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/* * Copyright (C) 2008 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.gson; import java.math.BigDecimal; import java.math.BigInteger; import java.util.ArrayList; import java.util.Iterator; import java.util.List; /** * A class representing an array type in Json. An array is a list of {@link JsonElement}s each of * which can be of a different type. This is an ordered list, meaning that the order in which * elements are added is preserved. * * @author Inderjeet Singh * @author Joel Leitch */ public final class JsonArray extends JsonElement implements Iterable<JsonElement> { private final List<JsonElement> elements; /** * Creates an empty JsonArray. */ public JsonArray() { elements = new ArrayList<JsonElement>(); } public JsonArray(int capacity) { elements = new ArrayList<JsonElement>(capacity); } /** * Creates a deep copy of this element and all its children * @since 2.8.2 */ @Override public JsonArray deepCopy() { if (!elements.isEmpty()) { JsonArray result = new JsonArray(elements.size()); for (JsonElement element : elements) { result.add(element.deepCopy()); } return result; } return new JsonArray(); } /** * Adds the specified boolean to self. * * @param bool the boolean that needs to be added to the array. */ public void add(Boolean bool) { elements.add(bool == null ? JsonNull.INSTANCE : new JsonPrimitive(bool)); } /** * Adds the specified character to self. * * @param character the character that needs to be added to the array. */ public void add(Character character) { elements.add(character == null ? JsonNull.INSTANCE : new JsonPrimitive(character)); } /** * Adds the specified number to self. * * @param number the number that needs to be added to the array. */ public void add(Number number) { elements.add(number == null ? JsonNull.INSTANCE : new JsonPrimitive(number)); } /** * Adds the specified string to self. * * @param string the string that needs to be added to the array. */ public void add(String string) { elements.add(string == null ? JsonNull.INSTANCE : new JsonPrimitive(string)); } /** * Adds the specified element to self. * * @param element the element that needs to be added to the array. */ public void add(JsonElement element) { if (element == null) { element = JsonNull.INSTANCE; } elements.add(element); } /** * Adds all the elements of the specified array to self. * * @param array the array whose elements need to be added to the array. */ public void addAll(JsonArray array) { elements.addAll(array.elements); } /** * Replaces the element at the specified position in this array with the specified element. * Element can be null. * @param index index of the element to replace * @param element element to be stored at the specified position * @return the element previously at the specified position * @throws IndexOutOfBoundsException if the specified index is outside the array bounds */ public JsonElement set(int index, JsonElement element) { return elements.set(index, element); } /** * Removes the first occurrence of the specified element from this array, if it is present. * If the array does not contain the element, it is unchanged. * @param element element to be removed from this array, if present * @return true if this array contained the specified element, false otherwise * @since 2.3 */ public boolean remove(JsonElement element) { return elements.remove(element); } /** * Removes the element at the specified position in this array. Shifts any subsequent elements * to the left (subtracts one from their indices). Returns the element that was removed from * the array. * @param index index the index of the element to be removed * @return the element previously at the specified position * @throws IndexOutOfBoundsException if the specified index is outside the array bounds * @since 2.3 */ public JsonElement remove(int index) { return elements.remove(index); } /** * Returns true if this array contains the specified element. * @return true if this array contains the specified element. * @param element whose presence in this array is to be tested * @since 2.3 */ public boolean contains(JsonElement element) { return elements.contains(element); } /** * Returns the number of elements in the array. * * @return the number of elements in the array. */ public int size() { return elements.size(); } /** * Returns an iterator to navigate the elements of the array. Since the array is an ordered list, * the iterator navigates the elements in the order they were inserted. * * @return an iterator to navigate the elements of the array. */ public Iterator<JsonElement> iterator() { return elements.iterator(); } /** * Returns the ith element of the array. * * @param i the index of the element that is being sought. * @return the element present at the ith index. * @throws IndexOutOfBoundsException if i is negative or greater than or equal to the * {@link #size()} of the array. */ public JsonElement get(int i) { return elements.get(i); } /** * convenience method to get this array as a {@link Number} if it contains a single element. * * @return get this element as a number if it is single element array. * @throws ClassCastException if the element in the array is of not a {@link JsonPrimitive} and * is not a valid Number. * @throws IllegalStateException if the array has more than one element. */ @Override public Number getAsNumber() { if (elements.size() == 1) { return elements.get(0).getAsNumber(); } throw new IllegalStateException(); } /** * convenience method to get this array as a {@link String} if it contains a single element. * * @return get this element as a String if it is single element array. * @throws ClassCastException if the element in the array is of not a {@link JsonPrimitive} and * is not a valid String. * @throws IllegalStateException if the array has more than one element. */ @Override public String getAsString() { if (elements.size() == 1) { return elements.get(0).getAsString(); } throw new IllegalStateException(); } /** * convenience method to get this array as a double if it contains a single element. * * @return get this element as a double if it is single element array. * @throws ClassCastException if the element in the array is of not a {@link JsonPrimitive} and * is not a valid double. * @throws IllegalStateException if the array has more than one element. */ @Override public double getAsDouble() { if (elements.size() == 1) { return elements.get(0).getAsDouble(); } throw new IllegalStateException(); } /** * convenience method to get this array as a {@link BigDecimal} if it contains a single element. * * @return get this element as a {@link BigDecimal} if it is single element array. * @throws ClassCastException if the element in the array is of not a {@link JsonPrimitive}. * @throws NumberFormatException if the element at index 0 is not a valid {@link BigDecimal}. * @throws IllegalStateException if the array has more than one element. * @since 1.2 */ @Override public BigDecimal getAsBigDecimal() { if (elements.size() == 1) { return elements.get(0).getAsBigDecimal(); } throw new IllegalStateException(); } /** * convenience method to get this array as a {@link BigInteger} if it contains a single element. * * @return get this element as a {@link BigInteger} if it is single element array. * @throws ClassCastException if the element in the array is of not a {@link JsonPrimitive}. * @throws NumberFormatException if the element at index 0 is not a valid {@link BigInteger}. * @throws IllegalStateException if the array has more than one element. * @since 1.2 */ @Override public BigInteger getAsBigInteger() { if (elements.size() == 1) { return elements.get(0).getAsBigInteger(); } throw new IllegalStateException(); } /** * convenience method to get this array as a float if it contains a single element. * * @return get this element as a float if it is single element array. * @throws ClassCastException if the element in the array is of not a {@link JsonPrimitive} and * is not a valid float. * @throws IllegalStateException if the array has more than one element. */ @Override public float getAsFloat() { if (elements.size() == 1) { return elements.get(0).getAsFloat(); } throw new IllegalStateException(); } /** * convenience method to get this array as a long if it contains a single element. * * @return get this element as a long if it is single element array. * @throws ClassCastException if the element in the array is of not a {@link JsonPrimitive} and * is not a valid long. * @throws IllegalStateException if the array has more than one element. */ @Override public long getAsLong() { if (elements.size() == 1) { return elements.get(0).getAsLong(); } throw new IllegalStateException(); } /** * convenience method to get this array as an integer if it contains a single element. * * @return get this element as an integer if it is single element array. * @throws ClassCastException if the element in the array is of not a {@link JsonPrimitive} and * is not a valid integer. * @throws IllegalStateException if the array has more than one element. */ @Override public int getAsInt() { if (elements.size() == 1) { return elements.get(0).getAsInt(); } throw new IllegalStateException(); } @Override public byte getAsByte() { if (elements.size() == 1) { return elements.get(0).getAsByte(); } throw new IllegalStateException(); } @Override public char getAsCharacter() { if (elements.size() == 1) { return elements.get(0).getAsCharacter(); } throw new IllegalStateException(); } /** * convenience method to get this array as a primitive short if it contains a single element. * * @return get this element as a primitive short if it is single element array. * @throws ClassCastException if the element in the array is of not a {@link JsonPrimitive} and * is not a valid short. * @throws IllegalStateException if the array has more than one element. */ @Override public short getAsShort() { if (elements.size() == 1) { return elements.get(0).getAsShort(); } throw new IllegalStateException(); } /** * convenience method to get this array as a boolean if it contains a single element. * * @return get this element as a boolean if it is single element array. * @throws ClassCastException if the element in the array is of not a {@link JsonPrimitive} and * is not a valid boolean. * @throws IllegalStateException if the array has more than one element. */ @Override public boolean getAsBoolean() { if (elements.size() == 1) { return elements.get(0).getAsBoolean(); } throw new IllegalStateException(); } @Override public boolean equals(Object o) { return (o == this) || (o instanceof JsonArray && ((JsonArray) o).elements.equals(elements)); } @Override public int hashCode() { return elements.hashCode(); } }