001 /*
002 * Copyright (C) 2012 eXo Platform SAS.
003 *
004 * This is free software; you can redistribute it and/or modify it
005 * under the terms of the GNU Lesser General Public License as
006 * published by the Free Software Foundation; either version 2.1 of
007 * the License, or (at your option) any later version.
008 *
009 * This software is distributed in the hope that it will be useful,
010 * but WITHOUT ANY WARRANTY; without even the implied warranty of
011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
012 * Lesser General Public License for more details.
013 *
014 * You should have received a copy of the GNU Lesser General Public
015 * License along with this software; if not, write to the Free
016 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
017 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
018 */
019
020 package org.crsh.cli.type;
021
022 import org.crsh.cli.completers.EmptyCompleter;
023 import org.crsh.cli.completers.EnumCompleter;
024 import org.crsh.cli.completers.FileCompleter;
025 import org.crsh.cli.completers.ObjectNameCompleter;
026 import org.crsh.cli.completers.ThreadCompleter;
027 import org.crsh.cli.spi.Completer;
028
029 import javax.management.ObjectName;
030 import java.io.File;
031 import java.util.Properties;
032 import java.util.StringTokenizer;
033
034 /**
035 * Defines a type for values, this is used for transforming a textual value into a type, for command
036 * argument and options. A value type defines:
037 *
038 * <ul>
039 * <li>The generic value type that is converted to.</li>
040 * <li>The implementation of the {@link #parse(Class, String)} method that transforms the string into a value.</li>
041 * <li>An optional completer.</li>
042 * </ul>
043 *
044 * @param <V> the generic value type
045 */
046 public abstract class ValueType<V> {
047
048 /** Identity. */
049 public static final ValueType<String> STRING = new ValueType<String>(String.class) {
050 @Override
051 public <S extends String> S parse(Class<S> type, String s) throws Exception {
052 return type.cast(s);
053 }
054 };
055
056 /** Integer. */
057 public static final ValueType<Integer> INTEGER = new ValueType<Integer>(Integer.class) {
058 @Override
059 public <S extends Integer> S parse(Class<S> type, String s) throws Exception {
060 return type.cast(Integer.parseInt(s));
061 }
062 };
063
064 /** Boolean. */
065 public static final ValueType<Boolean> BOOLEAN = new ValueType<Boolean>(Boolean.class) {
066 @Override
067 public <S extends Boolean> S parse(Class<S> type, String s) throws Exception {
068 return type.cast(Boolean.parseBoolean(s));
069 }
070 };
071
072 /** Any Java enum. */
073 public static final ValueType<Enum> ENUM = new ValueType<Enum>(Enum.class, EnumCompleter.class) {
074 @Override
075 public <S extends Enum> S parse(Class<S> type, String s) {
076 // We cannot express S extends Enum<S> type
077 // so we need this necessary cast to make the java compiler happy
078 S s1 = (S)Enum.valueOf(type, s);
079 return s1;
080 }
081 };
082
083 /** Properties as semi colon separated values. */
084 public static final ValueType<Properties> PROPERTIES = new ValueType<Properties>(Properties.class) {
085 @Override
086 public <S extends Properties> S parse(Class<S> type, String s) throws Exception {
087 java.util.Properties props = new java.util.Properties();
088 StringTokenizer tokenizer = new StringTokenizer(s, ";", false);
089 while(tokenizer.hasMoreTokens()){
090 String token = tokenizer.nextToken();
091 if(token.contains("=")) {
092 String key = token.substring(0, token.indexOf('='));
093 String value = token.substring(token.indexOf('=') + 1, token.length());
094 props.put(key, value);
095 }
096 }
097 return type.cast(props);
098 }
099 };
100
101 /** A JMX object name value type. */
102 public static final ValueType<ObjectName> OBJECT_NAME = new ValueType<ObjectName>(ObjectName.class, ObjectNameCompleter.class) {
103 @Override
104 public <S extends ObjectName> S parse(Class<S> type, String s) throws Exception {
105 return type.cast(ObjectName.getInstance(s));
106 }
107 };
108
109 /** A value type for threads. */
110 public static final ValueType<Thread> THREAD = new ValueType<Thread>(Thread.class, ThreadCompleter.class) {
111 @Override
112 public <S extends Thread> S parse(Class<S> type, String s) throws Exception {
113 long id = Long.parseLong(s);
114 for (Thread t : Thread.getAllStackTraces().keySet()) {
115 if (t.getId() == id) {
116 return type.cast(t);
117 }
118 }
119 throw new IllegalArgumentException("No thread " + s );
120 }
121 };
122
123 /** A value type for files. */
124 public static final ValueType<File> FILE = new ValueType<File>(File.class, FileCompleter.class) {
125 @Override
126 public <S extends File> S parse(Class<S> type, String s) throws Exception {
127 return type.cast(new File(s));
128 }
129 };
130
131 /** . */
132 protected final Class<V> type;
133
134 /** . */
135 protected final Class<? extends Completer> completer;
136
137 protected ValueType(Class<V> type, Class<? extends Completer> completer) throws NullPointerException {
138 if (type == null) {
139 throw new NullPointerException("No null value type accepted");
140 }
141 if (completer == null) {
142 throw new NullPointerException("No null completer accepted");
143 }
144
145 //
146 this.completer = completer;
147 this.type = type;
148 }
149
150 protected ValueType(Class<V> type) throws NullPointerException {
151 if (type == null) {
152 throw new NullPointerException("No null value type accepted");
153 }
154
155 //
156 this.completer = EmptyCompleter.class;
157 this.type = type;
158 }
159
160 final int getDistance(Class<?> clazz) {
161 if (type == clazz) {
162 return 0;
163 } else if (type.isAssignableFrom(clazz)) {
164 int degree = 0;
165 for (Class<?> current = clazz;current != type;current = current.getSuperclass()) {
166 degree++;
167 }
168 return degree;
169 } else {
170 return -1;
171 }
172 }
173
174 @Override
175 public final int hashCode() {
176 return type.hashCode();
177 }
178
179 @Override
180 public final boolean equals(Object obj) {
181 if (obj == null) {
182 return false;
183 } else {
184 if (obj == this) {
185 return true;
186 } else {
187 if (obj.getClass() == ValueType.class) {
188 ValueType that = (ValueType)obj;
189 return type == that.type;
190 } else {
191 return false;
192 }
193 }
194 }
195 }
196
197 public Class<? extends Completer> getCompleter() {
198 return completer;
199 }
200
201 public final Class<V> getType() {
202 return type;
203 }
204
205 public final V parse(String s) throws Exception {
206 return parse(type, s);
207 }
208
209 /**
210 * Parse the <code>s</code> argument into a value of type S that is a subclass of the
211 * generic value type V.
212 *
213 * @param type the target type of the value
214 * @param s the string to convert
215 * @param <S> the generic type of the converted value
216 * @return the converted value
217 * @throws Exception any exception that would prevent the conversion to happen
218 */
219 public abstract <S extends V> S parse(Class<S> type, String s) throws Exception;
220
221 }