1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache license, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the license for the specific language governing permissions and
15 * limitations under the license.
16 */
17 package org.apache.logging.log4j.core.appender.db.jpa.converter;
18
19 import java.util.Map;
20
21 import javax.persistence.AttributeConverter;
22 import javax.persistence.Converter;
23
24 /**
25 * A JPA 2.1 attribute converter for {@link Map Map<String, String>}s in
26 * {@link org.apache.logging.log4j.core.LogEvent}s. This converter is only capable of converting to {@link String}s. The
27 * {@link #convertToEntityAttribute(String)} method throws an {@link UnsupportedOperationException}. If you need to
28 * support converting to an entity attribute, you should use the {@link ContextMapJsonAttributeConverter} for conversion
29 * both ways.
30 */
31 @Converter(autoApply = false)
32 public class ContextMapAttributeConverter implements AttributeConverter<Map<String, String>, String> {
33 @Override
34 public String convertToDatabaseColumn(final Map<String, String> contextMap) {
35 if (contextMap == null) {
36 return null;
37 }
38
39 return contextMap.toString();
40 }
41
42 @Override
43 public Map<String, String> convertToEntityAttribute(final String s) {
44 throw new UnsupportedOperationException("Log events can only be persisted, not extracted.");
45 }
46 }