X-Git-Url: http://source.jalview.org/gitweb/?a=blobdiff_plain;f=unused%2Fsrcjar_unused%2Forg%2Fapache%2Flog4j%2FMDC.java;fp=unused%2Fsrcjar_unused%2Forg%2Fapache%2Flog4j%2FMDC.java;h=c07efed0f078081e9352fc377483295e5b4e6759;hb=7e01e1b3e9c8abdf952e085dba51e9266f12b1ee;hp=0000000000000000000000000000000000000000;hpb=88635c3965bb2f1f45e53c2d5f66fed19b93012a;p=jalview.git diff --git a/unused/srcjar_unused/org/apache/log4j/MDC.java b/unused/srcjar_unused/org/apache/log4j/MDC.java new file mode 100644 index 0000000..c07efed --- /dev/null +++ b/unused/srcjar_unused/org/apache/log4j/MDC.java @@ -0,0 +1,212 @@ +/* + * 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.log4j; + +import org.apache.log4j.helpers.Loader; +import org.apache.log4j.helpers.ThreadLocalMap; + +import java.lang.reflect.InvocationTargetException; +import java.lang.reflect.Method; +import java.util.Hashtable; + +/** + * The MDC class is similar to the {@link NDC} class except that it is + * based on a map instead of a stack. It provides mapped + * diagnostic contexts. A Mapped Diagnostic Context, or + * MDC in short, is an instrument for distinguishing interleaved log + * output from different sources. Log output is typically interleaved + * when a server handles multiple clients near-simultaneously. + *
+ *The MDC is managed on a per thread basis. A + * child thread automatically inherits a copy of the mapped + * diagnostic context of its parent. + *
+ *The MDC class requires JDK 1.2 or above. Under JDK 1.1 the MDC + * will always return empty values but otherwise will not affect or + * harm your application.
+ * + *Attention: the application is required to clean up. In web applications + * this can happen with creating a Servlet Filter and overriding the + * onFilter method like:
+ * + *+ * try { + * MDC.put(myKey); + * chain.doFilter(request, response); + * } finally { + * MDC.remove(myKey); + * } + *+ * + *
Please also see: {@link http://logging.apache.org/log4j/1.2/faq.html#mdcmemoryleak}
+ * + * @author Ceki Gülcü + * @since 1.2 + */ +public class MDC { + + final static MDC mdc = new MDC(); + + static final int HT_SIZE = 7; + + boolean java1; + + Object tlm; + + private Method removeMethod; + + private MDC() { + java1 = Loader.isJava1(); + if (!java1) { + tlm = new ThreadLocalMap(); + } + + try { + removeMethod = ThreadLocal.class.getMethod("remove", null); + } catch (NoSuchMethodException e) { + // don't do anything - java prior 1.5 + } + } + + /** + * Put a context value (theo
parameter) as identified
+ * with the key
parameter into the current thread's
+ * context map.
+ *
+ * If the current thread does not have a context map it is
+ * created as a side effect.
+ */
+ public static void put(String key, Object o) {
+ if (mdc != null) {
+ mdc.put0(key, o);
+ }
+ }
+
+ /**
+ * Get the context identified by the key
parameter.
+ *
This method has no side effects.
+ */
+ public static Object get(String key) {
+ if (mdc != null) {
+ return mdc.get0(key);
+ }
+ return null;
+ }
+
+ /**
+ * Remove the the context identified by the key
+ * parameter.
+ */
+ public static void remove(String key) {
+ if (mdc != null) {
+ mdc.remove0(key);
+ }
+ }
+
+
+ /**
+ * Get the current thread's MDC as a hashtable. This method is
+ * intended to be used internally.
+ */
+ public static Hashtable getContext() {
+ if (mdc != null) {
+ return mdc.getContext0();
+ } else {
+ return null;
+ }
+ }
+
+ /**
+ * Remove all values from the MDC.
+ *
+ * @since 1.2.16
+ */
+ public static void clear() {
+ if (mdc != null) {
+ mdc.clear0();
+ }
+ }
+
+
+ private void put0(String key, Object o) {
+ if (java1 || tlm == null) {
+ return;
+ } else {
+ Hashtable ht = (Hashtable) ((ThreadLocalMap) tlm).get();
+ if (ht == null) {
+ ht = new Hashtable(HT_SIZE);
+ ((ThreadLocalMap) tlm).set(ht);
+ }
+ ht.put(key, o);
+ }
+ }
+
+ private Object get0(String key) {
+ if (java1 || tlm == null) {
+ return null;
+ } else {
+ Hashtable ht = (Hashtable) ((ThreadLocalMap) tlm).get();
+ if (ht != null && key != null) {
+ return ht.get(key);
+ } else {
+ return null;
+ }
+ }
+ }
+
+ private void remove0(String key) {
+ if (!java1 && tlm != null) {
+ Hashtable ht = (Hashtable) ((ThreadLocalMap) tlm).get();
+ if (ht != null) {
+ ht.remove(key);
+ // clean up if this was the last key
+ if (ht.isEmpty()) {
+ clear0();
+ }
+ }
+ }
+ }
+
+ private Hashtable getContext0() {
+ if (java1 || tlm == null) {
+ return null;
+ } else {
+ return (Hashtable) ((ThreadLocalMap) tlm).get();
+ }
+ }
+
+ private void clear0() {
+ if (!java1 && tlm != null) {
+ Hashtable ht = (Hashtable) ((ThreadLocalMap) tlm).get();
+ if (ht != null) {
+ ht.clear();
+ }
+ if (removeMethod != null) {
+ // java 1.3/1.4 does not have remove - will suffer from a memory leak
+ try {
+ removeMethod.invoke(tlm, null);
+ } catch (IllegalAccessException e) {
+ // should not happen
+ } catch (InvocationTargetException e) {
+ // should not happen
+ }
+ }
+ }
+ }
+}