public class ThrowableAnalyzer
extends java.lang.Object
Throwable
instances.
Can be subclassed to customize its behavior.Modifier and Type | Field and Description |
---|---|
static ThrowableCauseExtractor |
DEFAULT_EXTRACTOR
Default extractor for
Throwable instances. |
static ThrowableCauseExtractor |
INVOCATIONTARGET_EXTRACTOR
Default extractor for
InvocationTargetException instances. |
Constructor and Description |
---|
ThrowableAnalyzer()
Creates a new
ThrowableAnalyzer instance. |
Modifier and Type | Method and Description |
---|---|
java.lang.Throwable[] |
determineCauseChain(java.lang.Throwable throwable)
Determines the cause chain of the provided
Throwable . |
java.lang.Throwable |
getFirstThrowableOfType(java.lang.Class<? extends java.lang.Throwable> throwableType,
java.lang.Throwable[] chain)
Returns the first throwable from the passed in array that is assignable to the
provided type.
|
protected void |
initExtractorMap()
Initializes associations between
Throwable s and
ThrowableCauseExtractor s. |
protected void |
registerExtractor(java.lang.Class<? extends java.lang.Throwable> throwableType,
ThrowableCauseExtractor extractor)
Registers a
ThrowableCauseExtractor for the specified type. |
static void |
verifyThrowableHierarchy(java.lang.Throwable throwable,
java.lang.Class<? extends java.lang.Throwable> expectedBaseType)
Verifies that the provided throwable is a valid subclass of the provided type (or
of the type itself).
|
public static final ThrowableCauseExtractor DEFAULT_EXTRACTOR
Throwable
instances.Throwable.getCause()
public static final ThrowableCauseExtractor INVOCATIONTARGET_EXTRACTOR
InvocationTargetException
instances.InvocationTargetException.getTargetException()
public ThrowableAnalyzer()
ThrowableAnalyzer
instance.protected final void registerExtractor(java.lang.Class<? extends java.lang.Throwable> throwableType, ThrowableCauseExtractor extractor)
ThrowableCauseExtractor
for the specified type. Can be
used in subclasses overriding initExtractorMap()
.throwableType
- the type (has to be a subclass of Throwable
)extractor
- the associated ThrowableCauseExtractor
(not
null
)java.lang.IllegalArgumentException
- if one of the arguments is invalidprotected void initExtractorMap()
Throwable
s and
ThrowableCauseExtractor
s. The default implementation performs the
following registrations:
DEFAULT_EXTRACTOR
for Throwable
INVOCATIONTARGET_EXTRACTOR
for InvocationTargetException
Note: An extractor registered for a specific type is applicable for that type
and all subtypes thereof. However, extractors registered to more specific
types are guaranteed to be resolved first. So in the default case
InvocationTargetExceptions will be handled by INVOCATIONTARGET_EXTRACTOR
while all other throwables are handled by DEFAULT_EXTRACTOR
.
public final java.lang.Throwable[] determineCauseChain(java.lang.Throwable throwable)
Throwable
. The returned
array contains all throwables extracted from the stacktrace, using the registered
extractors
. The elements of the array are ordered:
The first element is the passed in throwable itself. The following elements appear
in their order downward the stacktrace.
Note: If no ThrowableCauseExtractor
is registered for this instance then
the returned array will always only contain the passed in throwable.
throwable
- the Throwable
to analyzejava.lang.IllegalArgumentException
- if the throwable is null
initExtractorMap()
public final java.lang.Throwable getFirstThrowableOfType(java.lang.Class<? extends java.lang.Throwable> throwableType, java.lang.Throwable[] chain)
If the passed in array is null or empty this method returns null
.
throwableType
- the type to look forchain
- the array (will be processed in element order)Throwable
, null
if not foundjava.lang.IllegalArgumentException
- if the provided type is null
or no
subclass of Throwable
public static void verifyThrowableHierarchy(java.lang.Throwable throwable, java.lang.Class<? extends java.lang.Throwable> expectedBaseType)
expectdBaseType
is null
, no check
will be performed.
Can be used for verification purposes in implementations of
extractors
.
throwable
- the Throwable
to checkexpectedBaseType
- the type to check againstjava.lang.IllegalArgumentException
- if throwable
is either
null
or its type is not assignable to expectedBaseType