/*******************************************************************************
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.ofbiz.base.util;
import java.util.Collection;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.Stack;
public final class UtilGenerics {
public static final String module = UtilMisc.class.getName();
private UtilGenerics() {}
@SuppressWarnings("unchecked")
public static <V> V cast(Object object) {
return (V) object;
}
private static <C extends Collection<?>> C checkCollectionCast(Object object, Class<C> clz) {
return clz.cast(object);
}
public static <C extends Collection<?>> void checkCollectionContainment(Object object, Class<C> clz, Class<?> type) {
if (object != null) {
if (!(clz.isInstance(object))) throw new ClassCastException("Not a " + clz.getName());
int i = 0;
for (Object value: (Collection<?>) object) {
if (value != null && !type.isInstance(value)) {
throw new IllegalArgumentException("Value(" + i + "), with value(" + value + ") is not a " + type.getName());
}
i++;
}
}
}
@SuppressWarnings("unchecked")
public static <T> Collection<T> checkCollection(Object object) {
return (Collection<T>) checkCollectionCast(object, Collection.class);
}
public static <T> Collection<T> checkCollection(Object object, Class<T> type) {
checkCollectionContainment(object, Collection.class, type);
return checkCollection(object);
}
@SuppressWarnings("unchecked")
public static <T> List<T> checkList(Object object) {
return (List<T>) checkCollectionCast(object, List.class);
}
public static <T> List<T> checkList(Object object, Class<T> type) {
checkCollectionContainment(object, List.class, type);
return checkList(object);
}
@SuppressWarnings("unchecked")
public static <K, V> Map<K, V> checkMap(Object object) {
if (object != null && !(object instanceof Map)) throw new ClassCastException("Not a map");
return (Map<K, V>) object;
}
public static <K, V> Map<K, V> checkMap(Object object, Class<K> keyType, Class<V> valueType) {
if (object != null) {
if (!(object instanceof Map<?, ?>)) throw new ClassCastException("Not a map");
Map<?, ?> map = (Map<?,?>) object;
int i = 0;
for (Map.Entry<?, ?> entry: map.entrySet()) {
if (entry.getKey() != null && !keyType.isInstance(entry.getKey())) {
throw new IllegalArgumentException("Key(" + i + "), with value(" + entry.getKey() + ") is not a " + keyType);
}
if (entry.getValue() != null && !valueType.isInstance(entry.getValue())) {
throw new IllegalArgumentException("Value(" + i + "), with value(" + entry.getValue() + ") is not a " + valueType);
}
i++;
}
}
return checkMap(object);
}
@SuppressWarnings("unchecked")
public static <T> Stack<T> checkStack(Object object) {
return (Stack<T>) checkCollectionCast(object, Stack.class);
}
public static <T> Stack<T> checkStack(Object object, Class<T> type) {
checkCollectionContainment(object, Stack.class, type);
return checkStack(object);
}
@SuppressWarnings("unchecked")
public static <T> Set<T> checkSet(Object object) {
return (Set<T>) checkCollectionCast(object, Set.class);
}
public static <T> Set<T> checkSet(Object object, Class<T> type) {
checkCollectionContainment(object, Set.class, type);
return checkSet(object);
}
/** Returns the Object argument as a parameterized List if the Object argument
* is an instance of List. Otherwise returns null.
*/
@SuppressWarnings("unchecked")
public static <T> List<T> toList(Object object) {
if (object != null && !(object instanceof List)) return null;
return (List<T>) object;
}
/** Returns the Object argument as a parameterized Map if the Object argument
* is an instance of Map. Otherwise returns null.
*/
@SuppressWarnings("unchecked")
public static <K, V> Map<K, V> toMap(Object object) {
if (object != null && !(object instanceof Map)) return null;
return (Map<K, V>) object;
}
public static <K, V> Map<K, V> toMap(Class<K> keyType, Class<V> valueType, Object... data) {
if (data == null) {
return null;
}
if (data.length % 2 == 1) {
throw new IllegalArgumentException("You must pass an even sized array to the toMap method");
}
Map<K, V> map = new LinkedHashMap<K, V>();
for (int i = 0; i < data.length;) {
Object key = data[i];
if (key != null && !(keyType.isInstance(key))) throw new IllegalArgumentException("Key(" + i + ") is not a " + keyType.getName() + ", was(" + key.getClass().getName() + ")");
i++;
Object value = data[i];
if (value != null && !(valueType.isInstance(value))) throw new IllegalArgumentException("Value(" + i + ") is not a " + keyType.getName() + ", was(" + key.getClass().getName() + ")");
i++;
map.put(keyType.cast(key), valueType.cast(value));
}
return map;
}
@SuppressWarnings("hiding")
public static <K, Object> Map<K, Object> toMap(Class<K> keyType, Object... data) {
if (data == null) {
return null;
}
if (data.length % 2 == 1) {
throw new IllegalArgumentException("You must pass an even sized array to the toMap method");
}
Map<K, Object> map = new LinkedHashMap<K, Object>();
for (int i = 0; i < data.length;) {
Object key = data[i];
if (key != null && !(keyType.isInstance(key))) throw new IllegalArgumentException("Key(" + i + ") is not a " + keyType.getName() + ", was(" + key.getClass().getName() + ")");
i++;
Object value = data[i];
map.put(keyType.cast(key), value);
}
return map;
}
}