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.appender.db.jpa.converter; 018 019 import java.io.IOException; 020 import java.util.Map; 021 import javax.persistence.AttributeConverter; 022 import javax.persistence.PersistenceException; 023 024 import com.fasterxml.jackson.core.type.TypeReference; 025 import com.fasterxml.jackson.databind.ObjectMapper; 026 027 /** 028 * A JPA 2.1 attribute converter for {@link Map Map<String, String>}s in 029 * {@link org.apache.logging.log4j.core.LogEvent}s. This converter is capable of converting both to and from 030 * {@link String}s. 031 * 032 * In addition to other optional dependencies required by the JPA appender, this converter requires the Jackson Data 033 * Processor. 034 */ 035 public class ContextMapJsonAttributeConverter implements AttributeConverter<Map<String, String>, String> { 036 static final ObjectMapper OBJECT_MAPPER = new ObjectMapper(); 037 038 @Override 039 public String convertToDatabaseColumn(final Map<String, String> contextMap) { 040 try { 041 return OBJECT_MAPPER.writeValueAsString(contextMap); 042 } catch (IOException e) { 043 throw new PersistenceException("Failed to convert map to JSON string.", e); 044 } 045 } 046 047 @Override 048 public Map<String, String> convertToEntityAttribute(final String s) { 049 if (s == null || s.length() == 0) { 050 return null; 051 } 052 try { 053 return OBJECT_MAPPER.readValue(s, new TypeReference<Map<String, String>>() { }); 054 } catch (IOException e) { 055 throw new PersistenceException("Failed to convert JSON string to map.", e); 056 } 057 } 058 }