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/*******************************************************************************
* Copyright 2011 See AUTHORS file.
*
* 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 com.badlogic.gdx.utils;
import java.util.Arrays;
import java.util.Iterator;
import java.util.NoSuchElementException;
import com.badlogic.gdx.math.MathUtils;
import com.badlogic.gdx.utils.ObjectMap.Entry;
import com.badlogic.gdx.utils.reflect.ArrayReflection;
/** An ordered or unordered map of objects. This implementation uses arrays to store the keys and values, which means
* {@link #getKey(Object, boolean) gets} do a comparison for each key in the map. This is slower than a typical hash map
* implementation, but may be acceptable for small maps and has the benefits that keys and values can be accessed by index, which
* makes iteration fast. Like {@link Array}, if ordered is false, this class avoids a memory copy when removing elements (the last
* element is moved to the removed element's position).
* @author Nathan Sweet */
public class ArrayMap implements Iterable> {
public K[] keys;
public V[] values;
public int size;
public boolean ordered;
private transient Entries entries1, entries2;
private transient Values values1, values2;
private transient Keys keys1, keys2;
/** Creates an ordered map with a capacity of 16. */
public ArrayMap () {
this(true, 16);
}
/** Creates an ordered map with the specified capacity. */
public ArrayMap (int capacity) {
this(true, capacity);
}
/** @param ordered If false, methods that remove elements may change the order of other elements in the arrays, which avoids a
* memory copy.
* @param capacity Any elements added beyond this will cause the backing arrays to be grown. */
public ArrayMap (boolean ordered, int capacity) {
this.ordered = ordered;
keys = (K[])new Object[capacity];
values = (V[])new Object[capacity];
}
/** Creates a new map with {@link #keys} and {@link #values} of the specified type.
* @param ordered If false, methods that remove elements may change the order of other elements in the arrays, which avoids a
* memory copy.
* @param capacity Any elements added beyond this will cause the backing arrays to be grown. */
public ArrayMap (boolean ordered, int capacity, Class keyArrayType, Class valueArrayType) {
this.ordered = ordered;
keys = (K[])ArrayReflection.newInstance(keyArrayType, capacity);
values = (V[])ArrayReflection.newInstance(valueArrayType, capacity);
}
/** Creates an ordered map with {@link #keys} and {@link #values} of the specified type and a capacity of 16. */
public ArrayMap (Class keyArrayType, Class valueArrayType) {
this(false, 16, keyArrayType, valueArrayType);
}
/** Creates a new map containing the elements in the specified map. The new map will have the same type of backing arrays and
* will be ordered if the specified map is ordered. The capacity is set to the number of elements, so any subsequent elements
* added will cause the backing arrays to be grown. */
public ArrayMap (ArrayMap array) {
this(array.ordered, array.size, array.keys.getClass().getComponentType(), array.values.getClass().getComponentType());
size = array.size;
System.arraycopy(array.keys, 0, keys, 0, size);
System.arraycopy(array.values, 0, values, 0, size);
}
public int put (K key, V value) {
int index = indexOfKey(key);
if (index == -1) {
if (size == keys.length) resize(Math.max(8, (int)(size * 1.75f)));
index = size++;
}
keys[index] = key;
values[index] = value;
return index;
}
public int put (K key, V value, int index) {
int existingIndex = indexOfKey(key);
if (existingIndex != -1)
removeIndex(existingIndex);
else if (size == keys.length) //
resize(Math.max(8, (int)(size * 1.75f)));
System.arraycopy(keys, index, keys, index + 1, size - index);
System.arraycopy(values, index, values, index + 1, size - index);
keys[index] = key;
values[index] = value;
size++;
return index;
}
public void putAll (ArrayMap map) {
putAll(map, 0, map.size);
}
public void putAll (ArrayMap map, int offset, int length) {
if (offset + length > map.size)
throw new IllegalArgumentException("offset + length must be <= size: " + offset + " + " + length + " <= " + map.size);
int sizeNeeded = size + length - offset;
if (sizeNeeded >= keys.length) resize(Math.max(8, (int)(sizeNeeded * 1.75f)));
System.arraycopy(map.keys, offset, keys, size, length);
System.arraycopy(map.values, offset, values, size, length);
size += length;
}
/** Returns the value (which may be null) for the specified key, or null if the key is not in the map. Note this does a
* .equals() comparison of each key in reverse order until the specified key is found. */
public @Null V get (K key) {
return get(key, null);
}
/** Returns the value (which may be null) for the specified key, or the default value if the key is not in the map. Note this
* does a .equals() comparison of each key in reverse order until the specified key is found. */
public @Null V get (K key, @Null V defaultValue) {
Object[] keys = this.keys;
int i = size - 1;
if (key == null) {
for (; i >= 0; i--)
if (keys[i] == key) return values[i];
} else {
for (; i >= 0; i--)
if (key.equals(keys[i])) return values[i];
}
return defaultValue;
}
/** Returns the key for the specified value. Note this does a comparison of each value in reverse order until the specified
* value is found.
* @param identity If true, == comparison will be used. If false, .equals() comparison will be used. */
public @Null K getKey (V value, boolean identity) {
Object[] values = this.values;
int i = size - 1;
if (identity || value == null) {
for (; i >= 0; i--)
if (values[i] == value) return keys[i];
} else {
for (; i >= 0; i--)
if (value.equals(values[i])) return keys[i];
}
return null;
}
public K getKeyAt (int index) {
if (index >= size) throw new IndexOutOfBoundsException(String.valueOf(index));
return keys[index];
}
public V getValueAt (int index) {
if (index >= size) throw new IndexOutOfBoundsException(String.valueOf(index));
return values[index];
}
public K firstKey () {
if (size == 0) throw new IllegalStateException("Map is empty.");
return keys[0];
}
public V firstValue () {
if (size == 0) throw new IllegalStateException("Map is empty.");
return values[0];
}
public void setKey (int index, K key) {
if (index >= size) throw new IndexOutOfBoundsException(String.valueOf(index));
keys[index] = key;
}
public void setValue (int index, V value) {
if (index >= size) throw new IndexOutOfBoundsException(String.valueOf(index));
values[index] = value;
}
public void insert (int index, K key, V value) {
if (index > size) throw new IndexOutOfBoundsException(String.valueOf(index));
if (size == keys.length) resize(Math.max(8, (int)(size * 1.75f)));
if (ordered) {
System.arraycopy(keys, index, keys, index + 1, size - index);
System.arraycopy(values, index, values, index + 1, size - index);
} else {
keys[size] = keys[index];
values[size] = values[index];
}
size++;
keys[index] = key;
values[index] = value;
}
public boolean containsKey (K key) {
K[] keys = this.keys;
int i = size - 1;
if (key == null) {
while (i >= 0)
if (keys[i--] == key) return true;
} else {
while (i >= 0)
if (key.equals(keys[i--])) return true;
}
return false;
}
/** @param identity If true, == comparison will be used. If false, .equals() comparison will be used. */
public boolean containsValue (V value, boolean identity) {
V[] values = this.values;
int i = size - 1;
if (identity || value == null) {
while (i >= 0)
if (values[i--] == value) return true;
} else {
while (i >= 0)
if (value.equals(values[i--])) return true;
}
return false;
}
public int indexOfKey (K key) {
Object[] keys = this.keys;
if (key == null) {
for (int i = 0, n = size; i < n; i++)
if (keys[i] == key) return i;
} else {
for (int i = 0, n = size; i < n; i++)
if (key.equals(keys[i])) return i;
}
return -1;
}
public int indexOfValue (V value, boolean identity) {
Object[] values = this.values;
if (identity || value == null) {
for (int i = 0, n = size; i < n; i++)
if (values[i] == value) return i;
} else {
for (int i = 0, n = size; i < n; i++)
if (value.equals(values[i])) return i;
}
return -1;
}
public @Null V removeKey (K key) {
Object[] keys = this.keys;
if (key == null) {
for (int i = 0, n = size; i < n; i++) {
if (keys[i] == key) {
V value = values[i];
removeIndex(i);
return value;
}
}
} else {
for (int i = 0, n = size; i < n; i++) {
if (key.equals(keys[i])) {
V value = values[i];
removeIndex(i);
return value;
}
}
}
return null;
}
public boolean removeValue (V value, boolean identity) {
Object[] values = this.values;
if (identity || value == null) {
for (int i = 0, n = size; i < n; i++) {
if (values[i] == value) {
removeIndex(i);
return true;
}
}
} else {
for (int i = 0, n = size; i < n; i++) {
if (value.equals(values[i])) {
removeIndex(i);
return true;
}
}
}
return false;
}
/** Removes and returns the key/values pair at the specified index. */
public void removeIndex (int index) {
if (index >= size) throw new IndexOutOfBoundsException(String.valueOf(index));
Object[] keys = this.keys;
size--;
if (ordered) {
System.arraycopy(keys, index + 1, keys, index, size - index);
System.arraycopy(values, index + 1, values, index, size - index);
} else {
keys[index] = keys[size];
values[index] = values[size];
}
keys[size] = null;
values[size] = null;
}
/** Returns true if the map has one or more items. */
public boolean notEmpty () {
return size > 0;
}
/** Returns true if the map is empty. */
public boolean isEmpty () {
return size == 0;
}
/** Returns the last key. */
public K peekKey () {
return keys[size - 1];
}
/** Returns the last value. */
public V peekValue () {
return values[size - 1];
}
/** Clears the map and reduces the size of the backing arrays to be the specified capacity if they are larger. */
public void clear (int maximumCapacity) {
if (keys.length <= maximumCapacity) {
clear();
return;
}
size = 0;
resize(maximumCapacity);
}
public void clear () {
Arrays.fill(keys, 0, size, null);
Arrays.fill(values, 0, size, null);
size = 0;
}
/** Reduces the size of the backing arrays to the size of the actual number of entries. This is useful to release memory when
* many items have been removed, or if it is known that more entries will not be added. */
public void shrink () {
if (keys.length == size) return;
resize(size);
}
/** Increases the size of the backing arrays to accommodate the specified number of additional entries. Useful before adding
* many entries to avoid multiple backing array resizes. */
public void ensureCapacity (int additionalCapacity) {
if (additionalCapacity < 0) throw new IllegalArgumentException("additionalCapacity must be >= 0: " + additionalCapacity);
int sizeNeeded = size + additionalCapacity;
if (sizeNeeded > keys.length) resize(Math.max(Math.max(8, sizeNeeded), (int)(size * 1.75f)));
}
protected void resize (int newSize) {
K[] newKeys = (K[])ArrayReflection.newInstance(keys.getClass().getComponentType(), newSize);
System.arraycopy(keys, 0, newKeys, 0, Math.min(size, newKeys.length));
this.keys = newKeys;
V[] newValues = (V[])ArrayReflection.newInstance(values.getClass().getComponentType(), newSize);
System.arraycopy(values, 0, newValues, 0, Math.min(size, newValues.length));
this.values = newValues;
}
public void reverse () {
for (int i = 0, lastIndex = size - 1, n = size / 2; i < n; i++) {
int ii = lastIndex - i;
K tempKey = keys[i];
keys[i] = keys[ii];
keys[ii] = tempKey;
V tempValue = values[i];
values[i] = values[ii];
values[ii] = tempValue;
}
}
public void shuffle () {
for (int i = size - 1; i >= 0; i--) {
int ii = MathUtils.random(i);
K tempKey = keys[i];
keys[i] = keys[ii];
keys[ii] = tempKey;
V tempValue = values[i];
values[i] = values[ii];
values[ii] = tempValue;
}
}
/** Reduces the size of the arrays to the specified size. If the arrays are already smaller than the specified size, no action
* is taken. */
public void truncate (int newSize) {
if (size <= newSize) return;
for (int i = newSize; i < size; i++) {
keys[i] = null;
values[i] = null;
}
size = newSize;
}
public int hashCode () {
K[] keys = this.keys;
V[] values = this.values;
int h = 0;
for (int i = 0, n = size; i < n; i++) {
K key = keys[i];
V value = values[i];
if (key != null) h += key.hashCode() * 31;
if (value != null) h += value.hashCode();
}
return h;
}
public boolean equals (Object obj) {
if (obj == this) return true;
if (!(obj instanceof ArrayMap)) return false;
ArrayMap other = (ArrayMap)obj;
if (other.size != size) return false;
K[] keys = this.keys;
V[] values = this.values;
for (int i = 0, n = size; i < n; i++) {
K key = keys[i];
V value = values[i];
if (value == null) {
if (other.get(key, ObjectMap.dummy) != null) return false;
} else {
if (!value.equals(other.get(key))) return false;
}
}
return true;
}
/** Uses == for comparison of each value. */
public boolean equalsIdentity (Object obj) {
if (obj == this) return true;
if (!(obj instanceof ArrayMap)) return false;
ArrayMap other = (ArrayMap)obj;
if (other.size != size) return false;
K[] keys = this.keys;
V[] values = this.values;
for (int i = 0, n = size; i < n; i++)
if (values[i] != other.get(keys[i], ObjectMap.dummy)) return false;
return true;
}
public String toString () {
if (size == 0) return "{}";
K[] keys = this.keys;
V[] values = this.values;
StringBuilder buffer = new StringBuilder(32);
buffer.append('{');
buffer.append(keys[0]);
buffer.append('=');
buffer.append(values[0]);
for (int i = 1; i < size; i++) {
buffer.append(", ");
buffer.append(keys[i]);
buffer.append('=');
buffer.append(values[i]);
}
buffer.append('}');
return buffer.toString();
}
public Iterator> iterator () {
return entries();
}
/** Returns an iterator for the entries in the map. Remove is supported.
*
* If {@link Collections#allocateIterators} is false, the same iterator instance is returned each time this method is called.
* Use the {@link Entries} constructor for nested or multithreaded iteration.
* @see Collections#allocateIterators */
public Entries entries () {
if (Collections.allocateIterators) return new Entries(this);
if (entries1 == null) {
entries1 = new Entries(this);
entries2 = new Entries(this);
}
if (!entries1.valid) {
entries1.index = 0;
entries1.valid = true;
entries2.valid = false;
return entries1;
}
entries2.index = 0;
entries2.valid = true;
entries1.valid = false;
return entries2;
}
/** Returns an iterator for the values in the map. Remove is supported.
*
* If {@link Collections#allocateIterators} is false, the same iterator instance is returned each time this method is called.
* Use the {@link Entries} constructor for nested or multithreaded iteration.
* @see Collections#allocateIterators */
public Values values () {
if (Collections.allocateIterators) return new Values(this);
if (values1 == null) {
values1 = new Values(this);
values2 = new Values(this);
}
if (!values1.valid) {
values1.index = 0;
values1.valid = true;
values2.valid = false;
return values1;
}
values2.index = 0;
values2.valid = true;
values1.valid = false;
return values2;
}
/** Returns an iterator for the keys in the map. Remove is supported.
*
* If {@link Collections#allocateIterators} is false, the same iterator instance is returned each time this method is called.
* Use the {@link Entries} constructor for nested or multithreaded iteration.
* @see Collections#allocateIterators */
public Keys keys () {
if (Collections.allocateIterators) return new Keys(this);
if (keys1 == null) {
keys1 = new Keys(this);
keys2 = new Keys(this);
}
if (!keys1.valid) {
keys1.index = 0;
keys1.valid = true;
keys2.valid = false;
return keys1;
}
keys2.index = 0;
keys2.valid = true;
keys1.valid = false;
return keys2;
}
static public class Entries implements Iterable>, Iterator> {
private final ArrayMap map;
Entry entry = new Entry();
int index;
boolean valid = true;
public Entries (ArrayMap map) {
this.map = map;
}
public boolean hasNext () {
if (!valid) throw new GdxRuntimeException("#iterator() cannot be used nested.");
return index < map.size;
}
public Iterator> iterator () {
return this;
}
/** Note the same entry instance is returned each time this method is called. */
public Entry next () {
if (index >= map.size) throw new NoSuchElementException(String.valueOf(index));
if (!valid) throw new GdxRuntimeException("#iterator() cannot be used nested.");
entry.key = map.keys[index];
entry.value = map.values[index++];
return entry;
}
public void remove () {
index--;
map.removeIndex(index);
}
public void reset () {
index = 0;
}
}
static public class Values implements Iterable, Iterator {
private final ArrayMap map;
int index;
boolean valid = true;
public Values (ArrayMap map) {
this.map = map;
}
public boolean hasNext () {
if (!valid) throw new GdxRuntimeException("#iterator() cannot be used nested.");
return index < map.size;
}
public Iterator iterator () {
return this;
}
public V next () {
if (index >= map.size) throw new NoSuchElementException(String.valueOf(index));
if (!valid) throw new GdxRuntimeException("#iterator() cannot be used nested.");
return map.values[index++];
}
public void remove () {
index--;
map.removeIndex(index);
}
public void reset () {
index = 0;
}
public Array toArray () {
return new Array(true, map.values, index, map.size - index);
}
public Array toArray (Array array) {
array.addAll(map.values, index, map.size - index);
return array;
}
}
static public class Keys implements Iterable, Iterator {
private final ArrayMap map;
int index;
boolean valid = true;
public Keys (ArrayMap map) {
this.map = map;
}
public boolean hasNext () {
if (!valid) throw new GdxRuntimeException("#iterator() cannot be used nested.");
return index < map.size;
}
public Iterator iterator () {
return this;
}
public K next () {
if (index >= map.size) throw new NoSuchElementException(String.valueOf(index));
if (!valid) throw new GdxRuntimeException("#iterator() cannot be used nested.");
return map.keys[index++];
}
public void remove () {
index--;
map.removeIndex(index);
}
public void reset () {
index = 0;
}
public Array toArray () {
return new Array(true, map.keys, index, map.size - index);
}
public Array toArray (Array array) {
array.addAll(map.keys, index, map.size - index);
return array;
}
}
}