Package de.aristaflow.ilm.ws.rest.base.service

Class ExceptionHandling

java.lang.Object

de.aristaflow.ilm.ws.rest.base.service.ExceptionHandling

All Implemented Interfaces:

de.aristaflow.adept2.base.communication.rest.ExceptionHandler

public class ExceptionHandling
extends Object
implements de.aristaflow.adept2.base.communication.rest.ExceptionHandler

This class implements ExceptionHandler an thus provides the means for handling exceptions appropriately. This is, exceptions are wrapped the status of stack suppression is set and server log IDs are created as required.

Suppression of server stacks is set via configuration of the communication service and can be overridden per request which is retrieved from the RequestHandler.

UUIDs identifying the log messages for a specific exception will have the current timestamp as most significant bytes. This should also be used as time for the log messages to allow for easily finding a log message.
Since unexpected exceptions are logged before they are wrapped (and the logging class cannot wrap them), the created server log ID needs to be stored until these exceptions are wrapped. This is done using a Cache. Although each created server log ID eventually gets used when wrapping the corresponding exceptions, exceptions occurring while handling such an exception may prevent this. The usage of Cache ensures that no UUID is kept forever.

Nested Class Summary

Nested classes/interfaces inherited from interface de.aristaflow.adept2.base.communication.rest.ExceptionHandler

de.aristaflow.adept2.base.communication.rest.ExceptionHandler.ExpectedException

Field Summary

Fields

Modifier and Type	Field	Description
protected final Logger	logger	The logger with which to log exceptions that have not been logged before.
protected final Random	random	A random for generating the least significant bytes for the unique server log ID.
protected de.aristaflow.adept2.base.communication.rest.RequestHandler	reqHandler	The request handler to get the header data whether to keep the server stack even if the communication service should suppress the stacks.
protected final Cache<Throwable,UUID>	serverLogIds	The cache keeping the created server log IDs for unexpected exceptions until these exceptions are wrapped eventually.
protected final boolean	suppressServerStack	Whether the communication service is set to suppress the exception stacks so that they do not reach the caller.

Constructor Summary

Constructors

Constructor	Description
ExceptionHandling(boolean suppressServerStack, de.aristaflow.adept2.base.communication.rest.RequestHandler reqHandler, LogService logService)	Creates a new exception handling with the designated fields.

Method Summary

Modifier and Type	Method	Description
protected UUID	createServerLogId()	Creates a unique ID to be set in the message log and in the exception that is sent to the client.
UUID	getServerLogId(Throwable cause)
de.aristaflow.adept2.base.communication.rest.ExceptionHandler.ExpectedException	wrapExpectedException(Throwable cause, jakarta.ws.rs.core.Response.Status status)
IlmException	wrapUnexpectedException(Throwable cause)

Methods inherited from class java.lang.Object

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

Field Details

logger

protected final Logger logger

The logger with which to log exceptions that have not been logged before.

random

protected final Random random

A random for generating the least significant bytes for the unique server log ID.

serverLogIds

protected final Cache<Throwable,UUID> serverLogIds

The cache keeping the created server log IDs for unexpected exceptions until these exceptions are wrapped eventually.

suppressServerStack

protected final boolean suppressServerStack

Whether the communication service is set to suppress the exception stacks so that they do not reach the caller.

reqHandler

protected de.aristaflow.adept2.base.communication.rest.RequestHandler reqHandler

The request handler to get the header data whether to keep the server stack even if the communication service should suppress the stacks.

Constructor Details

ExceptionHandling

public ExceptionHandling(boolean suppressServerStack,
 de.aristaflow.adept2.base.communication.rest.RequestHandler reqHandler,
 LogService logService)

Creates a new exception handling with the designated fields.

Parameters:

suppressServerStack - Whether the communication service is set to suppress the exception stacks so that they do not reach the caller.

reqHandler - The request handler to get the header data whether to keep the server stack even if the communication service should suppress the stacks.

logService - The log service to retrieve the logger with which to log exceptions that have not been logged before.

Method Details

wrapExpectedException

public de.aristaflow.adept2.base.communication.rest.ExceptionHandler.ExpectedException wrapExpectedException(Throwable cause,
 jakarta.ws.rs.core.Response.Status status)

Specified by:

wrapExpectedException in interface de.aristaflow.adept2.base.communication.rest.ExceptionHandler

wrapUnexpectedException

public IlmException wrapUnexpectedException(Throwable cause)

Specified by:

wrapUnexpectedException in interface de.aristaflow.adept2.base.communication.rest.ExceptionHandler

getServerLogId

public UUID getServerLogId(Throwable cause)

Specified by:

getServerLogId in interface de.aristaflow.adept2.base.communication.rest.ExceptionHandler

createServerLogId

protected UUID createServerLogId()

Creates a unique ID to be set in the message log and in the exception that is sent to the client. For easier finding a message, the most significant bytes of the UUID correspond to the time of the corresponding log message.

Returns:

A unique ID to be set in the message log and in the exception that is sent to the client.