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 */ 017package org.apache.commons.lang3.exception; 018 019import java.io.Serializable; 020import java.util.ArrayList; 021import java.util.List; 022import java.util.Set; 023import java.util.stream.Collectors; 024import java.util.stream.Stream; 025 026import org.apache.commons.lang3.StringUtils; 027import org.apache.commons.lang3.tuple.ImmutablePair; 028import org.apache.commons.lang3.tuple.Pair; 029 030/** 031 * Default implementation of the context storing the label-value pairs for contexted exceptions. 032 * <p> 033 * This implementation is serializable, however this is dependent on the values that 034 * are added also being serializable. 035 * </p> 036 * 037 * @see ContextedException 038 * @see ContextedRuntimeException 039 * @since 3.0 040 */ 041public class DefaultExceptionContext implements ExceptionContext, Serializable { 042 043 /** The serialization version. */ 044 private static final long serialVersionUID = 20110706L; 045 046 /** The list storing the label-data pairs. */ 047 private final List<Pair<String, Object>> contextValues = new ArrayList<>(); 048 049 /** 050 * {@inheritDoc} 051 */ 052 @Override 053 public DefaultExceptionContext addContextValue(final String label, final Object value) { 054 contextValues.add(new ImmutablePair<>(label, value)); 055 return this; 056 } 057 058 /** 059 * {@inheritDoc} 060 */ 061 @Override 062 public List<Pair<String, Object>> getContextEntries() { 063 return contextValues; 064 } 065 066 /** 067 * {@inheritDoc} 068 */ 069 @Override 070 public Set<String> getContextLabels() { 071 return stream().map(Pair::getKey).collect(Collectors.toSet()); 072 } 073 074 /** 075 * {@inheritDoc} 076 */ 077 @Override 078 public List<Object> getContextValues(final String label) { 079 return stream().filter(pair -> StringUtils.equals(label, pair.getKey())).map(Pair::getValue).collect(Collectors.toList()); 080 } 081 082 /** 083 * {@inheritDoc} 084 */ 085 @Override 086 public Object getFirstContextValue(final String label) { 087 return stream().filter(pair -> StringUtils.equals(label, pair.getKey())).findFirst().map(Pair::getValue).orElse(null); 088 } 089 090 /** 091 * Builds the message containing the contextual information. 092 * 093 * @param baseMessage the base exception message <b>without</b> context information appended 094 * @return the exception message <b>with</b> context information appended, never null 095 */ 096 @Override 097 public String getFormattedExceptionMessage(final String baseMessage) { 098 final StringBuilder buffer = new StringBuilder(256); 099 if (baseMessage != null) { 100 buffer.append(baseMessage); 101 } 102 103 if (!contextValues.isEmpty()) { 104 if (buffer.length() > 0) { 105 buffer.append('\n'); 106 } 107 buffer.append("Exception Context:\n"); 108 109 int i = 0; 110 for (final Pair<String, Object> pair : contextValues) { 111 buffer.append("\t["); 112 buffer.append(++i); 113 buffer.append(':'); 114 buffer.append(pair.getKey()); 115 buffer.append("="); 116 final Object value = pair.getValue(); 117 if (value == null) { 118 buffer.append("null"); 119 } else { 120 String valueStr; 121 try { 122 valueStr = value.toString(); 123 } catch (final Exception e) { 124 valueStr = "Exception thrown on toString(): " + ExceptionUtils.getStackTrace(e); 125 } 126 buffer.append(valueStr); 127 } 128 buffer.append("]\n"); 129 } 130 buffer.append("---------------------------------"); 131 } 132 return buffer.toString(); 133 } 134 135 /** 136 * {@inheritDoc} 137 */ 138 @Override 139 public DefaultExceptionContext setContextValue(final String label, final Object value) { 140 contextValues.removeIf(p -> StringUtils.equals(label, p.getKey())); 141 addContextValue(label, value); 142 return this; 143 } 144 145 private Stream<Pair<String, Object>> stream() { 146 return contextValues.stream(); 147 } 148 149}