com.google.appengine.repackaged.com.google.gson.JsonArray Maven / Gradle / Ivy
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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 com.google.gson.internal.NonNullElementWrapperList;
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. This class does not support {@code null} values. If {@code null}
* is provided as element argument to any of the methods, it is converted to a {@link JsonNull}.
*
* {@code JsonArray} only implements the {@link Iterable} interface but not the {@link List}
* interface. A {@code List} view of it can be obtained with {@link #asList()}.
*
* @author Inderjeet Singh
* @author Joel Leitch
*/
public final class JsonArray extends JsonElement implements Iterable {
private final ArrayList elements;
/**
* Creates an empty JsonArray.
*/
@SuppressWarnings("deprecation") // superclass constructor
public JsonArray() {
elements = new ArrayList<>();
}
/**
* Creates an empty JsonArray with the desired initial capacity.
*
* @param capacity initial capacity.
* @throws IllegalArgumentException if the {@code capacity} is
* negative
* @since 2.8.1
*/
@SuppressWarnings("deprecation") // superclass constructor
public JsonArray(int capacity) {
elements = new ArrayList<>(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.
* @since 2.4
*/
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.
* @since 2.4
*/
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.
* @since 2.4
*/
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.
* @since 2.4
*/
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.
*
* @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 == null ? JsonNull.INSTANCE : 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 true if the array is empty.
*
* @return true if the array is empty.
* @since 2.8.7
*/
public boolean isEmpty() {
return elements.isEmpty();
}
/**
* 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.
*/
@Override
public Iterator iterator() {
return elements.iterator();
}
/**
* Returns the i-th element of the array.
*
* @param i the index of the element that is being sought.
* @return the element present at the i-th 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);
}
private JsonElement getAsSingleElement() {
int size = elements.size();
if (size == 1) {
return elements.get(0);
}
throw new IllegalStateException("Array must have size 1, but has size " + size);
}
/**
* Convenience method to get this array as a {@link Number} if it contains a single element.
* This method calls {@link JsonElement#getAsNumber()} on the element, therefore any
* of the exceptions declared by that method can occur.
*
* @return this element as a number if it is single element array.
* @throws IllegalStateException if the array is empty or has more than one element.
*/
@Override
public Number getAsNumber() {
return getAsSingleElement().getAsNumber();
}
/**
* Convenience method to get this array as a {@link String} if it contains a single element.
* This method calls {@link JsonElement#getAsString()} on the element, therefore any
* of the exceptions declared by that method can occur.
*
* @return this element as a String if it is single element array.
* @throws IllegalStateException if the array is empty or has more than one element.
*/
@Override
public String getAsString() {
return getAsSingleElement().getAsString();
}
/**
* Convenience method to get this array as a double if it contains a single element.
* This method calls {@link JsonElement#getAsDouble()} on the element, therefore any
* of the exceptions declared by that method can occur.
*
* @return this element as a double if it is single element array.
* @throws IllegalStateException if the array is empty or has more than one element.
*/
@Override
public double getAsDouble() {
return getAsSingleElement().getAsDouble();
}
/**
* Convenience method to get this array as a {@link BigDecimal} if it contains a single element.
* This method calls {@link JsonElement#getAsBigDecimal()} on the element, therefore any
* of the exceptions declared by that method can occur.
*
* @return this element as a {@link BigDecimal} if it is single element array.
* @throws IllegalStateException if the array is empty or has more than one element.
* @since 1.2
*/
@Override
public BigDecimal getAsBigDecimal() {
return getAsSingleElement().getAsBigDecimal();
}
/**
* Convenience method to get this array as a {@link BigInteger} if it contains a single element.
* This method calls {@link JsonElement#getAsBigInteger()} on the element, therefore any
* of the exceptions declared by that method can occur.
*
* @return this element as a {@link BigInteger} if it is single element array.
* @throws IllegalStateException if the array is empty or has more than one element.
* @since 1.2
*/
@Override
public BigInteger getAsBigInteger() {
return getAsSingleElement().getAsBigInteger();
}
/**
* Convenience method to get this array as a float if it contains a single element.
* This method calls {@link JsonElement#getAsFloat()} on the element, therefore any
* of the exceptions declared by that method can occur.
*
* @return this element as a float if it is single element array.
* @throws IllegalStateException if the array is empty or has more than one element.
*/
@Override
public float getAsFloat() {
return getAsSingleElement().getAsFloat();
}
/**
* Convenience method to get this array as a long if it contains a single element.
* This method calls {@link JsonElement#getAsLong()} on the element, therefore any
* of the exceptions declared by that method can occur.
*
* @return this element as a long if it is single element array.
* @throws IllegalStateException if the array is empty or has more than one element.
*/
@Override
public long getAsLong() {
return getAsSingleElement().getAsLong();
}
/**
* Convenience method to get this array as an integer if it contains a single element.
* This method calls {@link JsonElement#getAsInt()} on the element, therefore any
* of the exceptions declared by that method can occur.
*
* @return this element as an integer if it is single element array.
* @throws IllegalStateException if the array is empty or has more than one element.
*/
@Override
public int getAsInt() {
return getAsSingleElement().getAsInt();
}
/**
* Convenience method to get this array as a primitive byte if it contains a single element.
* This method calls {@link JsonElement#getAsByte()} on the element, therefore any
* of the exceptions declared by that method can occur.
*
* @return this element as a primitive byte if it is single element array.
* @throws IllegalStateException if the array is empty or has more than one element.
*/
@Override
public byte getAsByte() {
return getAsSingleElement().getAsByte();
}
/**
* Convenience method to get this array as a character if it contains a single element.
* This method calls {@link JsonElement#getAsCharacter()} on the element, therefore any
* of the exceptions declared by that method can occur.
*
* @return this element as a primitive short if it is single element array.
* @throws IllegalStateException if the array is empty or has more than one element.
* @deprecated This method is misleading, as it does not get this element as a char but rather as
* a string's first character.
*/
@Deprecated
@Override
public char getAsCharacter() {
return getAsSingleElement().getAsCharacter();
}
/**
* Convenience method to get this array as a primitive short if it contains a single element.
* This method calls {@link JsonElement#getAsShort()} on the element, therefore any
* of the exceptions declared by that method can occur.
*
* @return this element as a primitive short if it is single element array.
* @throws IllegalStateException if the array is empty or has more than one element.
*/
@Override
public short getAsShort() {
return getAsSingleElement().getAsShort();
}
/**
* Convenience method to get this array as a boolean if it contains a single element.
* This method calls {@link JsonElement#getAsBoolean()} on the element, therefore any
* of the exceptions declared by that method can occur.
*
* @return this element as a boolean if it is single element array.
* @throws IllegalStateException if the array is empty or has more than one element.
*/
@Override
public boolean getAsBoolean() {
return getAsSingleElement().getAsBoolean();
}
/**
* Returns a mutable {@link List} view of this {@code JsonArray}. Changes to the {@code List}
* are visible in this {@code JsonArray} and the other way around.
*
* The {@code List} does not permit {@code null} elements. Unlike {@code JsonArray}'s
* {@code null} handling, a {@link NullPointerException} is thrown when trying to add {@code null}.
* Use {@link JsonNull} for JSON null values.
*
* @return mutable {@code List} view
* @since 2.10
*/
public List asList() {
return new NonNullElementWrapperList<>(elements);
}
/**
* Returns whether the other object is equal to this. This method only considers
* the other object to be equal if it is an instance of {@code JsonArray} and has
* equal elements in the same order.
*/
@Override
public boolean equals(Object o) {
return (o == this) || (o instanceof JsonArray && ((JsonArray) o).elements.equals(elements));
}
/**
* Returns the hash code of this array. This method calculates the hash code based
* on the elements of this array.
*/
@Override
public int hashCode() {
return elements.hashCode();
}
}