org.apache.commons.lang3.exception.ContextedException Maven / Gradle / Ivy
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/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.lang3.exception;
import java.util.List;
import java.util.Set;
import org.apache.commons.lang3.tuple.Pair;
/**
*
* An exception that provides an easy and safe way to add contextual information.
*
* An exception trace itself is often insufficient to provide rapid diagnosis of the issue.
* Frequently what is needed is a select few pieces of local contextual data.
* Providing this data is tricky however, due to concerns over formatting and nulls.
*
* The contexted exception approach allows the exception to be created together with a
* list of context label-value pairs. This additional information is automatically included in
* the message and printed stack trace.
*
* An unchecked version of this exception is provided by ContextedRuntimeException.
*
*
* To use this class write code as follows:
*
*
* try {
* ...
* } catch (Exception e) {
* throw new ContextedException("Error posting account transaction", e)
* .addContextValue("Account Number", accountNumber)
* .addContextValue("Amount Posted", amountPosted)
* .addContextValue("Previous Balance", previousBalance)
* }
* }
*
*
* or improve diagnose data at a higher level:
*
*
* try {
* ...
* } catch (ContextedException e) {
* throw e.setContextValue("Transaction Id", transactionId);
* } catch (Exception e) {
* if (e instanceof ExceptionContext) {
* e.setContextValue("Transaction Id", transactionId);
* }
* throw e;
* }
* }
*
*
* The output in a printStacktrace() (which often is written to a log) would look something like the following:
*
*
* org.apache.commons.lang3.exception.ContextedException: java.lang.Exception: Error posting account transaction
* Exception Context:
* [1:Account Number=null]
* [2:Amount Posted=100.00]
* [3:Previous Balance=-2.17]
* [4:Transaction Id=94ef1d15-d443-46c4-822b-637f26244899]
*
* ---------------------------------
* at org.apache.commons.lang3.exception.ContextedExceptionTest.testAddValue(ContextedExceptionTest.java:88)
* ..... (rest of trace)
*
*
* @see ContextedRuntimeException
* @since 3.0
*/
public class ContextedException extends Exception implements ExceptionContext {
/** The serialization version. */
private static final long serialVersionUID = 20110706L;
/** The context where the data is stored. */
private final ExceptionContext exceptionContext;
/**
* Instantiates ContextedException without message or cause.
*
* The context information is stored using a default implementation.
*/
public ContextedException() {
super();
exceptionContext = new DefaultExceptionContext();
}
/**
* Instantiates ContextedException with message, but without cause.
*
* The context information is stored using a default implementation.
*
* @param message the exception message, may be null
*/
public ContextedException(final String message) {
super(message);
exceptionContext = new DefaultExceptionContext();
}
/**
* Instantiates ContextedException with cause, but without message.
*
* The context information is stored using a default implementation.
*
* @param cause the underlying cause of the exception, may be null
*/
public ContextedException(final Throwable cause) {
super(cause);
exceptionContext = new DefaultExceptionContext();
}
/**
* Instantiates ContextedException with cause and message.
*
* The context information is stored using a default implementation.
*
* @param message the exception message, may be null
* @param cause the underlying cause of the exception, may be null
*/
public ContextedException(final String message, final Throwable cause) {
super(message, cause);
exceptionContext = new DefaultExceptionContext();
}
/**
* Instantiates ContextedException with cause, message, and ExceptionContext.
*
* @param message the exception message, may be null
* @param cause the underlying cause of the exception, may be null
* @param context the context used to store the additional information, null uses default implementation
*/
public ContextedException(final String message, final Throwable cause, ExceptionContext context) {
super(message, cause);
if (context == null) {
context = new DefaultExceptionContext();
}
exceptionContext = context;
}
//-----------------------------------------------------------------------
/**
* Adds information helpful to a developer in diagnosing and correcting the problem.
* For the information to be meaningful, the value passed should have a reasonable
* toString() implementation.
* Different values can be added with the same label multiple times.
*
* Note: This exception is only serializable if the object added is serializable.
*
*
* @param label a textual label associated with information, {@code null} not recommended
* @param value information needed to understand exception, may be {@code null}
* @return {@code this}, for method chaining, not {@code null}
*/
@Override
public ContextedException addContextValue(final String label, final Object value) {
exceptionContext.addContextValue(label, value);
return this;
}
/**
* Sets information helpful to a developer in diagnosing and correcting the problem.
* For the information to be meaningful, the value passed should have a reasonable
* toString() implementation.
* Any existing values with the same labels are removed before the new one is added.
*
* Note: This exception is only serializable if the object added as value is serializable.
*
*
* @param label a textual label associated with information, {@code null} not recommended
* @param value information needed to understand exception, may be {@code null}
* @return {@code this}, for method chaining, not {@code null}
*/
@Override
public ContextedException setContextValue(final String label, final Object value) {
exceptionContext.setContextValue(label, value);
return this;
}
/**
* {@inheritDoc}
*/
@Override
public List