| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache license, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the license for the specific language governing permissions and |
| * limitations under the license. |
| */ |
| package org.apache.logging.log4j.core.impl; |
| |
| import java.lang.reflect.Constructor; |
| import java.util.Map; |
| import java.util.Map.Entry; |
| |
| import org.apache.logging.log4j.core.ContextDataInjector; |
| import org.apache.logging.log4j.core.LogEvent; |
| import org.apache.logging.log4j.core.util.Loader; |
| import org.apache.logging.log4j.util.IndexedStringMap; |
| import org.apache.logging.log4j.util.PropertiesUtil; |
| import org.apache.logging.log4j.util.ReadOnlyStringMap; |
| import org.apache.logging.log4j.util.SortedArrayStringMap; |
| import org.apache.logging.log4j.util.StringMap; |
| |
| /** |
| * Factory for creating the StringMap instances used to initialize LogEvents' {@linkplain LogEvent#getContextData() |
| * context data}. When context data is {@linkplain ContextDataInjector injected} into the log event, these StringMap |
| * instances may be either populated with key-value pairs from the context, or completely replaced altogether. |
| * <p> |
| * By default returns {@code SortedArrayStringMap} objects. Can be configured by setting system property |
| * {@code "log4j2.ContextData"} to the fully qualified class name of a class implementing the {@code StringMap} |
| * interface. The class must have a public default constructor, and if possible should also have a public constructor |
| * that takes a single {@code int} argument for the initial capacity. |
| * </p> |
| * |
| * @see LogEvent#getContextData() |
| * @see ContextDataInjector |
| * @see SortedArrayStringMap |
| * @since 2.7 |
| */ |
| public class ContextDataFactory { |
| private static final String CLASS_NAME = PropertiesUtil.getProperties().getStringProperty("log4j2.ContextData"); |
| private static final Class<? extends StringMap> CACHED_CLASS = createCachedClass(CLASS_NAME); |
| |
| /** |
| * In LOG4J2-2649 (https://issues.apache.org/jira/browse/LOG4J2-2649), |
| * the reporter said some reason about using graalvm to static compile. |
| * In graalvm doc (https://github.com/oracle/graal/blob/master/substratevm/LIMITATIONS.md), |
| * graalvm is not support MethodHandle now, so the Constructor need not to return MethodHandle. |
| */ |
| private static final Constructor<?> DEFAULT_CONSTRUCTOR = createDefaultConstructor(CACHED_CLASS); |
| private static final Constructor<?> INITIAL_CAPACITY_CONSTRUCTOR = createInitialCapacityConstructor(CACHED_CLASS); |
| |
| private static final StringMap EMPTY_STRING_MAP = createContextData(0); |
| |
| static { |
| EMPTY_STRING_MAP.freeze(); |
| } |
| |
| private static Class<? extends StringMap> createCachedClass(final String className) { |
| if (className == null) { |
| return null; |
| } |
| try { |
| return Loader.loadClass(className).asSubclass(IndexedStringMap.class); |
| } catch (final Exception any) { |
| return null; |
| } |
| } |
| |
| private static Constructor<?> createDefaultConstructor(final Class<? extends StringMap> cachedClass){ |
| if (cachedClass == null) { |
| return null; |
| } |
| try { |
| return cachedClass.getConstructor(); |
| } catch (final NoSuchMethodException | IllegalAccessError ignored) { |
| return null; |
| } |
| } |
| |
| private static Constructor<?> createInitialCapacityConstructor(final Class<? extends StringMap> cachedClass){ |
| if (cachedClass == null) { |
| return null; |
| } |
| try { |
| return cachedClass.getConstructor(int.class); |
| } catch (final NoSuchMethodException | IllegalAccessError ignored) { |
| return null; |
| } |
| } |
| |
| public static StringMap createContextData() { |
| if (DEFAULT_CONSTRUCTOR == null) { |
| return new SortedArrayStringMap(); |
| } |
| try { |
| return (IndexedStringMap) DEFAULT_CONSTRUCTOR.newInstance(); |
| } catch (final Throwable ignored) { |
| return new SortedArrayStringMap(); |
| } |
| } |
| |
| public static StringMap createContextData(final int initialCapacity) { |
| if (INITIAL_CAPACITY_CONSTRUCTOR == null) { |
| return new SortedArrayStringMap(initialCapacity); |
| } |
| try { |
| return (IndexedStringMap) INITIAL_CAPACITY_CONSTRUCTOR.newInstance(initialCapacity); |
| } catch (final Throwable ignored) { |
| return new SortedArrayStringMap(initialCapacity); |
| } |
| } |
| |
| public static StringMap createContextData(final Map<String, String> context) { |
| final StringMap contextData = createContextData(context.size()); |
| for (Entry<String, String> entry : context.entrySet()) { |
| contextData.putValue(entry.getKey(), entry.getValue()); |
| } |
| return contextData; |
| } |
| |
| public static StringMap createContextData(final ReadOnlyStringMap readOnlyStringMap) { |
| final StringMap contextData = createContextData(readOnlyStringMap.size()); |
| contextData.putAll(readOnlyStringMap); |
| return contextData; |
| } |
| |
| /** |
| * An empty pre-frozen IndexedStringMap. The returned object may be shared. |
| * |
| * @return an empty pre-frozen IndexedStringMap |
| */ |
| public static StringMap emptyFrozenContextData() { |
| return EMPTY_STRING_MAP; |
| } |
| |
| } |