| /* |
| * 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.util.HashMap; |
| import java.util.List; |
| import java.util.Map; |
| |
| import org.apache.logging.log4j.ThreadContext; |
| import org.apache.logging.log4j.core.ContextDataInjector; |
| import org.apache.logging.log4j.core.config.Property; |
| import org.apache.logging.log4j.spi.ReadOnlyThreadContextMap; |
| import org.apache.logging.log4j.util.ReadOnlyStringMap; |
| import org.apache.logging.log4j.util.StringMap; |
| |
| /** |
| * {@code ThreadContextDataInjector} contains a number of strategies for copying key-value pairs from the various |
| * {@code ThreadContext} map implementations into a {@code StringMap}. In the case of duplicate keys, |
| * thread context values overwrite configuration {@code Property} values. |
| * <p> |
| * These are the default {@code ContextDataInjector} objects returned by the {@link ContextDataInjectorFactory}. |
| * </p> |
| * |
| * @see org.apache.logging.log4j.ThreadContext |
| * @see Property |
| * @see ReadOnlyStringMap |
| * @see ContextDataInjector |
| * @see ContextDataInjectorFactory |
| * @since 2.7 |
| */ |
| public class ThreadContextDataInjector { |
| |
| /** |
| * Default {@code ContextDataInjector} for the legacy {@code Map<String, String>}-based ThreadContext (which is |
| * also the ThreadContext implementation used for web applications). |
| * <p> |
| * This injector always puts key-value pairs into the specified reusable StringMap. |
| */ |
| public static class ForDefaultThreadContextMap implements ContextDataInjector { |
| |
| /** |
| * Puts key-value pairs from both the specified list of properties as well as the thread context into the |
| * specified reusable StringMap. |
| * |
| * @param props list of configuration properties, may be {@code null} |
| * @param ignore a {@code StringMap} instance from the log event |
| * @return a {@code StringMap} combining configuration properties with thread context data |
| */ |
| @Override |
| public StringMap injectContextData(final List<Property> props, final StringMap ignore) { |
| |
| final Map<String, String> copy = ThreadContext.getImmutableContext(); |
| |
| // The DefaultThreadContextMap stores context data in a Map<String, String>. |
| // This is a copy-on-write data structure so we are sure ThreadContext changes will not affect our copy. |
| // If there are no configuration properties returning a thin wrapper around the copy |
| // is faster than copying the elements into the LogEvent's reusable StringMap. |
| if (props == null || props.isEmpty()) { |
| // this will replace the LogEvent's context data with the returned instance. |
| // NOTE: must mark as frozen or downstream components may attempt to modify (UnsupportedOperationEx) |
| return copy.isEmpty() ? ContextDataFactory.emptyFrozenContextData() : frozenStringMap(copy); |
| } |
| // If the list of Properties is non-empty we need to combine the properties and the ThreadContext |
| // data. Note that we cannot reuse the specified StringMap: some Loggers may have properties defined |
| // and others not, so the LogEvent's context data may have been replaced with an immutable copy from |
| // the ThreadContext - this will throw an UnsupportedOperationException if we try to modify it. |
| final StringMap result = new JdkMapAdapterStringMap(new HashMap<>(copy)); |
| for (int i = 0; i < props.size(); i++) { |
| final Property prop = props.get(i); |
| if (!copy.containsKey(prop.getName())) { |
| result.putValue(prop.getName(), prop.getValue()); |
| } |
| } |
| result.freeze(); |
| return result; |
| } |
| |
| private static JdkMapAdapterStringMap frozenStringMap(final Map<String, String> copy) { |
| final JdkMapAdapterStringMap result = new JdkMapAdapterStringMap(copy); |
| result.freeze(); |
| return result; |
| } |
| |
| @Override |
| public ReadOnlyStringMap rawContextData() { |
| final ReadOnlyThreadContextMap map = ThreadContext.getThreadContextMap(); |
| if (map instanceof ReadOnlyStringMap) { |
| return (ReadOnlyStringMap) map; |
| } |
| // note: default ThreadContextMap is null |
| final Map<String, String> copy = ThreadContext.getImmutableContext(); |
| return copy.isEmpty() ? ContextDataFactory.emptyFrozenContextData() : new JdkMapAdapterStringMap(copy); |
| } |
| } |
| |
| /** |
| * The {@code ContextDataInjector} used when the ThreadContextMap implementation is a garbage-free |
| * StringMap-based data structure. |
| * <p> |
| * This injector always puts key-value pairs into the specified reusable StringMap. |
| */ |
| public static class ForGarbageFreeThreadContextMap implements ContextDataInjector { |
| /** |
| * Puts key-value pairs from both the specified list of properties as well as the thread context into the |
| * specified reusable StringMap. |
| * |
| * @param props list of configuration properties, may be {@code null} |
| * @param reusable a {@code StringMap} instance that may be reused to avoid creating temporary objects |
| * @return a {@code StringMap} combining configuration properties with thread context data |
| */ |
| @Override |
| public StringMap injectContextData(final List<Property> props, final StringMap reusable) { |
| // When the ThreadContext is garbage-free, we must copy its key-value pairs into the specified reusable |
| // StringMap. We cannot return the ThreadContext's internal data structure because it may be modified later |
| // and such modifications should not be reflected in the log event. |
| copyProperties(props, reusable); |
| |
| final ReadOnlyStringMap immutableCopy = ThreadContext.getThreadContextMap().getReadOnlyContextData(); |
| reusable.putAll(immutableCopy); |
| return reusable; |
| } |
| |
| @Override |
| public ReadOnlyStringMap rawContextData() { |
| return ThreadContext.getThreadContextMap().getReadOnlyContextData(); |
| } |
| } |
| |
| /** |
| * The {@code ContextDataInjector} used when the ThreadContextMap implementation is a copy-on-write |
| * StringMap-based data structure. |
| * <p> |
| * If there are no configuration properties, this injector will return the thread context's internal data |
| * structure. Otherwise the configuration properties are combined with the thread context key-value pairs into the |
| * specified reusable StringMap. |
| */ |
| public static class ForCopyOnWriteThreadContextMap implements ContextDataInjector { |
| /** |
| * If there are no configuration properties, this injector will return the thread context's internal data |
| * structure. Otherwise the configuration properties are combined with the thread context key-value pairs into the |
| * specified reusable StringMap. |
| * |
| * @param props list of configuration properties, may be {@code null} |
| * @param ignore a {@code StringMap} instance from the log event |
| * @return a {@code StringMap} combining configuration properties with thread context data |
| */ |
| @Override |
| public StringMap injectContextData(final List<Property> props, final StringMap ignore) { |
| // If there are no configuration properties we want to just return the ThreadContext's StringMap: |
| // it is a copy-on-write data structure so we are sure ThreadContext changes will not affect our copy. |
| final StringMap immutableCopy = ThreadContext.getThreadContextMap().getReadOnlyContextData(); |
| if (props == null || props.isEmpty()) { |
| return immutableCopy; // this will replace the LogEvent's context data with the returned instance |
| } |
| // However, if the list of Properties is non-empty we need to combine the properties and the ThreadContext |
| // data. Note that we cannot reuse the specified StringMap: some Loggers may have properties defined |
| // and others not, so the LogEvent's context data may have been replaced with an immutable copy from |
| // the ThreadContext - this will throw an UnsupportedOperationException if we try to modify it. |
| final StringMap result = ContextDataFactory.createContextData(props.size() + immutableCopy.size()); |
| copyProperties(props, result); |
| result.putAll(immutableCopy); |
| return result; |
| } |
| |
| @Override |
| public ReadOnlyStringMap rawContextData() { |
| return ThreadContext.getThreadContextMap().getReadOnlyContextData(); |
| } |
| } |
| |
| /** |
| * Copies key-value pairs from the specified property list into the specified {@code StringMap}. |
| * |
| * @param properties list of configuration properties, may be {@code null} |
| * @param result the {@code StringMap} object to add the key-values to. Must be non-{@code null}. |
| */ |
| public static void copyProperties(final List<Property> properties, final StringMap result) { |
| if (properties != null) { |
| for (int i = 0; i < properties.size(); i++) { |
| final Property prop = properties.get(i); |
| result.putValue(prop.getName(), prop.getValue()); |
| } |
| } |
| } |
| } |