Package slash.common.helpers

Class ExceptionHelper

java.lang.Object

slash.common.helpers.ExceptionHelper

public class ExceptionHelper
extends Object

Provides exception helpers

Author:

Christian Pesch

Constructor Summary

Constructors

Constructor	Description
ExceptionHelper()

Method Summary

Modifier and Type	Method	Description
static List<Throwable>	getCauseChain(Throwable throwable)	Walks the cause chain from throwable to the deepest cause and returns every distinct throwable on the way, outermost first.
static String	getLocalizedMessage(Throwable throwable)
static String	getLocalizedMessage(Throwable throwable, String url)	Like getLocalizedMessage(Throwable), but names the host of the given url, if any.
static String	getMessageWithCauses(Throwable throwable)	Renders the throwable and its whole cause chain as one line, e.g.
static Throwable	getRootCause(Throwable throwable)	Walks the cause chain to the deepest cause.
static boolean	isComputerOffline(Throwable throwable)
static String	printStackTrace(Throwable throwable)

Methods inherited from class java.lang.Object

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

Constructor Details

ExceptionHelper

public ExceptionHelper()

Method Details

isComputerOffline

public static boolean isComputerOffline(Throwable throwable)

getLocalizedMessage

public static String getLocalizedMessage(Throwable throwable)

getLocalizedMessage

public static String getLocalizedMessage(Throwable throwable,
 String url)

Like getLocalizedMessage(Throwable), but names the host of the given url, if any. Only an unreachable host is reported as offline: a server that accepts the connection and then does not answer in time, or fails the TLS handshake, is not the computer's fault.

getCauseChain

public static List<Throwable> getCauseChain(Throwable throwable)

Walks the cause chain from throwable to the deepest cause and returns every distinct throwable on the way, outermost first.

The walk is cycle-safe: a throwable is only visited once (identity-based), so a self-referential (A -> A) or looping (A -> B -> A) chain, which a naive getCause() loop would follow forever, terminates. This is the single cause-chain traversal every other helper here (and DiagnosticReport) shares.

getRootCause

public static Throwable getRootCause(Throwable throwable)

Walks the cause chain to the deepest cause. A wrapper like ExceptionInInitializerError or InvocationTargetException carries the real fault (e.g. a NoClassDefFoundError for a missing JDK module) as its cause; this returns that fault instead of the wrapper. Cycle-safe via getCauseChain(java.lang.Throwable).

getMessageWithCauses

public static String getMessageWithCauses(Throwable throwable)

Renders the throwable and its whole cause chain as one line, e.g. "ExceptionInInitializerError caused by NoClassDefFoundError: jdk/net/Sockets". Surfaces the underlying fault that a single getMessage() hides -- the outermost message is often a generic "Could not initialize class ...". Cycle-safe via getCauseChain(java.lang.Throwable).

printStackTrace

public static String printStackTrace(Throwable throwable)