diff options
Diffstat (limited to 'src/org/apache/commons/lang3/exception/ExceptionUtils.java')
| -rw-r--r-- | src/org/apache/commons/lang3/exception/ExceptionUtils.java | 697 |
1 files changed, 0 insertions, 697 deletions
diff --git a/src/org/apache/commons/lang3/exception/ExceptionUtils.java b/src/org/apache/commons/lang3/exception/ExceptionUtils.java deleted file mode 100644 index de752a0..0000000 --- a/src/org/apache/commons/lang3/exception/ExceptionUtils.java +++ /dev/null @@ -1,697 +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.commons.lang3.exception; - -import java.io.PrintStream; -import java.io.PrintWriter; -import java.io.StringWriter; -import java.lang.reflect.InvocationTargetException; -import java.lang.reflect.Method; -import java.util.ArrayList; -import java.util.List; -import java.util.StringTokenizer; - -import org.apache.commons.lang3.ArrayUtils; -import org.apache.commons.lang3.ClassUtils; -import org.apache.commons.lang3.StringUtils; -import org.apache.commons.lang3.SystemUtils; - -/** - * <p>Provides utilities for manipulating and examining - * <code>Throwable</code> objects.</p> - * - * @since 1.0 - * @version $Id: ExceptionUtils.java 1144929 2011-07-10 18:26:16Z ggregory $ - */ -public class ExceptionUtils { - - /** - * <p>Used when printing stack frames to denote the start of a - * wrapped exception.</p> - * - * <p>Package private for accessibility by test suite.</p> - */ - static final String WRAPPED_MARKER = " [wrapped] "; - - /** - * <p>The names of methods commonly used to access a wrapped exception.</p> - */ - // TODO: Remove in Lang 4.0 - private static final String[] CAUSE_METHOD_NAMES = { - "getCause", - "getNextException", - "getTargetException", - "getException", - "getSourceException", - "getRootCause", - "getCausedByException", - "getNested", - "getLinkedException", - "getNestedException", - "getLinkedCause", - "getThrowable", - }; - - /** - * <p> - * Public constructor allows an instance of <code>ExceptionUtils</code> to be created, although that is not - * normally necessary. - * </p> - */ - public ExceptionUtils() { - super(); - } - - //----------------------------------------------------------------------- - /** - * <p>Returns the default names used when searching for the cause of an exception.</p> - * - * <p>This may be modified and used in the overloaded getCause(Throwable, String[]) method.</p> - * - * @return cloned array of the default method names - * @since 3.0 - * @deprecated This feature will be removed in Lang 4.0 - */ - @Deprecated - public static String[] getDefaultCauseMethodNames() { - return ArrayUtils.clone(CAUSE_METHOD_NAMES); - } - - //----------------------------------------------------------------------- - /** - * <p>Introspects the <code>Throwable</code> to obtain the cause.</p> - * - * <p>The method searches for methods with specific names that return a - * <code>Throwable</code> object. This will pick up most wrapping exceptions, - * including those from JDK 1.4. - * - * <p>The default list searched for are:</p> - * <ul> - * <li><code>getCause()</code></li> - * <li><code>getNextException()</code></li> - * <li><code>getTargetException()</code></li> - * <li><code>getException()</code></li> - * <li><code>getSourceException()</code></li> - * <li><code>getRootCause()</code></li> - * <li><code>getCausedByException()</code></li> - * <li><code>getNested()</code></li> - * </ul> - * - * <p>If none of the above is found, returns <code>null</code>.</p> - * - * @param throwable the throwable to introspect for a cause, may be null - * @return the cause of the <code>Throwable</code>, - * <code>null</code> if none found or null throwable input - * @since 1.0 - * @deprecated This feature will be removed in Lang 4.0 - */ - @Deprecated - public static Throwable getCause(Throwable throwable) { - return getCause(throwable, CAUSE_METHOD_NAMES); - } - - /** - * <p>Introspects the <code>Throwable</code> to obtain the cause.</p> - * - * <p>A <code>null</code> set of method names means use the default set. - * A <code>null</code> in the set of method names will be ignored.</p> - * - * @param throwable the throwable to introspect for a cause, may be null - * @param methodNames the method names, null treated as default set - * @return the cause of the <code>Throwable</code>, - * <code>null</code> if none found or null throwable input - * @since 1.0 - * @deprecated This feature will be removed in Lang 4.0 - */ - @Deprecated - public static Throwable getCause(Throwable throwable, String[] methodNames) { - if (throwable == null) { - return null; - } - - if (methodNames == null) { - methodNames = CAUSE_METHOD_NAMES; - } - - for (String methodName : methodNames) { - if (methodName != null) { - Throwable cause = getCauseUsingMethodName(throwable, methodName); - if (cause != null) { - return cause; - } - } - } - - return null; - } - - /** - * <p>Introspects the <code>Throwable</code> to obtain the root cause.</p> - * - * <p>This method walks through the exception chain to the last element, - * "root" of the tree, using {@link #getCause(Throwable)}, and - * returns that exception.</p> - * - * <p>From version 2.2, this method handles recursive cause structures - * that might otherwise cause infinite loops. If the throwable parameter - * has a cause of itself, then null will be returned. If the throwable - * parameter cause chain loops, the last element in the chain before the - * loop is returned.</p> - * - * @param throwable the throwable to get the root cause for, may be null - * @return the root cause of the <code>Throwable</code>, - * <code>null</code> if none found or null throwable input - */ - public static Throwable getRootCause(Throwable throwable) { - List<Throwable> list = getThrowableList(throwable); - return (list.size() < 2 ? null : (Throwable)list.get(list.size() - 1)); - } - - /** - * <p>Finds a <code>Throwable</code> by method name.</p> - * - * @param throwable the exception to examine - * @param methodName the name of the method to find and invoke - * @return the wrapped exception, or <code>null</code> if not found - */ - // TODO: Remove in Lang 4.0 - private static Throwable getCauseUsingMethodName(Throwable throwable, String methodName) { - Method method = null; - try { - method = throwable.getClass().getMethod(methodName); - } catch (NoSuchMethodException ignored) { // NOPMD - // exception ignored - } catch (SecurityException ignored) { // NOPMD - // exception ignored - } - - if (method != null && Throwable.class.isAssignableFrom(method.getReturnType())) { - try { - return (Throwable) method.invoke(throwable); - } catch (IllegalAccessException ignored) { // NOPMD - // exception ignored - } catch (IllegalArgumentException ignored) { // NOPMD - // exception ignored - } catch (InvocationTargetException ignored) { // NOPMD - // exception ignored - } - } - return null; - } - - //----------------------------------------------------------------------- - /** - * <p>Counts the number of <code>Throwable</code> objects in the - * exception chain.</p> - * - * <p>A throwable without cause will return <code>1</code>. - * A throwable with one cause will return <code>2</code> and so on. - * A <code>null</code> throwable will return <code>0</code>.</p> - * - * <p>From version 2.2, this method handles recursive cause structures - * that might otherwise cause infinite loops. The cause chain is - * processed until the end is reached, or until the next item in the - * chain is already in the result set.</p> - * - * @param throwable the throwable to inspect, may be null - * @return the count of throwables, zero if null input - */ - public static int getThrowableCount(Throwable throwable) { - return getThrowableList(throwable).size(); - } - - /** - * <p>Returns the list of <code>Throwable</code> objects in the - * exception chain.</p> - * - * <p>A throwable without cause will return an array containing - * one element - the input throwable. - * A throwable with one cause will return an array containing - * two elements. - the input throwable and the cause throwable. - * A <code>null</code> throwable will return an array of size zero.</p> - * - * <p>From version 2.2, this method handles recursive cause structures - * that might otherwise cause infinite loops. The cause chain is - * processed until the end is reached, or until the next item in the - * chain is already in the result set.</p> - * - * @see #getThrowableList(Throwable) - * @param throwable the throwable to inspect, may be null - * @return the array of throwables, never null - */ - public static Throwable[] getThrowables(Throwable throwable) { - List<Throwable> list = getThrowableList(throwable); - return list.toArray(new Throwable[list.size()]); - } - - /** - * <p>Returns the list of <code>Throwable</code> objects in the - * exception chain.</p> - * - * <p>A throwable without cause will return a list containing - * one element - the input throwable. - * A throwable with one cause will return a list containing - * two elements. - the input throwable and the cause throwable. - * A <code>null</code> throwable will return a list of size zero.</p> - * - * <p>This method handles recursive cause structures that might - * otherwise cause infinite loops. The cause chain is processed until - * the end is reached, or until the next item in the chain is already - * in the result set.</p> - * - * @param throwable the throwable to inspect, may be null - * @return the list of throwables, never null - * @since Commons Lang 2.2 - */ - public static List<Throwable> getThrowableList(Throwable throwable) { - List<Throwable> list = new ArrayList<Throwable>(); - while (throwable != null && list.contains(throwable) == false) { - list.add(throwable); - throwable = ExceptionUtils.getCause(throwable); - } - return list; - } - - //----------------------------------------------------------------------- - /** - * <p>Returns the (zero based) index of the first <code>Throwable</code> - * that matches the specified class (exactly) in the exception chain. - * Subclasses of the specified class do not match - see - * {@link #indexOfType(Throwable, Class)} for the opposite.</p> - * - * <p>A <code>null</code> throwable returns <code>-1</code>. - * A <code>null</code> type returns <code>-1</code>. - * No match in the chain returns <code>-1</code>.</p> - * - * @param throwable the throwable to inspect, may be null - * @param clazz the class to search for, subclasses do not match, null returns -1 - * @return the index into the throwable chain, -1 if no match or null input - */ - public static int indexOfThrowable(Throwable throwable, Class<?> clazz) { - return indexOf(throwable, clazz, 0, false); - } - - /** - * <p>Returns the (zero based) index of the first <code>Throwable</code> - * that matches the specified type in the exception chain from - * a specified index. - * Subclasses of the specified class do not match - see - * {@link #indexOfType(Throwable, Class, int)} for the opposite.</p> - * - * <p>A <code>null</code> throwable returns <code>-1</code>. - * A <code>null</code> type returns <code>-1</code>. - * No match in the chain returns <code>-1</code>. - * A negative start index is treated as zero. - * A start index greater than the number of throwables returns <code>-1</code>.</p> - * - * @param throwable the throwable to inspect, may be null - * @param clazz the class to search for, subclasses do not match, null returns -1 - * @param fromIndex the (zero based) index of the starting position, - * negative treated as zero, larger than chain size returns -1 - * @return the index into the throwable chain, -1 if no match or null input - */ - public static int indexOfThrowable(Throwable throwable, Class<?> clazz, int fromIndex) { - return indexOf(throwable, clazz, fromIndex, false); - } - - //----------------------------------------------------------------------- - /** - * <p>Returns the (zero based) index of the first <code>Throwable</code> - * that matches the specified class or subclass in the exception chain. - * Subclasses of the specified class do match - see - * {@link #indexOfThrowable(Throwable, Class)} for the opposite.</p> - * - * <p>A <code>null</code> throwable returns <code>-1</code>. - * A <code>null</code> type returns <code>-1</code>. - * No match in the chain returns <code>-1</code>.</p> - * - * @param throwable the throwable to inspect, may be null - * @param type the type to search for, subclasses match, null returns -1 - * @return the index into the throwable chain, -1 if no match or null input - * @since 2.1 - */ - public static int indexOfType(Throwable throwable, Class<?> type) { - return indexOf(throwable, type, 0, true); - } - - /** - * <p>Returns the (zero based) index of the first <code>Throwable</code> - * that matches the specified type in the exception chain from - * a specified index. - * Subclasses of the specified class do match - see - * {@link #indexOfThrowable(Throwable, Class)} for the opposite.</p> - * - * <p>A <code>null</code> throwable returns <code>-1</code>. - * A <code>null</code> type returns <code>-1</code>. - * No match in the chain returns <code>-1</code>. - * A negative start index is treated as zero. - * A start index greater than the number of throwables returns <code>-1</code>.</p> - * - * @param throwable the throwable to inspect, may be null - * @param type the type to search for, subclasses match, null returns -1 - * @param fromIndex the (zero based) index of the starting position, - * negative treated as zero, larger than chain size returns -1 - * @return the index into the throwable chain, -1 if no match or null input - * @since 2.1 - */ - public static int indexOfType(Throwable throwable, Class<?> type, int fromIndex) { - return indexOf(throwable, type, fromIndex, true); - } - - /** - * <p>Worker method for the <code>indexOfType</code> methods.</p> - * - * @param throwable the throwable to inspect, may be null - * @param type the type to search for, subclasses match, null returns -1 - * @param fromIndex the (zero based) index of the starting position, - * negative treated as zero, larger than chain size returns -1 - * @param subclass if <code>true</code>, compares with {@link Class#isAssignableFrom(Class)}, otherwise compares - * using references - * @return index of the <code>type</code> within throwables nested withing the specified <code>throwable</code> - */ - private static int indexOf(Throwable throwable, Class<?> type, int fromIndex, boolean subclass) { - if (throwable == null || type == null) { - return -1; - } - if (fromIndex < 0) { - fromIndex = 0; - } - Throwable[] throwables = ExceptionUtils.getThrowables(throwable); - if (fromIndex >= throwables.length) { - return -1; - } - if (subclass) { - for (int i = fromIndex; i < throwables.length; i++) { - if (type.isAssignableFrom(throwables[i].getClass())) { - return i; - } - } - } else { - for (int i = fromIndex; i < throwables.length; i++) { - if (type.equals(throwables[i].getClass())) { - return i; - } - } - } - return -1; - } - - //----------------------------------------------------------------------- - /** - * <p>Prints a compact stack trace for the root cause of a throwable - * to <code>System.err</code>.</p> - * - * <p>The compact stack trace starts with the root cause and prints - * stack frames up to the place where it was caught and wrapped. - * Then it prints the wrapped exception and continues with stack frames - * until the wrapper exception is caught and wrapped again, etc.</p> - * - * <p>The output of this method is consistent across JDK versions. - * Note that this is the opposite order to the JDK1.4 display.</p> - * - * <p>The method is equivalent to <code>printStackTrace</code> for throwables - * that don't have nested causes.</p> - * - * @param throwable the throwable to output - * @since 2.0 - */ - public static void printRootCauseStackTrace(Throwable throwable) { - printRootCauseStackTrace(throwable, System.err); - } - - /** - * <p>Prints a compact stack trace for the root cause of a throwable.</p> - * - * <p>The compact stack trace starts with the root cause and prints - * stack frames up to the place where it was caught and wrapped. - * Then it prints the wrapped exception and continues with stack frames - * until the wrapper exception is caught and wrapped again, etc.</p> - * - * <p>The output of this method is consistent across JDK versions. - * Note that this is the opposite order to the JDK1.4 display.</p> - * - * <p>The method is equivalent to <code>printStackTrace</code> for throwables - * that don't have nested causes.</p> - * - * @param throwable the throwable to output, may be null - * @param stream the stream to output to, may not be null - * @throws IllegalArgumentException if the stream is <code>null</code> - * @since 2.0 - */ - public static void printRootCauseStackTrace(Throwable throwable, PrintStream stream) { - if (throwable == null) { - return; - } - if (stream == null) { - throw new IllegalArgumentException("The PrintStream must not be null"); - } - String trace[] = getRootCauseStackTrace(throwable); - for (String element : trace) { - stream.println(element); - } - stream.flush(); - } - - /** - * <p>Prints a compact stack trace for the root cause of a throwable.</p> - * - * <p>The compact stack trace starts with the root cause and prints - * stack frames up to the place where it was caught and wrapped. - * Then it prints the wrapped exception and continues with stack frames - * until the wrapper exception is caught and wrapped again, etc.</p> - * - * <p>The output of this method is consistent across JDK versions. - * Note that this is the opposite order to the JDK1.4 display.</p> - * - * <p>The method is equivalent to <code>printStackTrace</code> for throwables - * that don't have nested causes.</p> - * - * @param throwable the throwable to output, may be null - * @param writer the writer to output to, may not be null - * @throws IllegalArgumentException if the writer is <code>null</code> - * @since 2.0 - */ - public static void printRootCauseStackTrace(Throwable throwable, PrintWriter writer) { - if (throwable == null) { - return; - } - if (writer == null) { - throw new IllegalArgumentException("The PrintWriter must not be null"); - } - String trace[] = getRootCauseStackTrace(throwable); - for (String element : trace) { - writer.println(element); - } - writer.flush(); - } - - //----------------------------------------------------------------------- - /** - * <p>Creates a compact stack trace for the root cause of the supplied - * <code>Throwable</code>.</p> - * - * <p>The output of this method is consistent across JDK versions. - * It consists of the root exception followed by each of its wrapping - * exceptions separated by '[wrapped]'. Note that this is the opposite - * order to the JDK1.4 display.</p> - * - * @param throwable the throwable to examine, may be null - * @return an array of stack trace frames, never null - * @since 2.0 - */ - public static String[] getRootCauseStackTrace(Throwable throwable) { - if (throwable == null) { - return ArrayUtils.EMPTY_STRING_ARRAY; - } - Throwable throwables[] = getThrowables(throwable); - int count = throwables.length; - List<String> frames = new ArrayList<String>(); - List<String> nextTrace = getStackFrameList(throwables[count - 1]); - for (int i = count; --i >= 0;) { - List<String> trace = nextTrace; - if (i != 0) { - nextTrace = getStackFrameList(throwables[i - 1]); - removeCommonFrames(trace, nextTrace); - } - if (i == count - 1) { - frames.add(throwables[i].toString()); - } else { - frames.add(WRAPPED_MARKER + throwables[i].toString()); - } - for (int j = 0; j < trace.size(); j++) { - frames.add(trace.get(j)); - } - } - return frames.toArray(new String[frames.size()]); - } - - /** - * <p>Removes common frames from the cause trace given the two stack traces.</p> - * - * @param causeFrames stack trace of a cause throwable - * @param wrapperFrames stack trace of a wrapper throwable - * @throws IllegalArgumentException if either argument is null - * @since 2.0 - */ - public static void removeCommonFrames(List<String> causeFrames, List<String> wrapperFrames) { - if (causeFrames == null || wrapperFrames == null) { - throw new IllegalArgumentException("The List must not be null"); - } - int causeFrameIndex = causeFrames.size() - 1; - int wrapperFrameIndex = wrapperFrames.size() - 1; - while (causeFrameIndex >= 0 && wrapperFrameIndex >= 0) { - // Remove the frame from the cause trace if it is the same - // as in the wrapper trace - String causeFrame = causeFrames.get(causeFrameIndex); - String wrapperFrame = wrapperFrames.get(wrapperFrameIndex); - if (causeFrame.equals(wrapperFrame)) { - causeFrames.remove(causeFrameIndex); - } - causeFrameIndex--; - wrapperFrameIndex--; - } - } - - //----------------------------------------------------------------------- - /** - * <p>Gets the stack trace from a Throwable as a String.</p> - * - * <p>The result of this method vary by JDK version as this method - * uses {@link Throwable#printStackTrace(java.io.PrintWriter)}. - * On JDK1.3 and earlier, the cause exception will not be shown - * unless the specified throwable alters printStackTrace.</p> - * - * @param throwable the <code>Throwable</code> to be examined - * @return the stack trace as generated by the exception's - * <code>printStackTrace(PrintWriter)</code> method - */ - public static String getStackTrace(Throwable throwable) { - StringWriter sw = new StringWriter(); - PrintWriter pw = new PrintWriter(sw, true); - throwable.printStackTrace(pw); - return sw.getBuffer().toString(); - } - - /** - * <p>Captures the stack trace associated with the specified - * <code>Throwable</code> object, decomposing it into a list of - * stack frames.</p> - * - * <p>The result of this method vary by JDK version as this method - * uses {@link Throwable#printStackTrace(java.io.PrintWriter)}. - * On JDK1.3 and earlier, the cause exception will not be shown - * unless the specified throwable alters printStackTrace.</p> - * - * @param throwable the <code>Throwable</code> to examine, may be null - * @return an array of strings describing each stack frame, never null - */ - public static String[] getStackFrames(Throwable throwable) { - if (throwable == null) { - return ArrayUtils.EMPTY_STRING_ARRAY; - } - return getStackFrames(getStackTrace(throwable)); - } - - //----------------------------------------------------------------------- - /** - * <p>Returns an array where each element is a line from the argument.</p> - * - * <p>The end of line is determined by the value of {@link SystemUtils#LINE_SEPARATOR}.</p> - * - * @param stackTrace a stack trace String - * @return an array where each element is a line from the argument - */ - static String[] getStackFrames(String stackTrace) { - String linebreak = SystemUtils.LINE_SEPARATOR; - StringTokenizer frames = new StringTokenizer(stackTrace, linebreak); - List<String> list = new ArrayList<String>(); - while (frames.hasMoreTokens()) { - list.add(frames.nextToken()); - } - return list.toArray(new String[list.size()]); - } - - /** - * <p>Produces a <code>List</code> of stack frames - the message - * is not included. Only the trace of the specified exception is - * returned, any caused by trace is stripped.</p> - * - * <p>This works in most cases - it will only fail if the exception - * message contains a line that starts with: - * <code>" at".</code></p> - * - * @param t is any throwable - * @return List of stack frames - */ - static List<String> getStackFrameList(Throwable t) { - String stackTrace = getStackTrace(t); - String linebreak = SystemUtils.LINE_SEPARATOR; - StringTokenizer frames = new StringTokenizer(stackTrace, linebreak); - List<String> list = new ArrayList<String>(); - boolean traceStarted = false; - while (frames.hasMoreTokens()) { - String token = frames.nextToken(); - // Determine if the line starts with <whitespace>at - int at = token.indexOf("at"); - if (at != -1 && token.substring(0, at).trim().length() == 0) { - traceStarted = true; - list.add(token); - } else if (traceStarted) { - break; - } - } - return list; - } - - //----------------------------------------------------------------------- - /** - * Gets a short message summarising the exception. - * <p> - * The message returned is of the form - * {ClassNameWithoutPackage}: {ThrowableMessage} - * - * @param th the throwable to get a message for, null returns empty string - * @return the message, non-null - * @since Commons Lang 2.2 - */ - public static String getMessage(Throwable th) { - if (th == null) { - return ""; - } - String clsName = ClassUtils.getShortClassName(th, null); - String msg = th.getMessage(); - return clsName + ": " + StringUtils.defaultString(msg); - } - - //----------------------------------------------------------------------- - /** - * Gets a short message summarising the root cause exception. - * <p> - * The message returned is of the form - * {ClassNameWithoutPackage}: {ThrowableMessage} - * - * @param th the throwable to get a message for, null returns empty string - * @return the message, non-null - * @since Commons Lang 2.2 - */ - public static String getRootCauseMessage(Throwable th) { - Throwable root = ExceptionUtils.getRootCause(th); - root = (root == null ? th : root); - return getMessage(root); - } - -} |