infinispan.com.google.common.collect.Platform Maven / Gradle / Ivy
/*
* 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 com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import java.lang.reflect.Array;
/**
* Methods factored out so that they can be emulated differently in GWT.
*
* @author Hayward Chan
*/
@GwtCompatible(emulated = true)
class Platform {
/**
* Clone the given array using {@link Object#clone()}. It is factored out so
* that it can be emulated in GWT.
*/
static T[] clone(T[] array) {
return array.clone();
}
/**
* Wrapper around {@link System#arraycopy} so that it can be emulated
* correctly in GWT.
*
* It is only intended for the case {@code src} and {@code dest} are
* different. It also doesn't validate the types and indices.
*
*
As of GWT 2.0, The built-in {@link System#arraycopy} doesn't work
* in general case. See
* http://code.google.com/p/google-web-toolkit/issues/detail?id=3621
* for more details.
*/
static void unsafeArrayCopy(
Object[] src, int srcPos, Object[] dest, int destPos, int length) {
System.arraycopy(src, srcPos, dest, destPos, length);
}
/**
* Returns a new array of the given length with the specified component type.
*
* @param type the component type
* @param length the length of the new array
*/
@GwtIncompatible("Array.newInstance(Class, int)")
@SuppressWarnings("unchecked")
static T[] newArray(Class type, int length) {
return (T[]) Array.newInstance(type, length);
}
/**
* 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[] 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;
}
/**
* Configures the given map maker to use weak keys, if possible; does nothing
* otherwise (i.e., in GWT). This is sometimes acceptable, when only
* server-side code could generate enough volume that reclamation becomes
* important.
*/
static MapMaker tryWeakKeys(MapMaker mapMaker) {
return mapMaker.weakKeys();
}
private Platform() {}
}