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    package org.apache.logging.log4j.message;
018    
019    import java.io.IOException;
020    import java.io.ObjectInputStream;
021    import java.io.ObjectOutputStream;
022    import java.text.Format;
023    import java.text.MessageFormat;
024    import java.util.Arrays;
025    import java.util.regex.Pattern;
026    
027    /**
028     * Handles messages that contain a format String. Dynamically determines if the format conforms to
029     * MessageFormat or String.format and if not then uses ParameterizedMessage to format.
030     */
031    public class FormattedMessage implements Message {
032    
033        private static final long serialVersionUID = -665975803997290697L;
034        private static final int HASHVAL = 31;
035        private static final String FORMAT_SPECIFIER = "%(\\d+\\$)?([-#+ 0,(\\<]*)?(\\d+)?(\\.\\d+)?([tT])?([a-zA-Z%])";
036        private static final Pattern MSG_PATTERN = Pattern.compile(FORMAT_SPECIFIER);
037    
038        private String messagePattern;
039        private transient Object[] argArray;
040        private String[] stringArgs;
041        private transient String formattedMessage;
042        private final Throwable throwable;
043        private Message message;
044    
045        public FormattedMessage(final String messagePattern, final Object[] arguments, final Throwable throwable) {
046            this.messagePattern = messagePattern;
047            this.argArray = arguments;
048            this.throwable = throwable;
049        }
050    
051        public FormattedMessage(final String messagePattern, final Object[] arguments) {
052            this(messagePattern, arguments, null);
053        }
054    
055        /**
056         * Constructor with a pattern and a single parameter.
057         * @param messagePattern The message pattern.
058         * @param arg The parameter.
059         */
060        public FormattedMessage(final String messagePattern, final Object arg) {
061            this(messagePattern, new Object[] {arg}, null);
062        }
063    
064        /**
065         * Constructor with a pattern and two parameters.
066         * @param messagePattern The message pattern.
067         * @param arg1 The first parameter.
068         * @param arg2 The second parameter.
069         */
070        public FormattedMessage(final String messagePattern, final Object arg1, final Object arg2) {
071            this(messagePattern, new Object[]{arg1, arg2});
072        }
073    
074    
075        /**
076         * Returns the formatted message.
077         * @return the formatted message.
078         */
079        @Override
080        public String getFormattedMessage() {
081            if (formattedMessage == null) {
082                if (message == null) {
083                    message = getMessage(messagePattern, argArray, throwable);
084                }
085                formattedMessage = message.getFormattedMessage();
086            }
087            return formattedMessage;
088        }
089    
090        /**
091         * Returns the message pattern.
092         * @return the message pattern.
093         */
094        @Override
095        public String getFormat() {
096            return messagePattern;
097        }
098    
099        /**
100         * Returns the message parameters.
101         * @return the message parameters.
102         */
103        @Override
104        public Object[] getParameters() {
105            if (argArray != null) {
106                return argArray;
107            }
108            return stringArgs;
109        }
110    
111        protected Message getMessage(final String msgPattern, final Object[] args, final Throwable throwable) {
112            try {
113                final MessageFormat format = new MessageFormat(msgPattern);
114                final Format[] formats = format.getFormats();
115                if (formats != null && formats.length > 0) {
116                    return new MessageFormatMessage(msgPattern, args);
117                }
118            } catch (final Exception ignored) {
119                // Obviously, the message is not a proper pattern for MessageFormat.
120            }
121            try {
122                if (MSG_PATTERN.matcher(msgPattern).find()) {
123                    return new StringFormattedMessage(msgPattern, args);
124                }
125            } catch (final Exception ignored) {
126                // Also not properly formatted.
127            }
128            return new ParameterizedMessage(msgPattern, args, throwable);
129        }
130    
131        @Override
132        public boolean equals(final Object o) {
133            if (this == o) {
134                return true;
135            }
136            if (o == null || getClass() != o.getClass()) {
137                return false;
138            }
139    
140            final FormattedMessage that = (FormattedMessage) o;
141    
142            if (messagePattern != null ? !messagePattern.equals(that.messagePattern) : that.messagePattern != null) {
143                return false;
144            }
145            if (!Arrays.equals(stringArgs, that.stringArgs)) {
146                return false;
147            }
148    
149            return true;
150        }
151    
152        @Override
153        public int hashCode() {
154            int result = messagePattern != null ? messagePattern.hashCode() : 0;
155            result = HASHVAL * result + (stringArgs != null ? Arrays.hashCode(stringArgs) : 0);
156            return result;
157        }
158    
159    
160        @Override
161        public String toString() {
162            return "FormattedMessage[messagePattern=" + messagePattern + ", args=" +
163                Arrays.toString(argArray) + ']';
164        }
165    
166        private void writeObject(final ObjectOutputStream out) throws IOException {
167            out.defaultWriteObject();
168            getFormattedMessage();
169            out.writeUTF(formattedMessage);
170            out.writeUTF(messagePattern);
171            out.writeInt(argArray.length);
172            stringArgs = new String[argArray.length];
173            int i = 0;
174            for (final Object obj : argArray) {
175                stringArgs[i] = obj.toString();
176                ++i;
177            }
178        }
179    
180        private void readObject(final ObjectInputStream in) throws IOException, ClassNotFoundException {
181            in.defaultReadObject();
182            formattedMessage = in.readUTF();
183            messagePattern = in.readUTF();
184            final int length = in.readInt();
185            stringArgs = new String[length];
186            for (int i = 0; i < length; ++i) {
187                stringArgs[i] = in.readUTF();
188            }
189        }
190    
191        /**
192         * Always returns null.
193         *
194         * @return null
195         */
196        @Override
197        public Throwable getThrowable() {
198            if (throwable != null) {
199                return throwable;
200            }
201            if (message == null) {
202                message = getMessage(messagePattern, argArray, null);
203            }
204            return message.getThrowable();
205        }
206    }