/*
* Copyright 2015-present Facebook, Inc.
*
* 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.facebook.buck.util;
import com.google.common.base.Function;
import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSortedMap;
import java.util.HashMap;
import java.util.Map;
import javax.annotation.Nullable;
public class MoreMaps {
private MoreMaps() {}
public static <K, V> Map<K, V> putCheckEquals(Map<K, V> map, K key, @Nullable V value) {
V old = map.put(key, value);
if (old != null) {
Preconditions.checkState(old.equals(value));
}
return map;
}
public static <K1, K2, V> ImmutableMap<K2, V> transformKeys(
Map<K1, V> map, Function<? super K1, K2> transformer) {
ImmutableMap.Builder<K2, V> transformedMap = ImmutableMap.builder();
for (Map.Entry<K1, V> ent : map.entrySet()) {
transformedMap.put(
Preconditions.checkNotNull(transformer.apply(ent.getKey())), ent.getValue());
}
return transformedMap.build();
}
public static <K1, K2 extends Comparable<?>, V> ImmutableSortedMap<K2, V> transformKeysAndSort(
Map<K1, V> map, Function<? super K1, K2> transformer) {
ImmutableSortedMap.Builder<K2, V> transformedMap = ImmutableSortedMap.naturalOrder();
for (Map.Entry<K1, V> ent : map.entrySet()) {
transformedMap.put(
Preconditions.checkNotNull(transformer.apply(ent.getKey())), ent.getValue());
}
return transformedMap.build();
}
public static <K, V> ImmutableMap<K, V> merge(Map<K, V> first, Map<K, V> second) {
Map<K, V> mutableMap = new HashMap<>(first);
mutableMap.putAll(second);
return ImmutableMap.copyOf(mutableMap);
}
public static <K, V> ImmutableSortedMap<K, V> mergeSorted(Map<K, V> first, Map<K, V> second) {
Map<K, V> mutableMap = new HashMap<>(first);
mutableMap.putAll(second);
return ImmutableSortedMap.copyOf(mutableMap);
}
}