/*
* Copyright 2012 Google 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.google.gwt.core.client;
/**
* Utility class for manipulating JS arrays. These methods are not on other
* JavaScriptObject subclasses, such as JsArray, because adding new methods might
* break existing subtypes.
*/
public class JsArrayUtils {
/**
* Take a Java array, and produce a JS array that is only used for reading. As
* this is actually a reference to the original array in prod mode, the source
* must not be modified while this copy is in use or you will get different
* behavior between DevMode and prod mode.
*
* @param array source array
* @return JS array, which may be a copy or an alias of the input array
*/
public static JsArrayInteger readOnlyJsArray(byte[] array) {
if (GWT.isScript()) {
return arrayAsJsArrayForProdMode(array).cast();
}
JsArrayInteger dest = JsArrayInteger.createArray().cast();
for (int i = 0; i < array.length; ++i) {
dest.push(array[i]);
}
return dest;
}
/**
* Take a Java array, and produce a JS array that is only used for reading. As
* this is actually a reference to the original array in prod mode, the source
* must not be modified while this copy is in use or you will get different
* behavior between DevMode and prod mode.
*
* @param array source array
* @return JS array, which may be a copy or an alias of the input array
*/
public static JsArrayNumber readOnlyJsArray(double[] array) {
if (GWT.isScript()) {
return arrayAsJsArrayForProdMode(array).cast();
}
JsArrayNumber dest = JsArrayNumber.createArray().cast();
for (int i = 0; i < array.length; ++i) {
dest.push(array[i]);
}
return dest;
}
/**
* Take a Java array, and produce a JS array that is only used for reading. As
* this is actually a reference to the original array in prod mode, the source
* must not be modified while this copy is in use or you will get different
* behavior between DevMode and prod mode.
*
* @param array source array
* @return JS array, which may be a copy or an alias of the input array
*/
public static JsArrayNumber readOnlyJsArray(float[] array) {
if (GWT.isScript()) {
return arrayAsJsArrayForProdMode(array).cast();
}
JsArrayNumber dest = JsArrayNumber.createArray().cast();
for (int i = 0; i < array.length; ++i) {
dest.push(array[i]);
}
return dest;
}
/**
* Take a Java array, and produce a JS array that is only used for reading. As
* this is actually a reference to the original array in prod mode, the source
* must not be modified while this copy is in use or you will get different
* behavior between DevMode and prod mode.
*
* @param array source array
* @return JS array, which may be a copy or an alias of the input array
*/
public static JsArrayInteger readOnlyJsArray(int[] array) {
if (GWT.isScript()) {
return arrayAsJsArrayForProdMode(array).cast();
}
JsArrayInteger dest = JsArrayInteger.createArray().cast();
for (int i = 0; i < array.length; ++i) {
dest.push(array[i]);
}
return dest;
}
/**
* Take a Java array, and produce a JS array that is only used for reading. As
* this is actually a reference to the original array in prod mode, the source
* must not be modified while this copy is in use or you will get different
* behavior between DevMode and prod mode.
* <p>
* <b>NOTE: long values are not supported in JS, so long emulation is slow
* and this method assumes that all the values can be safely stored in a
* double.</b>
*
* @param array source array - its values are assumed to be in the valid range
* for doubles -- if the values exceed 2^53, low-order bits will be lost
* @return JS array, which may be a copy or an alias of the input array
*/
public static JsArrayNumber readOnlyJsArray(long[] array) {
if (GWT.isScript()) {
return arrayAsJsArrayForProdMode(array).cast();
}
JsArrayNumber dest = JsArrayNumber.createArray().cast();
for (int i = 0; i < array.length; ++i) {
dest.push(array[i]);
}
return dest;
}
/**
* Take a Java array, and produce a JS array that is only used for reading. As
* this is actually a reference to the original array in prod mode, the source
* must not be modified while this copy is in use or you will get different
* behavior between DevMode and prod mode.
*
* @param array source array
* @return JS array, which may be a copy or an alias of the input array
*/
public static JsArrayInteger readOnlyJsArray(short[] array) {
if (GWT.isScript()) {
return arrayAsJsArrayForProdMode(array).cast();
}
JsArrayInteger dest = JsArrayInteger.createArray().cast();
for (int i = 0; i < array.length; ++i) {
dest.push(array[i]);
}
return dest;
}
/**
* Take a Java array, and produce a JS array that is only used for reading. As
* this is actually a reference to the original array in prod mode, the source
* must not be modified while this copy is in use or you will get different
* behavior between DevMode and prod mode.
*
* @param array source array
* @return JS array, which may be a copy or an alias of the input array
*/
public static <T extends JavaScriptObject> JsArray<T> readOnlyJsArray(T[] array) {
if (GWT.isScript()) {
return arrayAsJsArrayForProdMode(array).cast();
}
JsArray<T> dest = JavaScriptObject.createArray().cast();
for (int i = 0; i < array.length; ++i) {
dest.push(array[i]);
}
return dest;
}
/**
* In production mode, Java arrays really are JS arrays, so just return it.
*
* @param array must be a Java array of some type
* @return a JavaScriptObject, which should be used as the appropriate type of
* JS array depending on the input array type
*/
private static native JavaScriptObject arrayAsJsArrayForProdMode(Object array) /*-{
return array;
}-*/;
private JsArrayUtils() {
}
}