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.core.jackson;
018    
019    import java.io.IOException;
020    
021    import com.fasterxml.jackson.core.JsonParser;
022    import com.fasterxml.jackson.core.JsonProcessingException;
023    import com.fasterxml.jackson.core.JsonToken;
024    import com.fasterxml.jackson.databind.DeserializationContext;
025    import com.fasterxml.jackson.databind.JsonMappingException;
026    import com.fasterxml.jackson.databind.deser.std.StdScalarDeserializer;
027    
028    /**
029     * Copy and edit the Jackson (Apache License 2.0) class to use Log4j attribute names. Does not work as of Jackson 2.3.2.
030     * <p>
031     * <em>Consider this class private.</em>
032     * </p>
033     */
034    public final class Log4jStackTraceElementDeserializer extends StdScalarDeserializer<StackTraceElement> {
035        private static final long serialVersionUID = 1L;
036    
037        /**
038         * Constructs a new initialized instance.
039         */
040        public Log4jStackTraceElementDeserializer() {
041            super(StackTraceElement.class);
042        }
043    
044        @Override
045        public StackTraceElement deserialize(final JsonParser jp, final DeserializationContext ctxt) throws IOException,
046                JsonProcessingException {
047            JsonToken t = jp.getCurrentToken();
048            // Must get an Object
049            if (t == JsonToken.START_OBJECT) {
050                String className = null, methodName = null, fileName = null;
051                int lineNumber = -1;
052    
053                while ((t = jp.nextValue()) != JsonToken.END_OBJECT) {
054                    final String propName = jp.getCurrentName();
055                    if ("class".equals(propName)) {
056                        className = jp.getText();
057                    } else if ("file".equals(propName)) {
058                        fileName = jp.getText();
059                    } else if ("line".equals(propName)) {
060                        if (t.isNumeric()) {
061                            lineNumber = jp.getIntValue();
062                        } else {
063                            // An XML number always comes in a string since there is no syntax help as with JSON.
064                            try {
065                                lineNumber = Integer.parseInt(jp.getText().trim());
066                            } catch (final NumberFormatException e) {
067                                throw JsonMappingException.from(jp, "Non-numeric token (" + t + ") for property 'line'", e);
068                            }
069                        }
070                    } else if ("method".equals(propName)) {
071                        methodName = jp.getText();
072                    } else if ("nativeMethod".equals(propName)) {
073                        // no setter, not passed via constructor: ignore
074                    } else {
075                        this.handleUnknownProperty(jp, ctxt, this._valueClass, propName);
076                    }
077                }
078                return new StackTraceElement(className, methodName, fileName, lineNumber);
079            }
080            throw ctxt.mappingException(this._valueClass, t);
081        }
082    }