ShellCommandException(ErrorCode.UNRECOGNIZED_COMMAND, getName()); } return 0; } @Override public int numArgs() { return Shell.NO_FIXED_ARG_LENGTH_CHECK; } @Override public String getName() { return "accvmvlo"; } }