001// *************************************************************************************************************************** 002// * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file * 003// * distributed with this work for additional information regarding copyright ownership. The ASF licenses this file * 004// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance * 005// * with the License. You may obtain a copy of the License at * 006// * * 007// * http://www.apache.org/licenses/LICENSE-2.0 * 008// * * 009// * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an * 010// * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the * 011// * specific language governing permissions and limitations under the License. * 012// *************************************************************************************************************************** 013package org.apache.juneau.internal; 014 015import static org.apache.juneau.internal.ArrayUtils.*; 016import static org.apache.juneau.internal.ThrowableUtils.*; 017 018import java.util.*; 019 020import org.apache.juneau.*; 021 022/** 023 * An instance of a <code>Map</code> where the keys and values are simple <code>String[]</code> and 024 * <code>Object[]</code> arrays. 025 * 026 * <p> 027 * Typically more efficient than <code>HashMaps</code> for small maps (e.g. <10 entries). 028 * 029 * <p> 030 * Does not support adding or removing entries. 031 * 032 * <p> 033 * Setting values overwrites the value on the underlying value array. 034 */ 035public final class SimpleMap extends AbstractMap<String,Object> { 036 037 final String[] keys; 038 final Object[] values; 039 final Map.Entry<String,Object>[] entries; 040 041 /** 042 * Constructor. 043 * 044 * @param keys The map keys. Must not be <jk>null</jk>. 045 * @param values The map values. Must not be <jk>null</jk>. 046 */ 047 public SimpleMap(String[] keys, Object[] values) { 048 assertFieldNotNull(keys, "keys"); 049 assertFieldNotNull(values, "values"); 050 if (keys.length != values.length) 051 illegalArg("keys ''{0}'' and values ''{1}'' array lengths differ", keys.length, values.length); 052 053 this.keys = keys; 054 this.values = values; 055 entries = new SimpleMapEntry[keys.length]; 056 for (int i = 0; i < keys.length; i++) { 057 if (keys[i] == null) 058 illegalArg("Keys array cannot contain a null value."); 059 entries[i] = new SimpleMapEntry(i); 060 } 061 } 062 063 @Override /* Map */ 064 public Set<Map.Entry<String,Object>> entrySet() { 065 return asSet(entries); 066 } 067 068 @Override /* Map */ 069 public Object get(Object key) { 070 for (int i = 0; i < keys.length; i++) 071 if (keys[i].equals(key)) 072 return values[i]; 073 return null; 074 } 075 076 @Override /* Map */ 077 public Set<String> keySet() { 078 return asSet(keys); 079 } 080 081 @Override /* Map */ 082 public Object put(String key, Object value) { 083 for (int i = 0; i < keys.length; i++) { 084 if (keys[i].equals(key)) { 085 Object v = values[i]; 086 values[i] = value; 087 return v; 088 } 089 } 090 throw new FormattedIllegalArgumentException("No key ''{0}'' defined in map", key); 091 } 092 093 final class SimpleMapEntry implements Map.Entry<String,Object> { 094 095 private int index; 096 097 SimpleMapEntry(int index) { 098 this.index = index; 099 } 100 101 @Override /* Map.Entry */ 102 public String getKey() { 103 return keys[index]; 104 } 105 106 @Override /* Map.Entry */ 107 public Object getValue() { 108 return values[index]; 109 } 110 111 @Override /* Map.Entry */ 112 public Object setValue(Object val) { 113 Object v = values[index]; 114 values[index] = val; 115 return v; 116 } 117 } 118}