Map List
/*
* Copyright (c) 2006-2008 Chris Smith, Shane Mc Cormack, Gregory Holmes
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
//package com.dmdirc.util;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
/**
* Wraps a Map<S, List<T>> with various convenience methods for
* accessing the data. Implements a Map-like interface for easier transition.
*
* @param <S> the type of keys maintained by this map
* @param <T> the type of mapped values
* @author chris
*/
public class MapList<S,T> {
/** Our internal map. */
protected final Map<S, List<T>> map;
/**
* Creates a new, empty MapList.
*/
public MapList() {
map = new HashMap<S, List<T>>();
}
/**
* Creates a new MapList with the values from the specified list.
*
* @param list The MapList whose values should be used
*/
public MapList(final MapList<S,T> list) {
map = list.getMap();
}
/**
* Determines if this MapList is empty. An empty MapList is one that either
* contains no keys, or contains only keys which have no associated values.
*
* @return True if this MapList is empty, false otherwise
*/
public boolean isEmpty() {
for (List<T> list : map.values()) {
if (!list.isEmpty()) {
return false;
}
}
return true;
}
/**
* Determines if this MapList contains the specified key.
*
* @param key The key to look for
* @return True if this MapList contains the specified key, false otherwise
*/
public boolean containsKey(final S key) {
return map.containsKey(key);
}
/**
* Determines if this MapList contains the specified value as a child of
* the specified key.
*
* @param key The key to search under
* @param value The value to look for
* @return True if this MapList contains the specified key/value pair,
* false otherwise
*/
public boolean containsValue(final S key, final T value) {
return map.containsKey(key) && map.get(key).contains(value);
}
/**
* Retrieves the list of values associated with the specified key.
*
* @param key The key whose values are being retrieved
* @return The values belonging to the specified key
*/
public List<T> get(final S key) {
return map.get(key);
}
/**
* Retrieves the value at the specified offset of the specified key.
*
* @param key The key whose values are being retrieved
* @param index The index of the value to retrieve
* @return The specified value of the key
*/
public T get(final S key, final int index) {
return map.get(key).get(index);
}
/**
* Retrieves the list of values associated with the specified key, creating
* the key if neccessary.
*
* @param key The key to retrieve
* @return A list of the specified key's values
*/
public List<T> safeGet(final S key) {
if (!map.containsKey(key)) {
map.put(key, new ArrayList<T>());
}
return map.get(key);
}
/**
* Adds the specified key to the MapList.
*
* @param key The key to be added
*/
public void add(final S key) {
safeGet(key);
}
/**
* Adds the specified value as a child of the specified key. If the key
* didn't previous exist, it is created.
*
* @param key The key to which the value is being added
* @param value The value to be added
*/
public void add(final S key, final T value) {
safeGet(key).add(value);
}
/**
* Adds the specified set of values to the specified key. If the key
* didn't previous exist, it is created.
*
* @param key The key to which the value is being added
* @param values The values to be added
*/
public void add(final S key, final Collection<T> values) {
safeGet(key).addAll(values);
}
/**
* Removes the specified key and all of its values.
*
* @param key The key to remove
*/
public void remove(final S key) {
map.remove(key);
}
/**
* Removes the specified value from all keys.
*
* @param value The value to remove
*/
public void removeFromAll(final T value) {
for (List<T> list : map.values()) {
list.remove(value);
}
}
/**
* Removes the specified value from the specified key.
*
* @param key The key whose value is being removed
* @param value The value to be removed
*/
public void remove(final S key, final T value) {
if (map.containsKey(key)) {
map.get(key).remove(value);
}
}
/**
* Entirely clears this MapList.
*/
public void clear() {
map.clear();
}
/**
* Clears all values of the specified key.
*
* @param key The key to be cleared
*/
public void clear(final S key) {
safeGet(key).clear();
}
/**
* Returns the set of all keys belonging to this MapList.
*
* @return This MapList's keyset
*/
public Set<S> keySet() {
return map.keySet();
}
/**
* Returns a collection of all values belonging to the specified key.
*
* @param key The key whose values are being sought
* @return A collection of values belonging to the key
*/
public Collection<T> values(final S key) {
return map.get(key);
}
/**
* Retrieves the entry set for this MapList.
*
* @return This MapList's entry set
*/
public Set<Map.Entry<S, List<T>>> entrySet() {
return map.entrySet();
}
/**
* Retrieves the map behind this maplist.
*
* @return This MapList's map.
*/
public Map<S, List<T>> getMap() {
return new HashMap<S, List<T>>(map);
}
}
/*
package com.dmdirc.util;
import java.util.ArrayList;
import java.util.List;
import org.junit.Test;
import static org.junit.Assert.*;
public class MapListTest extends junit.framework.TestCase {
@Test
public void testIsEmpty() {
final MapList<String, String> test = new MapList<String, String>();
assertTrue(test.isEmpty());
test.add("a", "b");
assertFalse(test.isEmpty());
test.removeFromAll("b");
assertTrue(test.isEmpty());
}
@Test
public void testAddCollection() {
final MapList<String, String> test = new MapList<String, String>();
final List<String> testList = new ArrayList<String>();
testList.add("d");
testList.add("e");
test.add("key", testList);
assertTrue(test.containsKey("key"));
assertTrue(test.containsValue("key", "d"));
assertTrue(test.containsValue("key", "e"));
}
@Test
public void testClear() {
final MapList<String, String> test = new MapList<String, String>();
test.add("a", "b");
test.add("d", "e");
test.clear();
assertTrue(test.isEmpty());
}
@Test
public void testClearKey() {
final MapList<String, String> test = new MapList<String, String>();
test.add("a", "b");
test.add("d", "e");
test.clear("a");
assertTrue(test.values("a").isEmpty());
assertFalse(test.isEmpty());
}
@Test
public void testRemove() {
final MapList<String, String> test = new MapList<String, String>();
test.add("a", "b");
test.add("d", "e");
test.remove("z", "b");
assertEquals(2, test.keySet().size());
assertEquals(1, test.values("a").size());
assertEquals(1, test.values("d").size());
test.remove("a", "b");
assertEquals(2, test.keySet().size());
assertEquals(0, test.values("a").size());
assertEquals(1, test.values("d").size());
}
@Test
public void testKeySet() {
final MapList<String, String> test = new MapList<String, String>();
test.add("a", "b");
test.add("d", "e");
assertEquals(2, test.keySet().size());
assertTrue(test.keySet().contains("a"));
assertTrue(test.keySet().contains("d"));
}
@Test
public void testContainsKey() {
final MapList<String, String> test = new MapList<String, String>();
test.add("a", "b");
assertTrue(test.containsKey("a"));
}
@Test
public void testContainsValue() {
final MapList<String, String> test = new MapList<String, String>();
test.add("a", "b");
assertTrue(test.containsValue("a", "b"));
}
@Test
public void testGet() {
final MapList<String, String> test = new MapList<String, String>();
test.add("a", "b");
assertTrue(test.get("a").size() == 1);
assertTrue(test.get("a").get(0).equals("b"));
assertTrue(test.get("a", 0).equals("b"));
}
}
*/
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