| /* |
| * 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.lang.exception; |
| |
| import java.io.PrintStream; |
| import java.io.PrintWriter; |
| import java.io.StringWriter; |
| import java.lang.reflect.Field; |
| import java.lang.reflect.InvocationTargetException; |
| import java.lang.reflect.Method; |
| import java.sql.SQLException; |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.List; |
| import java.util.StringTokenizer; |
| |
| import org.apache.commons.lang.ArrayUtils; |
| import org.apache.commons.lang.ClassUtils; |
| import org.apache.commons.lang.NullArgumentException; |
| import org.apache.commons.lang.StringUtils; |
| import org.apache.commons.lang.SystemUtils; |
| |
| /** |
| * <p>Provides utilities for manipulating and examining |
| * <code>Throwable</code> objects.</p> |
| * |
| * @author Apache Software Foundation |
| * @author Daniel L. Rall |
| * @author Dmitri Plotnikov |
| * @author <a href="mailto:ggregory@seagullsw.com">Gary Gregory</a> |
| * @author Pete Gieser |
| * @since 1.0 |
| * @version $Id$ |
| */ |
| 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] "; |
| |
| // Lock object for CAUSE_METHOD_NAMES |
| private static final Object CAUSE_METHOD_NAMES_LOCK = new Object(); |
| |
| /** |
| * <p>The names of methods commonly used to access a wrapped exception.</p> |
| */ |
| private static String[] CAUSE_METHOD_NAMES = { |
| "getCause", |
| "getNextException", |
| "getTargetException", |
| "getException", |
| "getSourceException", |
| "getRootCause", |
| "getCausedByException", |
| "getNested", |
| "getLinkedException", |
| "getNestedException", |
| "getLinkedCause", |
| "getThrowable", |
| }; |
| |
| /** |
| * <p>The Method object for Java 1.4 getCause.</p> |
| */ |
| private static final Method THROWABLE_CAUSE_METHOD; |
| |
| /** |
| * <p>The Method object for Java 1.4 initCause.</p> |
| */ |
| private static final Method THROWABLE_INITCAUSE_METHOD; |
| |
| static { |
| Method causeMethod; |
| try { |
| causeMethod = Throwable.class.getMethod("getCause", null); |
| } catch (Exception e) { |
| causeMethod = null; |
| } |
| THROWABLE_CAUSE_METHOD = causeMethod; |
| try { |
| causeMethod = Throwable.class.getMethod("initCause", new Class[]{Throwable.class}); |
| } catch (Exception e) { |
| causeMethod = null; |
| } |
| THROWABLE_INITCAUSE_METHOD = causeMethod; |
| } |
| |
| /** |
| * <p> |
| * Public constructor allows an instance of <code>ExceptionUtils</code> to be created, although that is not |
| * normally necessary. |
| * </p> |
| */ |
| public ExceptionUtils() { |
| super(); |
| } |
| |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Adds to the list of method names used in the search for <code>Throwable</code> |
| * objects.</p> |
| * |
| * @param methodName the methodName to add to the list, <code>null</code> |
| * and empty strings are ignored |
| * @since 2.0 |
| */ |
| public static void addCauseMethodName(String methodName) { |
| if (StringUtils.isNotEmpty(methodName) && !isCauseMethodName(methodName)) { |
| List list = getCauseMethodNameList(); |
| if (list.add(methodName)) { |
| synchronized(CAUSE_METHOD_NAMES_LOCK) { |
| CAUSE_METHOD_NAMES = toArray(list); |
| } |
| } |
| } |
| } |
| |
| /** |
| * <p>Removes from the list of method names used in the search for <code>Throwable</code> |
| * objects.</p> |
| * |
| * @param methodName the methodName to remove from the list, <code>null</code> |
| * and empty strings are ignored |
| * @since 2.1 |
| */ |
| public static void removeCauseMethodName(String methodName) { |
| if (StringUtils.isNotEmpty(methodName)) { |
| List list = getCauseMethodNameList(); |
| if (list.remove(methodName)) { |
| synchronized(CAUSE_METHOD_NAMES_LOCK) { |
| CAUSE_METHOD_NAMES = toArray(list); |
| } |
| } |
| } |
| } |
| |
| /** |
| * <p>Sets the cause of a <code>Throwable</code> using introspection, allowing |
| * source code compatibility between pre-1.4 and post-1.4 Java releases.</p> |
| * |
| * <p>The typical use of this method is inside a constructor as in |
| * the following example:</p> |
| * |
| * <pre> |
| * import org.apache.commons.lang.exception.ExceptionUtils; |
| * |
| * public class MyException extends Exception { |
| * |
| * public MyException(String msg) { |
| * super(msg); |
| * } |
| * |
| * public MyException(String msg, Throwable cause) { |
| * super(msg); |
| * ExceptionUtils.setCause(this, cause); |
| * } |
| * } |
| * </pre> |
| * |
| * @param target the target <code>Throwable</code> |
| * @param cause the <code>Throwable</code> to set in the target |
| * @return a <code>true</code> if the target has been modified |
| * @since 2.2 |
| */ |
| public static boolean setCause(Throwable target, Throwable cause) { |
| if (target == null) { |
| throw new NullArgumentException("target"); |
| } |
| Object[] causeArgs = new Object[]{cause}; |
| boolean modifiedTarget = false; |
| if (THROWABLE_INITCAUSE_METHOD != null) { |
| try { |
| THROWABLE_INITCAUSE_METHOD.invoke(target, causeArgs); |
| modifiedTarget = true; |
| } catch (IllegalAccessException ignored) { |
| // Exception ignored. |
| } catch (InvocationTargetException ignored) { |
| // Exception ignored. |
| } |
| } |
| try { |
| Method setCauseMethod = target.getClass().getMethod("setCause", new Class[]{Throwable.class}); |
| setCauseMethod.invoke(target, causeArgs); |
| modifiedTarget = true; |
| } catch (NoSuchMethodException ignored) { |
| // Exception ignored. |
| } catch (IllegalAccessException ignored) { |
| // Exception ignored. |
| } catch (InvocationTargetException ignored) { |
| // Exception ignored. |
| } |
| return modifiedTarget; |
| } |
| |
| /** |
| * Returns the given list as a <code>String[]</code>. |
| * @param list a list to transform. |
| * @return the given list as a <code>String[]</code>. |
| */ |
| private static String[] toArray(List list) { |
| return (String[]) list.toArray(new String[list.size()]); |
| } |
| |
| /** |
| * Returns {@link #CAUSE_METHOD_NAMES} as a List. |
| * |
| * @return {@link #CAUSE_METHOD_NAMES} as a List. |
| */ |
| private static ArrayList getCauseMethodNameList() { |
| synchronized(CAUSE_METHOD_NAMES_LOCK) { |
| return new ArrayList(Arrays.asList(CAUSE_METHOD_NAMES)); |
| } |
| } |
| |
| /** |
| * <p>Tests if the list of method names used in the search for <code>Throwable</code> |
| * objects include the given name.</p> |
| * |
| * @param methodName the methodName to search in the list. |
| * @return if the list of method names used in the search for <code>Throwable</code> |
| * objects include the given name. |
| * @since 2.1 |
| */ |
| public static boolean isCauseMethodName(String methodName) { |
| synchronized(CAUSE_METHOD_NAMES_LOCK) { |
| return ArrayUtils.indexOf(CAUSE_METHOD_NAMES, methodName) >= 0; |
| } |
| } |
| |
| //----------------------------------------------------------------------- |
| /** |
| * <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, and |
| * {@link org.apache.commons.lang.exception.NestableException NestableException}. |
| * The method names can be added to using {@link #addCauseMethodName(String)}.</p> |
| * |
| * <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>In the absence of any such method, the object is inspected for a |
| * <code>detail</code> field assignable to a <code>Throwable</code>.</p> |
| * |
| * <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 |
| */ |
| public static Throwable getCause(Throwable throwable) { |
| synchronized(CAUSE_METHOD_NAMES_LOCK) { |
| return getCause(throwable, CAUSE_METHOD_NAMES); |
| } |
| } |
| |
| /** |
| * <p>Introspects the <code>Throwable</code> to obtain the cause.</p> |
| * |
| * <ol> |
| * <li>Try known exception types.</li> |
| * <li>Try the supplied array of method names.</li> |
| * <li>Try the field 'detail'.</li> |
| * </ol> |
| * |
| * <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 |
| */ |
| public static Throwable getCause(Throwable throwable, String[] methodNames) { |
| if (throwable == null) { |
| return null; |
| } |
| Throwable cause = getCauseUsingWellKnownTypes(throwable); |
| if (cause == null) { |
| if (methodNames == null) { |
| synchronized(CAUSE_METHOD_NAMES_LOCK) { |
| methodNames = CAUSE_METHOD_NAMES; |
| } |
| } |
| for (int i = 0; i < methodNames.length; i++) { |
| String methodName = methodNames[i]; |
| if (methodName != null) { |
| cause = getCauseUsingMethodName(throwable, methodName); |
| if (cause != null) { |
| break; |
| } |
| } |
| } |
| |
| if (cause == null) { |
| cause = getCauseUsingFieldName(throwable, "detail"); |
| } |
| } |
| return cause; |
| } |
| |
| /** |
| * <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 list = getThrowableList(throwable); |
| return (list.size() < 2 ? null : (Throwable)list.get(list.size() - 1)); |
| } |
| |
| /** |
| * <p>Finds a <code>Throwable</code> for known types.</p> |
| * |
| * <p>Uses <code>instanceof</code> checks to examine the exception, |
| * looking for well known types which could contain chained or |
| * wrapped exceptions.</p> |
| * |
| * @param throwable the exception to examine |
| * @return the wrapped exception, or <code>null</code> if not found |
| */ |
| private static Throwable getCauseUsingWellKnownTypes(Throwable throwable) { |
| if (throwable instanceof Nestable) { |
| return ((Nestable) throwable).getCause(); |
| } else if (throwable instanceof SQLException) { |
| return ((SQLException) throwable).getNextException(); |
| } else if (throwable instanceof InvocationTargetException) { |
| return ((InvocationTargetException) throwable).getTargetException(); |
| } else { |
| return null; |
| } |
| } |
| |
| /** |
| * <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 |
| */ |
| private static Throwable getCauseUsingMethodName(Throwable throwable, String methodName) { |
| Method method = null; |
| try { |
| method = throwable.getClass().getMethod(methodName, null); |
| } catch (NoSuchMethodException ignored) { |
| // exception ignored |
| } catch (SecurityException ignored) { |
| // exception ignored |
| } |
| |
| if (method != null && Throwable.class.isAssignableFrom(method.getReturnType())) { |
| try { |
| return (Throwable) method.invoke(throwable, ArrayUtils.EMPTY_OBJECT_ARRAY); |
| } catch (IllegalAccessException ignored) { |
| // exception ignored |
| } catch (IllegalArgumentException ignored) { |
| // exception ignored |
| } catch (InvocationTargetException ignored) { |
| // exception ignored |
| } |
| } |
| return null; |
| } |
| |
| /** |
| * <p>Finds a <code>Throwable</code> by field name.</p> |
| * |
| * @param throwable the exception to examine |
| * @param fieldName the name of the attribute to examine |
| * @return the wrapped exception, or <code>null</code> if not found |
| */ |
| private static Throwable getCauseUsingFieldName(Throwable throwable, String fieldName) { |
| Field field = null; |
| try { |
| field = throwable.getClass().getField(fieldName); |
| } catch (NoSuchFieldException ignored) { |
| // exception ignored |
| } catch (SecurityException ignored) { |
| // exception ignored |
| } |
| |
| if (field != null && Throwable.class.isAssignableFrom(field.getType())) { |
| try { |
| return (Throwable) field.get(throwable); |
| } catch (IllegalAccessException ignored) { |
| // exception ignored |
| } catch (IllegalArgumentException ignored) { |
| // exception ignored |
| } |
| } |
| return null; |
| } |
| |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Checks if the Throwable class has a <code>getCause</code> method.</p> |
| * |
| * <p>This is true for JDK 1.4 and above.</p> |
| * |
| * @return true if Throwable is nestable |
| * @since 2.0 |
| */ |
| public static boolean isThrowableNested() { |
| return THROWABLE_CAUSE_METHOD != null; |
| } |
| |
| /** |
| * <p>Checks whether this <code>Throwable</code> class can store a cause.</p> |
| * |
| * <p>This method does <b>not</b> check whether it actually does store a cause.<p> |
| * |
| * @param throwable the <code>Throwable</code> to examine, may be null |
| * @return boolean <code>true</code> if nested otherwise <code>false</code> |
| * @since 2.0 |
| */ |
| public static boolean isNestedThrowable(Throwable throwable) { |
| if (throwable == null) { |
| return false; |
| } |
| |
| if (throwable instanceof Nestable) { |
| return true; |
| } else if (throwable instanceof SQLException) { |
| return true; |
| } else if (throwable instanceof InvocationTargetException) { |
| return true; |
| } else if (isThrowableNested()) { |
| return true; |
| } |
| |
| Class cls = throwable.getClass(); |
| synchronized(CAUSE_METHOD_NAMES_LOCK) { |
| for (int i = 0, isize = CAUSE_METHOD_NAMES.length; i < isize; i++) { |
| try { |
| Method method = cls.getMethod(CAUSE_METHOD_NAMES[i], null); |
| if (method != null && Throwable.class.isAssignableFrom(method.getReturnType())) { |
| return true; |
| } |
| } catch (NoSuchMethodException ignored) { |
| // exception ignored |
| } catch (SecurityException ignored) { |
| // exception ignored |
| } |
| } |
| } |
| |
| try { |
| Field field = cls.getField("detail"); |
| if (field != null) { |
| return true; |
| } |
| } catch (NoSuchFieldException ignored) { |
| // exception ignored |
| } catch (SecurityException ignored) { |
| // exception ignored |
| } |
| |
| return false; |
| } |
| |
| //----------------------------------------------------------------------- |
| /** |
| * <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 list = getThrowableList(throwable); |
| return (Throwable[]) 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 getThrowableList(Throwable throwable) { |
| List list = new ArrayList(); |
| 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 (int i = 0; i < trace.length; i++) { |
| stream.println(trace[i]); |
| } |
| 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 (int i = 0; i < trace.length; i++) { |
| writer.println(trace[i]); |
| } |
| 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; |
| ArrayList frames = new ArrayList(); |
| List nextTrace = getStackFrameList(throwables[count - 1]); |
| for (int i = count; --i >= 0;) { |
| List 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 (String[]) frames.toArray(new String[0]); |
| } |
| |
| /** |
| * <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 causeFrames, List 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 = (String) causeFrames.get(causeFrameIndex); |
| String wrapperFrame = (String) wrapperFrames.get(wrapperFrameIndex); |
| if (causeFrame.equals(wrapperFrame)) { |
| causeFrames.remove(causeFrameIndex); |
| } |
| causeFrameIndex--; |
| wrapperFrameIndex--; |
| } |
| } |
| |
| //----------------------------------------------------------------------- |
| /** |
| * <p>A way to get the entire nested stack-trace of an throwable.</p> |
| * |
| * <p>The result of this method is highly dependent on the JDK version |
| * and whether the exceptions override printStackTrace or not.</p> |
| * |
| * @param throwable the <code>Throwable</code> to be examined |
| * @return the nested stack trace, with the root cause first |
| * @since 2.0 |
| */ |
| public static String getFullStackTrace(Throwable throwable) { |
| StringWriter sw = new StringWriter(); |
| PrintWriter pw = new PrintWriter(sw, true); |
| Throwable[] ts = getThrowables(throwable); |
| for (int i = 0; i < ts.length; i++) { |
| ts[i].printStackTrace(pw); |
| if (isNestedThrowable(ts[i])) { |
| break; |
| } |
| } |
| return sw.getBuffer().toString(); |
| } |
| |
| //----------------------------------------------------------------------- |
| /** |
| * <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> |
| * |
| * <p>Functionality shared between the |
| * <code>getStackFrames(Throwable)</code> methods of this and the |
| * {@link org.apache.commons.lang.exception.NestableDelegate} classes.</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 list = new ArrayList(); |
| while (frames.hasMoreTokens()) { |
| list.add(frames.nextToken()); |
| } |
| return toArray(list); |
| } |
| |
| /** |
| * <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 getStackFrameList(Throwable t) { |
| String stackTrace = getStackTrace(t); |
| String linebreak = SystemUtils.LINE_SEPARATOR; |
| StringTokenizer frames = new StringTokenizer(stackTrace, linebreak); |
| List list = new ArrayList(); |
| 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); |
| } |
| |
| } |