Update #0 - First Release

sources/main/java/com/google/common/collect/Platform.java

@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2008 The Guava Authors
+ *
+ * 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.google.common.collect;
+
+import java.lang.reflect.Array;
+import java.util.Collections;
+import java.util.Map;
+import java.util.NavigableMap;
+import java.util.NavigableSet;
+import java.util.Set;
+import java.util.SortedMap;
+import java.util.SortedSet;
+
+import com.google.common.annotations.GwtCompatible;
+import com.google.common.base.Function;
+import com.google.common.base.Predicate;
+import com.google.common.collect.Maps.EntryTransformer;
+
+/**
+ * Methods factored out so that they can be emulated differently in GWT.
+ *
+ * @author Hayward Chan
+ */
+@GwtCompatible(emulated = true)
+final class Platform {
+	/**
+	 * Returns a new array of the given length with the same type as a reference
+	 * array.
+	 *
+	 * @param reference any array of the desired type
+	 * @param length    the length of the new array
+	 */
+	static <T> T[] newArray(T[] reference, int length) {
+		Class<?> type = reference.getClass().getComponentType();
+
+		// the cast is safe because
+		// result.getClass() == reference.getClass().getComponentType()
+		@SuppressWarnings("unchecked")
+		T[] result = (T[]) Array.newInstance(type, length);
+		return result;
+	}
+
+	static <E> Set<E> newSetFromMap(Map<E, Boolean> map) {
+		return Collections.newSetFromMap(map);
+	}
+
+	static <K, V1, V2> SortedMap<K, V2> mapsTransformEntriesSortedMap(SortedMap<K, V1> fromMap,
+			EntryTransformer<? super K, ? super V1, V2> transformer) {
+		return (fromMap instanceof NavigableMap) ? Maps.transformEntries((NavigableMap<K, V1>) fromMap, transformer)
+				: Maps.transformEntriesIgnoreNavigable(fromMap, transformer);
+	}
+
+	static <K, V> SortedMap<K, V> mapsAsMapSortedSet(SortedSet<K> set, Function<? super K, V> function) {
+		return (set instanceof NavigableSet) ? Maps.asMap((NavigableSet<K>) set, function)
+				: Maps.asMapSortedIgnoreNavigable(set, function);
+	}
+
+	static <E> SortedSet<E> setsFilterSortedSet(SortedSet<E> set, Predicate<? super E> predicate) {
+		return (set instanceof NavigableSet) ? Sets.filter((NavigableSet<E>) set, predicate)
+				: Sets.filterSortedIgnoreNavigable(set, predicate);
+	}
+
+	static <K, V> SortedMap<K, V> mapsFilterSortedMap(SortedMap<K, V> map,
+			Predicate<? super Map.Entry<K, V>> predicate) {
+		return (map instanceof NavigableMap) ? Maps.filterEntries((NavigableMap<K, V>) map, predicate)
+				: Maps.filterSortedIgnoreNavigable(map, predicate);
+	}
+
+	private Platform() {
+	}
+}