一、前言

关于cayenne包中org.apache.commons.lang.exception.ExceptionUtils异常处理工具类，获取白名单异常序列、将异常堆栈信息转为字符串、将异常信息匹配为名单定义格式进行输出、判断异常是否指定class对象抛出等。

二、源码说明

package org.apache.commons.lang.exception;@b@@b@import java.io.PrintStream;@b@import java.io.PrintWriter;@b@import java.io.StringWriter;@b@import java.lang.reflect.Field;@b@import java.lang.reflect.InvocationTargetException;@b@import java.lang.reflect.Method;@b@import java.sql.SQLException;@b@import java.util.ArrayList;@b@import java.util.Arrays;@b@import java.util.LinkedList;@b@import java.util.List;@b@import java.util.StringTokenizer;@b@import org.apache.commons.lang.ArrayUtils;@b@import org.apache.commons.lang.StringUtils;@b@import org.apache.commons.lang.SystemUtils;@b@@b@public class ExceptionUtils@b@{@b@  static final String WRAPPED_MARKER = " [wrapped] ";@b@  private static String[] CAUSE_METHOD_NAMES;@b@  private static final Method THROWABLE_CAUSE_METHOD;@b@@b@  static@b@  {@b@    Method getCauseMethod;@b@    CAUSE_METHOD_NAMES = new String[] { @b@      "getCause", @b@      "getNextException", @b@      "getTargetException", @b@      "getException", @b@      "getSourceException", @b@      "getRootCause", @b@      "getCausedByException", @b@      "getNested", @b@      "getLinkedException", @b@      "getNestedException", @b@      "getLinkedCause", @b@      "getThrowable" };@b@    try@b@    {@b@      getCauseMethod = Throwable.class.getMethod("getCause", null);@b@    } catch (Exception localException) {@b@      getCauseMethod = null;@b@    }@b@    THROWABLE_CAUSE_METHOD = getCauseMethod;@b@  }@b@@b@  public static void addCauseMethodName(String methodName)@b@  {@b@    if ((StringUtils.isNotEmpty(methodName)) && (!(isCauseMethodName(methodName)))) {@b@      List list = getCauseMethodNameList();@b@      if (list.add(methodName))@b@        CAUSE_METHOD_NAMES = toArray(list);@b@    }@b@  }@b@@b@  public static Throwable getCause(Throwable throwable)@b@  {@b@    return getCause(throwable, CAUSE_METHOD_NAMES);@b@  }@b@@b@  public static Throwable getCause(Throwable throwable, String[] methodNames)@b@  {@b@    if (throwable == null)@b@      return null;@b@@b@    Throwable cause = getCauseUsingWellKnownTypes(throwable);@b@    if (cause == null) {@b@      if (methodNames == null)@b@        methodNames = CAUSE_METHOD_NAMES;@b@@b@      for (int i = 0; i < methodNames.length; ++i) {@b@        String methodName = methodNames[i];@b@        if (methodName != null) {@b@          cause = getCauseUsingMethodName(throwable, methodName);@b@          if (cause != null)@b@            break;@b@        }@b@@b@      }@b@@b@      if (cause == null)@b@        cause = getCauseUsingFieldName(throwable, "detail");@b@    }@b@@b@    return cause;@b@  }@b@@b@  private static ArrayList getCauseMethodNameList()@b@  {@b@    return new ArrayList(Arrays.asList(CAUSE_METHOD_NAMES));@b@  }@b@@b@  private static Throwable getCauseUsingFieldName(Throwable throwable, String fieldName)@b@  {@b@    Field field = null;@b@    try {@b@      field = throwable.getClass().getField(fieldName);@b@    } catch (NoSuchFieldException localNoSuchFieldException) {@b@    }@b@    catch (SecurityException localSecurityException) {@b@    }@b@    if ((field != null) && (Throwable.class.isAssignableFrom(field.getType())))@b@      try {@b@        return ((Throwable)field.get(throwable));@b@      } catch (IllegalAccessException localIllegalAccessException) {@b@      }@b@      catch (IllegalArgumentException localIllegalArgumentException) {@b@      }@b@    return null;@b@  }@b@@b@  private static Throwable getCauseUsingMethodName(Throwable throwable, String methodName)@b@  {@b@    Method method = null;@b@    try {@b@      method = throwable.getClass().getMethod(methodName, null);@b@    } catch (NoSuchMethodException localNoSuchMethodException) {@b@    }@b@    catch (SecurityException localSecurityException) {@b@    }@b@    if ((method != null) && (Throwable.class.isAssignableFrom(method.getReturnType())))@b@      try {@b@        return ((Throwable)method.invoke(throwable, ArrayUtils.EMPTY_OBJECT_ARRAY));@b@      } catch (IllegalAccessException localIllegalAccessException) {@b@      } catch (IllegalArgumentException localIllegalArgumentException) {@b@      }@b@      catch (InvocationTargetException localInvocationTargetException) {@b@      }@b@    return null;@b@  }@b@@b@  private static Throwable getCauseUsingWellKnownTypes(Throwable throwable)@b@  {@b@    if (throwable instanceof Nestable)@b@      return ((Nestable)throwable).getCause();@b@    if (throwable instanceof SQLException)@b@      return ((SQLException)throwable).getNextException();@b@    if (throwable instanceof InvocationTargetException)@b@      return ((InvocationTargetException)throwable).getTargetException();@b@@b@    return null;@b@  }@b@@b@  public static String getFullStackTrace(Throwable throwable)@b@  {@b@    StringWriter sw = new StringWriter();@b@    PrintWriter pw = new PrintWriter(sw, true);@b@    Throwable[] ts = getThrowables(throwable);@b@    for (int i = 0; i < ts.length; ++i) {@b@      ts[i].printStackTrace(pw);@b@      if (isNestedThrowable(ts[i]))@b@        break;@b@    }@b@@b@    return sw.getBuffer().toString();@b@  }@b@@b@  public static Throwable getRootCause(Throwable throwable)@b@  {@b@    Throwable cause = getCause(throwable);@b@    if (cause != null) {@b@      throwable = cause;@b@      while ((throwable = getCause(throwable)) != null)@b@        cause = throwable;@b@    }@b@@b@    return cause;@b@  }@b@@b@  public static String[] getRootCauseStackTrace(Throwable throwable)@b@  {@b@    if (throwable == null)@b@      return ArrayUtils.EMPTY_STRING_ARRAY;@b@@b@    Throwable[] throwables = getThrowables(throwable);@b@    int count = throwables.length;@b@    ArrayList frames = new ArrayList();@b@    List nextTrace = getStackFrameList(throwables[(count - 1)]);@b@    int i = count; while (--i >= 0) {@b@      List trace = nextTrace;@b@      if (i != 0) {@b@        nextTrace = getStackFrameList(throwables[(i - 1)]);@b@        removeCommonFrames(trace, nextTrace);@b@      }@b@      if (i == count - 1)@b@        frames.add(throwables[i].toString());@b@      else@b@        frames.add(" [wrapped] " + throwables[i].toString());@b@@b@      for (int j = 0; j < trace.size(); ++j)@b@        frames.add(trace.get(j));@b@    }@b@@b@    return ((String[])frames.toArray(new String[0]));@b@  }@b@@b@  static List getStackFrameList(Throwable t)@b@  {@b@    String stackTrace = getStackTrace(t);@b@    String linebreak = SystemUtils.LINE_SEPARATOR;@b@    StringTokenizer frames = new StringTokenizer(stackTrace, linebreak);@b@    List list = new LinkedList();@b@    boolean traceStarted = false;@b@    while (frames.hasMoreTokens()) {@b@      String token = frames.nextToken();@b@@b@      int at = token.indexOf("at");@b@      if ((at != -1) && (token.substring(0, at).trim().length() == 0)) {@b@        traceStarted = true;@b@        list.add(token);@b@      } else if (traceStarted) {@b@        break;@b@      }@b@    }@b@    return list;@b@  }@b@@b@  static String[] getStackFrames(String stackTrace)@b@  {@b@    String linebreak = SystemUtils.LINE_SEPARATOR;@b@    StringTokenizer frames = new StringTokenizer(stackTrace, linebreak);@b@    List list = new LinkedList();@b@    while (frames.hasMoreTokens())@b@      list.add(frames.nextToken());@b@@b@    return toArray(list);@b@  }@b@@b@  public static String[] getStackFrames(Throwable throwable)@b@  {@b@    if (throwable == null)@b@      return ArrayUtils.EMPTY_STRING_ARRAY;@b@@b@    return getStackFrames(getStackTrace(throwable));@b@  }@b@@b@  public static String getStackTrace(Throwable throwable)@b@  {@b@    StringWriter sw = new StringWriter();@b@    PrintWriter pw = new PrintWriter(sw, true);@b@    throwable.printStackTrace(pw);@b@    return sw.getBuffer().toString();@b@  }@b@@b@  public static int getThrowableCount(Throwable throwable)@b@  {@b@    int count = 0;@b@    while (throwable != null) {@b@      ++count;@b@      throwable = getCause(throwable);@b@    }@b@    return count;@b@  }@b@@b@  public static Throwable[] getThrowables(Throwable throwable)@b@  {@b@    List list = new ArrayList();@b@    while (throwable != null) {@b@      list.add(throwable);@b@      throwable = getCause(throwable);@b@    }@b@    return ((Throwable[])list.toArray(new Throwable[list.size()]));@b@  }@b@@b@  private static int indexOf(Throwable throwable, Class type, int fromIndex, boolean subclass)@b@  {@b@    int i;@b@    if ((throwable == null) || (type == null))@b@      return -1;@b@@b@    if (fromIndex < 0)@b@      fromIndex = 0;@b@@b@    Throwable[] throwables = getThrowables(throwable);@b@    if (fromIndex >= throwables.length)@b@      return -1;@b@@b@    if (subclass)@b@      for (i = fromIndex; i < throwables.length; ++i)@b@        if (type.isAssignableFrom(throwables[i].getClass()))@b@          return i;@b@@b@@b@    else@b@      for (i = fromIndex; i < throwables.length; ++i)@b@        if (type.equals(throwables[i].getClass()))@b@          return i;@b@@b@@b@@b@    return -1;@b@  }@b@@b@  public static int indexOfThrowable(Throwable throwable, Class clazz)@b@  {@b@    return indexOf(throwable, clazz, 0, false);@b@  }@b@@b@  public static int indexOfThrowable(Throwable throwable, Class clazz, int fromIndex)@b@  {@b@    return indexOf(throwable, clazz, fromIndex, false);@b@  }@b@@b@  public static int indexOfType(Throwable throwable, Class type)@b@  {@b@    return indexOf(throwable, type, 0, true);@b@  }@b@@b@  public static int indexOfType(Throwable throwable, Class type, int fromIndex)@b@  {@b@    return indexOf(throwable, type, fromIndex, true);@b@  }@b@@b@  public static boolean isCauseMethodName(String methodName)@b@  {@b@    return (ArrayUtils.indexOf(CAUSE_METHOD_NAMES, methodName) >= 0);@b@  }@b@@b@  public static boolean isNestedThrowable(Throwable throwable)@b@  {@b@    if (throwable == null) {@b@      return false;@b@    }@b@@b@    if (throwable instanceof Nestable)@b@      return true;@b@    if (throwable instanceof SQLException)@b@      return true;@b@    if (throwable instanceof InvocationTargetException)@b@      return true;@b@    if (isThrowableNested()) {@b@      return true;@b@    }@b@@b@    Class cls = throwable.getClass();@b@    int i = 0; label115: for (int isize = CAUSE_METHOD_NAMES.length; i < isize; ++i)@b@      try {@b@        Method method = cls.getMethod(CAUSE_METHOD_NAMES[i], null);@b@        if ((method == null) || (!(Throwable.class.isAssignableFrom(method.getReturnType())))) break label115;@b@        return true;@b@      }@b@      catch (NoSuchMethodException localNoSuchMethodException)@b@      {@b@      }@b@      catch (SecurityException localSecurityException1) {@b@      }@b@    try {@b@      Field field = cls.getField("detail");@b@      if (field == null) break label143;@b@      return true;@b@    }@b@    catch (NoSuchFieldException localNoSuchFieldException) {@b@    }@b@    catch (SecurityException localSecurityException2) {@b@    }@b@    label143: return false;@b@  }@b@@b@  public static boolean isThrowableNested()@b@  {@b@    return (THROWABLE_CAUSE_METHOD != null);@b@  }@b@@b@  public static void printRootCauseStackTrace(Throwable throwable)@b@  {@b@    printRootCauseStackTrace(throwable, System.err);@b@  }@b@@b@  public static void printRootCauseStackTrace(Throwable throwable, PrintStream stream)@b@  {@b@    if (throwable == null)@b@      return;@b@@b@    if (stream == null)@b@      throw new IllegalArgumentException("The PrintStream must not be null");@b@@b@    String[] trace = getRootCauseStackTrace(throwable);@b@    for (int i = 0; i < trace.length; ++i)@b@      stream.println(trace[i]);@b@@b@    stream.flush();@b@  }@b@@b@  public static void printRootCauseStackTrace(Throwable throwable, PrintWriter writer)@b@  {@b@    if (throwable == null)@b@      return;@b@@b@    if (writer == null)@b@      throw new IllegalArgumentException("The PrintWriter must not be null");@b@@b@    String[] trace = getRootCauseStackTrace(throwable);@b@    for (int i = 0; i < trace.length; ++i)@b@      writer.println(trace[i]);@b@@b@    writer.flush();@b@  }@b@@b@  public static void removeCauseMethodName(String methodName)@b@  {@b@    if (StringUtils.isNotEmpty(methodName)) {@b@      List list = getCauseMethodNameList();@b@      if (list.remove(methodName))@b@        CAUSE_METHOD_NAMES = toArray(list);@b@    }@b@  }@b@@b@  public static void removeCommonFrames(List causeFrames, List wrapperFrames)@b@  {@b@    if ((causeFrames == null) || (wrapperFrames == null))@b@      throw new IllegalArgumentException("The List must not be null");@b@@b@    int causeFrameIndex = causeFrames.size() - 1;@b@    int wrapperFrameIndex = wrapperFrames.size() - 1;@b@    while ((causeFrameIndex >= 0) && (wrapperFrameIndex >= 0))@b@    {@b@      String causeFrame = (String)causeFrames.get(causeFrameIndex);@b@      String wrapperFrame = (String)wrapperFrames.get(wrapperFrameIndex);@b@      if (causeFrame.equals(wrapperFrame))@b@        causeFrames.remove(causeFrameIndex);@b@@b@      --causeFrameIndex;@b@      --wrapperFrameIndex;@b@    }@b@  }@b@@b@  private static String[] toArray(List list)@b@  {@b@    return ((String[])list.toArray(new String[list.size()]));@b@  }@b@}