multex

Class Util

java.lang.Object

multex.Util

public class Util
extends Object

Utilities for MulTEx. Usually methods of this class should not be called by framework client code. Each exception (chain) should be reported by methods of classes Msg or Awt, or Swing.
But if the format of the mentioned reporting classes is not approriate for your purposes, then you can create your own reporting methods by the help of this MulTEx utility class.

Since:

MulTEx 6 on 2005-01-13

Author:

Christoph Knabe

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Util.InfiniteExceptionChain This exception indicates, that there is probably a cycle in an exception chain.

Field Summary

Fields

Modifier and Type	Field and Description
static char	causeIndenter The char used to indent one level of causal chain when reporting the messages or stack trace of an exception chain.
static Util.InfiniteExceptionChain	INFINITE_EXCEPTION_CHAIN Reusable instance
static String	lineSeparator Returns the line separator for the actual platform.
static String	wasCausing The string used to delimit the stack trace part of a causing exception from the following stack trace of the caused exception.

Method Summary

Modifier and Type	Method and Description
static Object[]	clone(Object[] i_array) Returns a new copy of the array or null, if null was provided
static Throwable	getCause(Throwable i_throwable) Returns the direct cause of i_throwable.
static Throwable[]	getCauses(Throwable i_throwable) Result: The directly causing Throwables of i_throwable, if there are some, otherwise null.
static Throwable	getContainedException(Throwable i_throwableChain, Class<? extends Throwable> i_expectedThrowableClass) Returns the upmost exception in i_throwableChain, which is of class i_expectedThrowableClass, helpwise null.
static int	getMaxRecursionDepth() Gets the maximum recursion depth as specified in method setMaxRecursionDepth(int).
static Throwable	getOriginalException(Throwable i_throwable)
static void	setCauseGetter(CauseGetter i_causeGetter) Sets a CauseGetter to be used by method getCause(Throwable) in order to get the cause of a Throwable object.
static void	setMaxRecursionDepth(int maxRecursionDepth) Sets the maximum depth to follow an exception chain, when calling recursively method getCause(Throwable).
static String	toString(Throwable i_throwable) For low level reporting of an exception.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

INFINITE_EXCEPTION_CHAIN

public static final Util.InfiniteExceptionChain INFINITE_EXCEPTION_CHAIN

Reusable instance

lineSeparator

public static final String lineSeparator

Returns the line separator for the actual platform. This is the line separator for the platform the Java virtual machine is running on. It is the value of the system property 'line.separator'.

wasCausing

public static final String wasCausing

The string used to delimit the stack trace part of a causing exception from the following stack trace of the caused exception.

See Also:

Constant Field Values

causeIndenter

public static final char causeIndenter

The char used to indent one level of causal chain when reporting the messages or stack trace of an exception chain.

Since:

MulTEx 6d 2006-05-16

See Also:

Constant Field Values

Method Detail

clone

public static Object[] clone(Object[] i_array)

Returns a new copy of the array or null, if null was provided

Parameters:

i_array - The array to clone

Returns:

a copy of the parameter. It is not a deep copy, but only references directly contained in the array are copied.

Since:

MulTEx 6 on 2005-01-13

setCauseGetter

public static final void setCauseGetter(CauseGetter i_causeGetter)

Sets a CauseGetter to be used by method getCause(Throwable) in order to get the cause of a Throwable object. Default is ReflectionCauseGetter

Parameters:

i_causeGetter - A CauseGetter to be used in the future

getCauses

public static final Throwable[] getCauses(Throwable i_throwable)

Result: The directly causing Throwables of i_throwable, if there are some, otherwise null. This method is better than Throwable.getCause(Throwable) in following legacy exception chaining, as it uses the ReflectionCauseGetter by default. You can replace the cause getter by method setCauseGetter(multex.CauseGetter). The cause getter is used only for getting a cause, which is returned by a method of the Throwable. All MulTEx parameters of this Throwable, which are themselves instances of Throwable, are returned, too.

Parameters:

i_throwable - The root of a Throwable tree

Returns:

all Throwable objects directly contained in i_throwable either as cause or as parameters

getMaxRecursionDepth

public static final int getMaxRecursionDepth()

Gets the maximum recursion depth as specified in method setMaxRecursionDepth(int).

Returns:

The current maximum recursion depth

Since:

MulTEx 8.3 as of 2011-03-25

setMaxRecursionDepth

public static void setMaxRecursionDepth(int maxRecursionDepth)
                                 throws IllegalArgumentException

Sets the maximum depth to follow an exception chain, when calling recursively method getCause(Throwable). Will be used by _appendCompactStackTraceRecursively(StringBuffer, Throwable, StackTraceElement[], int), MsgText._appendMessageTreeRecursively(StringBuffer, Throwable, java.util.ResourceBundle, String, int) and should be respected by everyone following an exception chain by calling method getCause(Throwable).

Parameters:

maxRecursionDepth - May range from 5 to 100. Default is 10.

Throws:

IllegalArgumentException - argument outside of range 5...100

Since:

8.3 as of 2011-03-25

getCause

public static final Throwable getCause(Throwable i_throwable)

Returns the direct cause of i_throwable.

Parameters:

i_throwable - The Throwable which may begin a chain of Throwables.

Returns:

The directly causing Throwable of i_throwable, if there is one, otherwise null. This method is better than Throwable.getCause(Throwable) in following legacy exception chaining, as it uses the ReflectionCauseGetter by default. You can replace the cause getter by method setCauseGetter(multex.CauseGetter). Tries to avoid a cause cycle by returning null, if a direct cycle is detected.

getContainedException

public static Throwable getContainedException(Throwable i_throwableChain,
                                              Class<? extends Throwable> i_expectedThrowableClass)

Returns the upmost exception in i_throwableChain, which is of class i_expectedThrowableClass, helpwise null. Usage e.g. for a FieldValueExc, which is thrown from the business logic layer to the user interface layer, wrapped some times on this way, but should trigger a uniform reaction on the user interface layer (Marking the named form field as erroneous, and issuing its error message).

Parameters:

i_throwableChain - a chain of Throwables

i_expectedThrowableClass - the class an instance of which we search

Returns:

INFINITE_EXCEPTION_CHAIN if the exception chain to be followed is longer than getMaxRecursionDepth().

See Also:

setMaxRecursionDepth(int)

getOriginalException

public static final Throwable getOriginalException(Throwable i_throwable)

Parameters:

i_throwable - A Throwable chain.

Returns:

The deepest Throwable object, which indirectly caused the program to throw i_throwable, if there is one, otherwise i_throwable itself. If i_throwable is null, the result will be null, too. Returns INFINITE_EXCEPTION_CHAIN if the exception chain to be followed is longer than getMaxRecursionDepth().

See Also:

getCause(Throwable), setMaxRecursionDepth(int)

toString

public static String toString(Throwable i_throwable)

For low level reporting of an exception. Preferably use this toString(), than the JDK-provided throwable.toString(). The JDK reports in the format package.subpackage.ClassName: throwable.getMessage(), which is suitably redefined for any MultexException, too.

But some legacy exceptions suppress the class name or the message of the exception. In order to obtain all relevant information of an exception we use our own toString(), which augments the result of .toString() by the class name and the message of the exception, if needed.

Parameters:

i_throwable - The Throwable which is to be converted to a String

Returns:

The result of converting the Throwable to a String.