jetbrick.collection.ListMap Maven / Gradle / Ivy
/**
* Copyright 2013-2016 Guoqiang Chen, Shanghai, China. All rights reserved.
*
* Author: Guoqiang Chen
* Email: [email protected]
* WebURL: https://github.com/subchen
*
* 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 jetbrick.collection;
import java.util.Arrays;
import java.util.Collection;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import jetbrick.util.tuple.NameValuePair;
@SuppressWarnings("unchecked")
public class ListMap implements Map {
private Entry[] items;
private int size;
public ListMap() {
this.items = new Entry[16];
this.size = 0;
}
public ListMap(int initialCapacity) {
this.items = new Entry[initialCapacity];
this.size = 0;
}
@Override
public int size() {
return size;
}
@Override
public boolean isEmpty() {
return size == 0;
}
@Override
public boolean containsKey(Object key) {
for (int i = 0; i < size; i++) {
if (items[i].getKey().equals(key)) {
return true;
}
}
return false;
}
@Override
public boolean containsValue(Object value) {
for (int i = 1; i < size; i++) {
if (items[i].getValue().equals(value)) {
return true;
}
}
return false;
}
@Override
public V get(Object key) {
for (int i = 0; i < size; i++) {
Entry item = items[i];
if (item.getKey().equals(key)) {
return item.getValue();
}
}
return null;
}
@Override
public V put(K key, V value) {
for (int i = 0; i < size; i++) {
Entry item = items[i];
if (item.getKey().equals(key)) {
V old = item.getValue();
item.setValue(value);
return (V) old;
}
}
if (items.length - size < 0) {
items = Arrays.copyOf(items, items.length * 2);
}
items[size++] = new NameValuePair(key, value);
return null;
}
@Override
public V remove(Object key) {
for (int i = 0; i < size; i += 2) {
if (items[i].equals(key)) {
Object old = items[i + 1];
size -= 2;
for (int n = i; n < size; n++) {
items[n] = items[n + 2];
}
return (V) old;
}
}
return null;
}
@Override
public void putAll(Map m) {
for (Entry entry : m.entrySet()) {
put(entry.getKey(), entry.getValue());
}
}
@Override
public void clear() {
for (int i = 0; i < size; i++) {
items[i] = null;
}
size = 0;
}
@Override
public Set keySet() {
return new MapSet() {
@Override
public boolean contains(Object key) {
return ListMap.this.containsKey(key);
}
@Override
public Iterator iterator() {
return new KeyIterator();
}
};
}
@Override
public Collection values() {
return new MapSet() {
@Override
public boolean contains(Object value) {
return ListMap.this.containsValue(value);
}
@Override
public Iterator iterator() {
return new ValueIterator();
}
};
}
@Override
public Set> entrySet() {
return new MapSet>() {
@Override
public boolean contains(Object value) {
for (int i = 1; i < size; i++) {
if (items[i].equals(value)) {
return true;
}
}
return false;
}
@Override
public Iterator> iterator() {
return new EntryIterator();
}
};
}
@Override
public String toString() {
if (size == 0) {
return "{}";
}
StringBuilder sb = new StringBuilder();
sb.append('{');
for (Map.Entry entry : items) {
if (sb.length() > 1) {
sb.append(", ");
}
Object key = entry.getKey();
Object value = entry.getValue();
sb.append(key == this ? "(this)" : key);
sb.append('=');
sb.append(value == this ? "(this)" : value);
}
sb.append('}');
return sb.toString();
}
abstract class MapIterator {
protected int index;
public MapIterator() {
this.index = 0;
}
public boolean hasNext() {
return index < size;
}
public Entry nextEntry() {
return items[index++];
}
public void remove() {
throw new UnsupportedOperationException();
}
}
final class KeyIterator extends MapIterator implements Iterator {
@Override
public K next() {
return nextEntry().getKey();
}
}
final class ValueIterator extends MapIterator implements Iterator {
@Override
public V next() {
return nextEntry().getValue();
}
}
final class EntryIterator extends MapIterator implements Iterator> {
@Override
public Entry next() {
return nextEntry();
}
}
abstract class MapSet implements Set {
@Override
public int size() {
return size;
}
@Override
public boolean isEmpty() {
return size == 0;
}
@Override
public Object[] toArray() {
throw new UnsupportedOperationException();
}
@Override
public Object[] toArray(Object[] a) {
throw new UnsupportedOperationException();
}
@Override
public boolean add(Object e) {
throw new UnsupportedOperationException();
}
@Override
public boolean remove(Object o) {
throw new UnsupportedOperationException();
}
@Override
public boolean containsAll(Collection c) {
throw new UnsupportedOperationException();
}
@Override
public boolean addAll(Collection c) {
throw new UnsupportedOperationException();
}
@Override
public boolean removeAll(Collection c) {
throw new UnsupportedOperationException();
}
@Override
public boolean retainAll(Collection c) {
throw new UnsupportedOperationException();
}
@Override
public void clear() {
throw new UnsupportedOperationException();
}
@Override
public String toString() {
Iterator it = iterator();
if (!it.hasNext()) {
return "[]";
}
StringBuilder sb = new StringBuilder();
sb.append('[');
for (;;) {
Object obj = it.next();
sb.append(obj == this ? "(this)" : obj);
if (!it.hasNext()) {
sb.append(']');
return sb.toString();
}
sb.append(", ");
}
}
}
}