001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017 package org.apache.commons.lang3.exception;
018
019 import java.util.List;
020 import java.util.Set;
021
022 import org.apache.commons.lang3.tuple.Pair;
023
024 /**
025 * Allows the storage and retrieval of contextual information based on label-value
026 * pairs for exceptions.
027 * <p>
028 * Implementations are expected to manage the pairs in a list-style collection
029 * that keeps the pairs in the sequence of their addition.
030 * </p>
031 *
032 * @see ContextedException
033 * @see ContextedRuntimeException
034 * @since 3.0
035 */
036 public interface ExceptionContext {
037
038 /**
039 * Adds a contextual label-value pair into this context.
040 * <p>
041 * The pair will be added to the context, independently of an already
042 * existing pair with the same label.
043 * </p>
044 *
045 * @param label the label of the item to add, {@code null} not recommended
046 * @param value the value of item to add, may be {@code null}
047 * @return {@code this}, for method chaining, not {@code null}
048 */
049 public ExceptionContext addContextValue(String label, Object value);
050
051 /**
052 * Sets a contextual label-value pair into this context.
053 * <p>
054 * The pair will be added normally, but any existing label-value pair with
055 * the same label is removed from the context.
056 * </p>
057 *
058 * @param label the label of the item to add, {@code null} not recommended
059 * @param value the value of item to add, may be {@code null}
060 * @return {@code this}, for method chaining, not {@code null}
061 */
062 public ExceptionContext setContextValue(String label, Object value);
063
064 /**
065 * Retrieves all the contextual data values associated with the label.
066 *
067 * @param label the label to get the contextual values for, may be {@code null}
068 * @return the contextual values associated with the label, never {@code null}
069 */
070 public List<Object> getContextValues(String label);
071
072 /**
073 * Retrieves the first available contextual data value associated with the label.
074 *
075 * @param label the label to get the contextual value for, may be {@code null}
076 * @return the first contextual value associated with the label, may be {@code null}
077 */
078 public Object getFirstContextValue(String label);
079
080 /**
081 * Retrieves the full set of labels defined in the contextual data.
082 *
083 * @return the set of labels, not {@code null}
084 */
085 public Set<String> getContextLabels();
086
087 /**
088 * Retrieves the full list of label-value pairs defined in the contextual data.
089 *
090 * @return the list of pairs, not {@code null}
091 */
092 public List<Pair<String, Object>> getContextEntries();
093
094 /**
095 * Gets the contextualized error message based on a base message.
096 * This will add the context label-value pairs to the message.
097 *
098 * @param baseMessage the base exception message <b>without</b> context information appended
099 * @return the exception message <b>with</b> context information appended, not {@code null}
100 */
101 public String getFormattedExceptionMessage(String baseMessage);
102
103 }