Java tutorial
/* * Copyright 2014 Grow Bit * * 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 org.turbogwt.core.collections; import com.google.gwt.core.client.GWT; import com.google.gwt.core.client.JavaScriptObject; /** * A more featured extension of {@link com.google.gwt.core.client.JsArray}. * * @param <T> Type of list values * * @author Danilo Reinert */ public class JsArray<T> extends JavaScriptObject { protected JsArray() { } public static <T> JsArray<T> fromArray(T... values) { if (GWT.isScript()) { return reinterpretCast(values); } else { JsArray<T> ret = create(); for (int i = 0, l = values.length; i < l; i++) { ret.set(i, values[i]); } return ret; } } @SuppressWarnings("unchecked") public static <T> JsArray<T> cast(JavaScriptObject jso) { return (JsArray<T>) jso; } @SuppressWarnings("unchecked") public static <T> JsArray<T> create() { return (JsArray<T>) JavaScriptObject.createArray(); } /** * Gets the object at a given index. * * @param index the index to be retrieved * @return the object at the given index, or <code>null</code> if none exists */ public final native T get(int index) /*-{ return this[index]; }-*/; /** * Convert each element of the array to a String and join them with a comma * separator. The value returned from this method may vary between browsers * based on how JavaScript values are converted into strings. * * @return the string representation of joined array */ public final String join() { // As per JS spec return join(","); } /** * Convert each element of the array to a String and join them with a comma * separator. The value returned from this method may vary between browsers * based on how JavaScript values are converted into strings. * * @param separator the string to place between elments of the array * @return the string representation of joined array */ public final native String join(String separator) /*-{ return this.join(separator); }-*/; /** * Gets the length of the array. * * @return the array length */ public final native int length() /*-{ return this.length; }-*/; /** * Pushes the given value onto the end of the array. * * @param value the element to push into the array */ public final native void push(T value) /*-{ this[this.length] = value; }-*/; /** * Sets the object value at a given index. * * If the index is out of bounds, the value will still be set. The array's * length will be updated to encompass the bounds implied by the added object. * * @param index the index to be set * @param value the object to be stored */ public final native void set(int index, T value) /*-{ this[index] = value; }-*/; /** * Reset the length of the array. * * @param newLength the new length of the array */ public final native void setLength(int newLength) /*-{ this.length = newLength; }-*/; /** * Shifts the first value off the array. * * @return the shifted value */ public final native T shift() /*-{ return this.shift(); }-*/; /** * Shifts a value onto the beginning of the array. * * @param value the value to the stored */ public final native void unshift(T value) /*-{ this.unshift(value); }-*/; public final native void splice(int index, T element) /*-{ this.splice(index, 0, element); }-*/; public final native JsArray<T> splice(int index) /*-{ return this.splice(index, 1); }-*/; public final native JsArray<T> splice(int index, int quantity) /*-{ return this.splice(index, quantity); }-*/; public final JsArray<T> splice(int index, int quantity, T... elements) { if (elements.length == 0) { return splice(index, quantity); } if (elements.length > 1) { // TODO: Check if the JsArray is being considered as one element. final JsArray<T> elements1 = JsArray.fromArray(elements); return splice(index, quantity, elements1); } return splice(index, quantity, elements[0]); } public final native JsArray<T> splice(int index, int quantity, T element) /*-{ return this.splice(index, quantity, element); }-*/; // TODO: Check if the JsArray is being considered as one element. public final native JsArray<T> splice(int index, int quantity, JsArray<T> elements) /*-{ return this.splice(index, quantity, elements); }-*/; public final native int indexOf(Object search) /*-{ return this.indexOf(search); }-*/; public final native int lastIndexOf(Object search) /*-{ return this.lastIndexOf(search); }-*/; public final native JsArray<T> slice(int begin) /*-{ return this.slice(begin); }-*/; public final native JsArray<T> slice(int begin, int end) /*-{ return this.slice(begin, end); }-*/; public final native JsArray concat(JsArray<T> a) /*-{ return this.concat(a); }-*/; /** * Appends an array to current one. * * @param a Array to append. */ public final native void pushApply(JsArray<T> a) /*-{ this.push.apply(this, a); }-*/; public final native T pop() /*-{ return this.pop() }-*/; @SuppressWarnings("unchecked") public final Object[] toArray() { if (GWT.isScript()) { return reinterpretCast(slice(0)); } else { int length = length(); T nonNull = null; for (int i = 0; i < length; i++) { nonNull = get(i); if (nonNull != null) break; } T[] ret; if (nonNull instanceof JavaScriptObject) { ret = (T[]) new JavaScriptObject[length]; } else { ret = (T[]) new Object[length]; } for (int i = 0; i < length; i++) { ret[i] = get(i); } return ret; } } private static native <T> T[] reinterpretCast(JsArray<T> value) /*-{ return value; }-*/; private static native <T> JsArray<T> reinterpretCast(T[] value) /*-{ return value; }-*/; }