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Posted to commits@logging.apache.org by ma...@apache.org on 2014/09/21 19:09:33 UTC
[4/8] git commit: Remove old caller class utility.
Remove old caller class utility.
Project: http://git-wip-us.apache.org/repos/asf/logging-log4j2/repo
Commit: http://git-wip-us.apache.org/repos/asf/logging-log4j2/commit/260b903b
Tree: http://git-wip-us.apache.org/repos/asf/logging-log4j2/tree/260b903b
Diff: http://git-wip-us.apache.org/repos/asf/logging-log4j2/diff/260b903b
Branch: refs/heads/master
Commit: 260b903b00e994c5bf5ee9d4ca6270a10dec2e1a
Parents: cbf0f72
Author: Matt Sicker <ma...@apache.org>
Authored: Fri Sep 5 16:54:23 2014 -0500
Committer: Matt Sicker <ma...@apache.org>
Committed: Fri Sep 5 16:54:23 2014 -0500
----------------------------------------------------------------------
.../core/impl/ReflectiveCallerClassUtility.java | 162 -------------------
.../impl/ReflectiveCallerClassUtilityTest.java | 43 -----
2 files changed, 205 deletions(-)
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http://git-wip-us.apache.org/repos/asf/logging-log4j2/blob/260b903b/log4j-core/src/main/java/org/apache/logging/log4j/core/impl/ReflectiveCallerClassUtility.java
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diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/impl/ReflectiveCallerClassUtility.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/impl/ReflectiveCallerClassUtility.java
deleted file mode 100644
index 93f2e6c..0000000
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/impl/ReflectiveCallerClassUtility.java
+++ /dev/null
@@ -1,162 +0,0 @@
-/*
- * 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.InvocationTargetException;
-import java.lang.reflect.Method;
-import java.lang.reflect.Modifier;
-
-import org.apache.logging.log4j.Logger;
-import org.apache.logging.log4j.core.util.Loader;
-import org.apache.logging.log4j.status.StatusLogger;
-
-/**
- * Utility class that handles the instability of the Sun/OpenJDK {@code sun.reflect.Reflection.getCallerClass(int)}
- * method.
- * <p>
- * <strong>Background:</strong> This method, available only in the Oracle/Sun/OpenJDK implementations of the Java
- * Virtual Machine, is a much more efficient mechanism for determining the {@link Class} of the caller of a particular
- * method. When it is not available, a {@link SecurityManager} is the second-best option. When this is also not
- * possible, the {@code StackTraceElement[]} returned by {@link Thread#getStackTrace()} must be used, and its
- * {@code String} class name converted to a {@code Class} using the slow {@link Class#forName}.
- * </p>
- * <p>
- * As of Java 8, the {@code getCallerClass(int)} method has been removed from Oracle/OpenJDK and is no longer usable. A
- * back-port of the feature that resulted in this change was made in Java 7u25, but the {@code getCallerClass(int)} was
- * left around for that version and deprecated, with the intention of being removed in 7u40. By coincidence, the change
- * actually broke {@code getCallerClass(int)} (the return value was inadvertently offset by 1 stack frame). This was
- * actually a good thing, because it made the hundreds of libraries and frameworks relying on this method aware of what
- * the JDK developers were up to.
- * </p>
- * <p>
- * After much community backlash, the JDK team agreed to restore {@code getCallerClass(int)} and keep its existing
- * behavior for the rest of Java 7. However, the method is deprecated in Java 8, supposedly won't be in Java 9 (unless
- * no public API is exposed which may force them to keep it), and so backup options must be used. This class:
- * </p>
- * <ul>
- * <li>Uses {@code getCallerClass(int)} the traditional way when possible.</li>
- * <li>Uses {@code getCallerClass(int)} with an adjusted offset in Oracle/OpenJDK 7u25.</li>
- * <li>Returns null otherwise. (Currently, it is the caller's responsibility to use the backup mechanisms.)</li>
- * </ul>
- * <p>
- * <strong>IMPORTANT NOTE:</strong> This class should not be relied upon. It is considered an internal class and could
- * change at any time, breaking your code if you use it. Specifically, as a possible public API replacement for
- * {@code getCallerClass(int)} develops in Java 9, this class is very likely to change or even go away.
- * </p>
- */
-public final class ReflectiveCallerClassUtility {
-
- private static final Logger LOGGER = StatusLogger.getLogger();
-
- private static final boolean GET_CALLER_CLASS_SUPPORTED;
-
- private static final Method GET_CALLER_CLASS_METHOD;
-
- static final int JAVA_7U25_COMPENSATION_OFFSET;
-
- static {
- Method getCallerClass = null;
- int java7u25CompensationOffset = 0;
-
- try {
- final ClassLoader loader = Loader.getClassLoader();
- // Use wildcard to avoid compile-time reference.
- final Class<?> clazz = loader.loadClass("sun.reflect.Reflection");
- final Method[] methods = clazz.getMethods();
- for (final Method method : methods) {
- final int modifier = method.getModifiers();
- final Class<?>[] parameterTypes = method.getParameterTypes();
- if (method.getName().equals("getCallerClass") && Modifier.isStatic(modifier) &&
- parameterTypes.length == 1 && parameterTypes[0] == int.class) {
- getCallerClass = method;
- break;
- }
- }
-
- if (getCallerClass == null) {
- LOGGER.info("sun.reflect.Reflection#getCallerClass does not exist.");
- } else {
- Object o = getCallerClass.invoke(null, 0);
- if (o == null || o != clazz) {
- getCallerClass = null;
- LOGGER.warn("sun.reflect.Reflection#getCallerClass returned unexpected value of [{}] and is " +
- "unusable. Will fall back to another option.", o);
- } else {
- o = getCallerClass.invoke(null, 1);
- if (o == clazz) {
- java7u25CompensationOffset = 1;
- LOGGER.warn("sun.reflect.Reflection#getCallerClass is broken in Java 7u25. " +
- "You should upgrade to 7u40. Using alternate stack offset to compensate.");
- }
- }
- }
- } catch (final ClassNotFoundException e) {
- LOGGER.info("sun.reflect.Reflection is not installed.");
- } catch (final IllegalAccessException e) {
- LOGGER.info("sun.reflect.Reflection#getCallerClass is not accessible.");
- } catch (final InvocationTargetException e) {
- LOGGER.info("sun.reflect.Reflection#getCallerClass is not supported.");
- }
-
- if (getCallerClass == null) {
- GET_CALLER_CLASS_SUPPORTED = false;
- GET_CALLER_CLASS_METHOD = null;
- JAVA_7U25_COMPENSATION_OFFSET = -1;
- } else {
- GET_CALLER_CLASS_SUPPORTED = true;
- GET_CALLER_CLASS_METHOD = getCallerClass;
- JAVA_7U25_COMPENSATION_OFFSET = java7u25CompensationOffset;
- }
- }
-
- private ReflectiveCallerClassUtility() {
-
- }
-
- /**
- * Indicates whether {@code getCallerClass(int)} can be used on this JVM.
- *
- * @return {@code true} if it can be used. If {@code false}, {@link #getCaller} should not be called. Use a backup
- * mechanism instead.
- */
- public static boolean isSupported() {
- return GET_CALLER_CLASS_SUPPORTED;
- }
-
- /**
- * Reflectively calls {@code getCallerClass(int)}, compensating for the additional frame on the stack, and
- * compensating for the Java 7u25 bug if necessary. You should check with {@link #isSupported} before using this
- * method.
- *
- * @param depth The depth of the caller to retrieve.
- * @return the caller class, or {@code null} if {@code getCallerClass(int)} is not supported.
- */
- public static Class<?> getCaller(final int depth) {
- if (!GET_CALLER_CLASS_SUPPORTED) {
- return null;
- }
-
- try {
- return (Class<?>) GET_CALLER_CLASS_METHOD.invoke(null, depth + 1 + JAVA_7U25_COMPENSATION_OFFSET);
- } catch (final IllegalAccessException ignore) {
- LOGGER.warn("Should not have failed to call getCallerClass.");
- } catch (final InvocationTargetException ignore) {
- LOGGER.warn("Should not have failed to call getCallerClass.");
- }
- return null;
- }
-}
http://git-wip-us.apache.org/repos/asf/logging-log4j2/blob/260b903b/log4j-core/src/test/java/org/apache/logging/log4j/core/impl/ReflectiveCallerClassUtilityTest.java
----------------------------------------------------------------------
diff --git a/log4j-core/src/test/java/org/apache/logging/log4j/core/impl/ReflectiveCallerClassUtilityTest.java b/log4j-core/src/test/java/org/apache/logging/log4j/core/impl/ReflectiveCallerClassUtilityTest.java
deleted file mode 100644
index 6761163..0000000
--- a/log4j-core/src/test/java/org/apache/logging/log4j/core/impl/ReflectiveCallerClassUtilityTest.java
+++ /dev/null
@@ -1,43 +0,0 @@
-/*
- * 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 org.junit.Before;
-import org.junit.Test;
-import sun.reflect.Reflection;
-
-import static org.junit.Assert.assertSame;
-import static org.junit.Assume.assumeTrue;
-
-public class ReflectiveCallerClassUtilityTest {
-
- @Before
- public void setUp() throws Exception {
- assumeTrue(ReflectiveCallerClassUtility.isSupported());
- }
-
- @Test
- public void testGetCaller() throws Exception {
- for (int i = 1; i <= 6; i++) {
- assertSame(String.format("%d is not the same", i),
- Reflection.getCallerClass(i + ReflectiveCallerClassUtility.JAVA_7U25_COMPENSATION_OFFSET),
- ReflectiveCallerClassUtility.getCaller(i)
- );
- }
- }
-}