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;
018
019 import java.lang.reflect.Constructor;
020
021 import org.apache.logging.log4j.core.Filter;
022 import org.apache.logging.log4j.core.LogEvent;
023 import org.apache.logging.log4j.core.appender.AbstractAppender;
024 import org.apache.logging.log4j.core.appender.db.AbstractDatabaseAppender;
025 import org.apache.logging.log4j.core.config.plugins.Plugin;
026 import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
027 import org.apache.logging.log4j.core.config.plugins.PluginElement;
028 import org.apache.logging.log4j.core.config.plugins.PluginFactory;
029 import org.apache.logging.log4j.core.util.Booleans;
030 import org.apache.logging.log4j.core.util.Loader;
031 import org.apache.logging.log4j.util.Strings;
032
033 /**
034 * This Appender writes logging events to a relational database using the Java Persistence API. It requires a
035 * pre-configured JPA persistence unit and a concrete implementation of the abstract
036 * {@link AbstractLogEventWrapperEntity} class decorated with JPA annotations.
037 *
038 * @see AbstractLogEventWrapperEntity
039 */
040 @Plugin(name = "JPA", category = "Core", elementType = "appender", printObject = true)
041 public final class JpaAppender extends AbstractDatabaseAppender<JpaDatabaseManager> {
042 private static final long serialVersionUID = 1L;
043
044 private final String description;
045
046 private JpaAppender(final String name, final Filter filter, final boolean ignoreExceptions,
047 final JpaDatabaseManager manager) {
048 super(name, filter, ignoreExceptions, manager);
049 this.description = this.getName() + "{ manager=" + this.getManager() + " }";
050 }
051
052 @Override
053 public String toString() {
054 return this.description;
055 }
056
057 /**
058 * Factory method for creating a JPA appender within the plugin manager.
059 *
060 * @param name The name of the appender.
061 * @param ignore If {@code "true"} (default) exceptions encountered when appending events are logged; otherwise
062 * they are propagated to the caller.
063 * @param filter The filter, if any, to use.
064 * @param bufferSize If an integer greater than 0, this causes the appender to buffer log events and flush whenever
065 * the buffer reaches this size.
066 * @param entityClassName The fully qualified name of the concrete {@link AbstractLogEventWrapperEntity}
067 * implementation that has JPA annotations mapping it to a database table.
068 * @param persistenceUnitName The name of the JPA persistence unit that should be used for persisting log events.
069 * @return a new JPA appender.
070 */
071 @PluginFactory
072 public static JpaAppender createAppender(
073 @PluginAttribute("name") final String name,
074 @PluginAttribute("ignoreExceptions") final String ignore,
075 @PluginElement("Filter") final Filter filter,
076 @PluginAttribute("bufferSize") final String bufferSize,
077 @PluginAttribute("entityClassName") final String entityClassName,
078 @PluginAttribute("persistenceUnitName") final String persistenceUnitName) {
079 if (Strings.isEmpty(entityClassName) || Strings.isEmpty(persistenceUnitName)) {
080 LOGGER.error("Attributes entityClassName and persistenceUnitName are required for JPA Appender.");
081 return null;
082 }
083
084 final int bufferSizeInt = AbstractAppender.parseInt(bufferSize, 0);
085 final boolean ignoreExceptions = Booleans.parseBoolean(ignore, true);
086
087 try {
088 @SuppressWarnings("unchecked")
089 final Class<? extends AbstractLogEventWrapperEntity> entityClass =
090 (Class<? extends AbstractLogEventWrapperEntity>) Loader.loadClass(entityClassName);
091
092 if (!AbstractLogEventWrapperEntity.class.isAssignableFrom(entityClass)) {
093 LOGGER.error("Entity class [{}] does not extend AbstractLogEventWrapperEntity.", entityClassName);
094 return null;
095 }
096
097 try {
098 entityClass.getConstructor();
099 } catch (final NoSuchMethodException e) {
100 LOGGER.error("Entity class [{}] does not have a no-arg constructor. The JPA provider will reject it.",
101 entityClassName);
102 return null;
103 }
104
105 final Constructor<? extends AbstractLogEventWrapperEntity> entityConstructor =
106 entityClass.getConstructor(LogEvent.class);
107
108 final String managerName = "jpaManager{ description=" + name + ", bufferSize=" + bufferSizeInt
109 + ", persistenceUnitName=" + persistenceUnitName + ", entityClass=" + entityClass.getName() + '}';
110
111 final JpaDatabaseManager manager = JpaDatabaseManager.getJPADatabaseManager(
112 managerName, bufferSizeInt, entityClass, entityConstructor, persistenceUnitName
113 );
114 if (manager == null) {
115 return null;
116 }
117
118 return new JpaAppender(name, filter, ignoreExceptions, manager);
119 } catch (final ClassNotFoundException e) {
120 LOGGER.error("Could not load entity class [{}].", entityClassName, e);
121 return null;
122 } catch (final NoSuchMethodException e) {
123 LOGGER.error("Entity class [{}] does not have a constructor with a single argument of type LogEvent.",
124 entityClassName);
125 return null;
126 }
127 }
128 }