net.hasor.cobble.ref.LinkedCaseInsensitiveMap Maven / Gradle / Ivy
/*
* Copyright 2002-2009 the original author or authors.
*
* Licensed 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 net.hasor.cobble.ref;
import java.util.*;
import java.util.function.BiConsumer;
import java.util.function.BiFunction;
import java.util.function.Function;
/**
* {@link LinkedHashMap} variant that stores String keys in a case-insensitive
* manner, for example for key-based access in a results table.
*
* Preserves the original order as well as the original casing of keys,
* while allowing for contains, get and remove calls with any case of key.
*
*
Does not support null keys.
*
* 2017-09-13 reduction based on SpringFramework, org.springframework.util.LinkedCaseInsensitiveMap
*
* @author 赵永春 ([email protected])
* @author Juergen Hoeller
* @since 3.0
*/
public class LinkedCaseInsensitiveMap extends LinkedHashMap {
private static final long serialVersionUID = -2744548964742290311L;
private final Map caseInsensitiveKeys;
private final Locale locale;
/**
* Create a new LinkedCaseInsensitiveMap for the default Locale.
* @see String#toLowerCase()
*/
public LinkedCaseInsensitiveMap() {
this(Locale.getDefault());
}
/**
* Create a new LinkedCaseInsensitiveMap that stores lower-case keys
* according to the given Locale.
* @param locale the Locale to use for lower-case conversion
* @see String#toLowerCase(Locale)
*/
public LinkedCaseInsensitiveMap(final Locale locale) {
super();
this.caseInsensitiveKeys = new HashMap<>();
this.locale = locale != null ? locale : Locale.getDefault();
}
/**
* Create a new LinkedCaseInsensitiveMap that wraps a {@link LinkedHashMap}
* with the given initial capacity and stores lower-case keys according
* to the default Locale.
* @param initialCapacity the initial capacity
* @see String#toLowerCase()
*/
public LinkedCaseInsensitiveMap(final int initialCapacity) {
this(initialCapacity, null);
}
/**
* Create a new LinkedCaseInsensitiveMap that wraps a {@link LinkedHashMap}
* with the given initial capacity and stores lower-case keys according
* to the given Locale.
* @param initialCapacity the initial capacity
* @param locale the Locale to use for lower-case conversion
* @see String#toLowerCase(Locale)
*/
public LinkedCaseInsensitiveMap(final int initialCapacity, final Locale locale) {
super(initialCapacity);
this.caseInsensitiveKeys = new HashMap<>(initialCapacity);
this.locale = locale != null ? locale : Locale.getDefault();
}
public LinkedCaseInsensitiveMap(Map columnMap) {
this(Locale.getDefault());
if (columnMap != null) {
this.putAll(columnMap);
}
}
@Override
public V put(final String key, final V value) {
this.caseInsensitiveKeys.put(this.convertKey(key), key);
return super.put(key, value);
}
@Override
public void putAll(Map m) {
m.forEach((BiConsumer) this::put);
}
@Override
public V putIfAbsent(String key, V value) {
String newKey = this.convertKey(key);
V v = get(newKey);
if (v == null) {
v = this.put(newKey, value);
}
return v;
}
@Override
public V computeIfAbsent(String key, Function mappingFunction) {
V v;
if ((v = get(key)) == null) {
V newValue;
if ((newValue = mappingFunction.apply(key)) != null) {
put(key, newValue);
return newValue;
}
}
return v;
}
@Override
public V computeIfPresent(String key, BiFunction remappingFunction) {
Objects.requireNonNull(remappingFunction);
V oldValue;
if ((oldValue = get(key)) != null) {
V newValue = remappingFunction.apply(key, oldValue);
if (newValue != null) {
put(key, newValue);
return newValue;
} else {
remove(key);
return null;
}
} else {
return null;
}
}
@Override
public V compute(String key, BiFunction remappingFunction) {
Objects.requireNonNull(remappingFunction);
V oldValue = get(key);
V newValue = remappingFunction.apply(key, oldValue);
if (newValue == null) {
// delete mapping
if (oldValue != null || containsKey(key)) {
// something to remove
remove(key);
return null;
} else {
// nothing to do. Leave things as they were.
return null;
}
} else {
// add or replace old mapping
put(key, newValue);
return newValue;
}
}
@Override
public V merge(String key, V value, BiFunction remappingFunction) {
Objects.requireNonNull(remappingFunction);
Objects.requireNonNull(value);
V oldValue = get(key);
V newValue = (oldValue == null) ? value : remappingFunction.apply(oldValue, value);
if (newValue == null) {
remove(key);
} else {
put(key, newValue);
}
return newValue;
}
@Override
public boolean containsKey(final Object key) {
return key instanceof String && this.caseInsensitiveKeys.containsKey(this.convertKey((String) key));
}
@Override
public V get(final Object key) {
if (key instanceof String) {
return super.get(this.caseInsensitiveKeys.get(this.convertKey((String) key)));
} else {
return null;
}
}
@Override
public V remove(final Object key) {
if (key instanceof String) {
return super.remove(this.caseInsensitiveKeys.remove(this.convertKey((String) key)));
} else {
return null;
}
}
@Override
public void clear() {
this.caseInsensitiveKeys.clear();
super.clear();
}
/**
* Convert the given key to a case-insensitive key.
* The default implementation converts the key
* to lower-case according to this Map's Locale.
* @param key the user-specified key
* @return the key to use for storing
* @see String#toLowerCase(Locale)
*/
protected String convertKey(final String key) {
return key.toLowerCase(this.locale);
}
}