| /** |
| * 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.rya.shell.util; |
| |
| import static java.util.Objects.requireNonNull; |
| |
| import java.io.IOException; |
| import java.util.Set; |
| |
| import org.springframework.beans.factory.annotation.Autowired; |
| import org.springframework.security.util.FieldUtils; |
| import org.springframework.shell.core.Shell; |
| |
| import com.google.common.base.Optional; |
| import com.google.common.collect.Sets; |
| |
| import edu.umd.cs.findbugs.annotations.DefaultAnnotation; |
| import edu.umd.cs.findbugs.annotations.NonNull; |
| import jline.console.ConsoleReader; |
| |
| /** |
| * Provides access to the host {@link Shell}'s {@link ConsoleReader} and some |
| * utility functions for using it. |
| */ |
| @DefaultAnnotation(NonNull.class) |
| public abstract class JLinePrompt { |
| |
| /** |
| * Defines things that may be typed in response to a boolean prompt that evaluate to true. |
| */ |
| private static final Set<String> affirmativeStrings = Sets.newHashSet("true", "t", "yes", "y"); |
| |
| /** |
| * Defines things that may be typed in response to a boolean prompt that evaluate to false. |
| */ |
| private static final Set<String> negativeStrings = Sets.newHashSet("false", "f", "no", "n"); |
| |
| @Autowired |
| private Shell shell; |
| |
| /** |
| * @return The shell's {@link ConsoleReader}. |
| */ |
| public ConsoleReader getReader() { |
| // XXX Spring Shell doesn't expose the reader that we need to use to |
| // read values from a terminal, so use reflection to pull it out. |
| return (ConsoleReader) FieldUtils.getProtectedFieldValue("reader", shell); |
| } |
| |
| /** |
| * Formats a prompt that shows a default value. |
| * |
| * @param fieldName - The text portion that appears before the default. (not null) |
| * @param defaultValue - The default value that will be shown in the prompt. |
| * @return A prompt that shows the default value for a field. |
| */ |
| public String makeFieldPrompt(final String fieldName, final boolean defaultValue) { |
| return makeFieldPrompt(fieldName, Boolean.toString(defaultValue)); |
| } |
| |
| /** |
| * Formats a prompt that shows a default value. |
| * |
| * @param fieldName - The text portion that appears before the default. (not null) |
| * @param defaultValue - The default value that will be shown in the prompt. |
| * @return A prompt that shows the default value for a field. |
| */ |
| public String makeFieldPrompt(final String fieldName, final String defaultValue) { |
| return String.format("%s [default: %s]: ", fieldName, defaultValue); |
| } |
| |
| /** |
| * Checks if a user's input matches one of the affirmative strings. |
| * |
| * @param input - The user's input. (not null) |
| * @return {@code true} if the input is one of the affirmative values; otherwise {@code false}. |
| */ |
| private boolean isAffirmative(final String input) { |
| requireNonNull(input); |
| for(final String affirmativeString : affirmativeStrings) { |
| if( input.equalsIgnoreCase(affirmativeString) ) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Checks if a user's input matches one of the negative strings. |
| * |
| * @param input - The user's input. (not null) |
| * @return {@code true} if the input is one of the negative values; otherwise {@code false}. |
| */ |
| private boolean isNegative(final String input) { |
| requireNonNull(input); |
| for(final String negativeString : negativeStrings) { |
| if( input.equalsIgnoreCase(negativeString) ) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Prompts a user for a boolean value. The prompt will be repeated until |
| * a value true/false string has been submitted. If a default value is |
| * provided, then it will be used if the user doens't enter anything. |
| * |
| * @param prompt - The prompt for the input. (not null) |
| * @param defaultValue - The default value for the input if one is provided. (not null) |
| * @return The value the user entered. |
| * @throws IOException There was a problem reading values from the user. |
| */ |
| protected boolean promptBoolean(final String prompt, final Optional<Boolean> defaultValue) throws IOException { |
| requireNonNull(prompt); |
| requireNonNull(defaultValue); |
| |
| final ConsoleReader reader = getReader(); |
| reader.setPrompt(prompt); |
| |
| Boolean value = null; |
| boolean prompting = true; |
| |
| while(prompting) { |
| // An empty input means to use the default value. |
| final String input = reader.readLine(); |
| if(input.isEmpty() && defaultValue.isPresent()) { |
| value = defaultValue.get(); |
| prompting = false; |
| } |
| |
| // Check if it is one of the affirmative answers. |
| if(isAffirmative(input)) { |
| value = true; |
| prompting = false; |
| } |
| |
| // Check if it is one of the negative answers. |
| if(isNegative(input)) { |
| value = false; |
| prompting = false; |
| } |
| |
| // If we are still prompting, the input was invalid. |
| if(prompting) { |
| reader.println("Invalid response (true/false)"); |
| } |
| } |
| |
| return value; |
| } |
| |
| /** |
| * Prompts a user for a String value. The prompt will be repeated until a |
| * value has been submitted. If a default value is provided, then it will be |
| * used if the user doesn't enter anything. |
| * |
| * @param prompt - The prompt for the input. (not null) |
| * @param defaultValue - The default value for the input if one is provided. (not null) |
| * @return The value the user entered. |
| * @throws IOException There was a problem reading values from the user. |
| */ |
| protected String promptString(final String prompt, final Optional<String> defaultValue) throws IOException { |
| requireNonNull(prompt); |
| requireNonNull(defaultValue); |
| |
| final ConsoleReader reader = getReader(); |
| reader.setPrompt(prompt); |
| |
| String value = null; |
| boolean prompting = true; |
| |
| while(prompting) { |
| // Read a line of input. |
| final String input = reader.readLine(); |
| |
| if(!input.isEmpty()) { |
| // If a value was provided, return it. |
| value = input; |
| prompting = false; |
| } else { |
| // Otherwise, if a default value was provided, return it; |
| if(defaultValue.isPresent()) { |
| value = defaultValue.get(); |
| prompting = false; |
| } else { |
| // Otherwise, the user must provide a value. |
| reader.println("Invalid response. Must provide a value."); |
| } |
| } |
| } |
| |
| return value; |
| } |
| } |