/*******************************************************************************
* Copyright (c) 2013, 2015 EclipseSource.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
******************************************************************************/
package org.jmxtrans.agent.util.json;
import java.io.IOException;
import java.io.Reader;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
/**
* Represents a JSON array, an ordered collection of JSON values.
* <p>
* Elements can be added using the <code>add(...)</code> methods which accept instances of
* {@link org.jmxtrans.agent.util.json.JsonValue}, strings, primitive numbers, and boolean values. To replace an element of an
* array, use the <code>set(int, ...)</code> methods.
* </p>
* <p>
* Elements can be accessed by their index using {@link #get(int)}. This class also supports
* iterating over the elements in document order using an {@link #iterator()} or an enhanced for
* loop:
* </p>
* <pre>
* for (JsonValue value : jsonArray) {
* ...
* }
* </pre>
* <p>
* An equivalent {@link List} can be obtained from the method {@link #values()}.
* </p>
* <p>
* Note that this class is <strong>not thread-safe</strong>. If multiple threads access a
* <code>JsonArray</code> instance concurrently, while at least one of these threads modifies the
* contents of this array, access to the instance must be synchronized externally. Failure to do so
* may lead to an inconsistent state.
* </p>
* <p>
* This class is <strong>not supposed to be extended</strong> by clients.
* </p>
*/
@SuppressWarnings("serial") // use default serial UID
public class JsonArray extends org.jmxtrans.agent.util.json.JsonValue implements Iterable<org.jmxtrans.agent.util.json.JsonValue> {
private final List<org.jmxtrans.agent.util.json.JsonValue> values;
/**
* Creates a new empty JsonArray.
*/
public JsonArray() {
values = new ArrayList<org.jmxtrans.agent.util.json.JsonValue>();
}
/**
* Creates a new JsonArray with the contents of the specified JSON array.
*
* @param array
* the JsonArray to get the initial contents from, must not be <code>null</code>
*/
public JsonArray(JsonArray array) {
this(array, false);
}
private JsonArray(JsonArray array, boolean unmodifiable) {
if (array == null) {
throw new NullPointerException("array is null");
}
if (unmodifiable) {
values = Collections.unmodifiableList(array.values);
} else {
values = new ArrayList<org.jmxtrans.agent.util.json.JsonValue>(array.values);
}
}
/**
* Reads a JSON array from the given reader.
* <p>
* Characters are read in chunks and buffered internally, therefore wrapping an existing reader in
* an additional <code>BufferedReader</code> does <strong>not</strong> improve reading
* performance.
* </p>
*
* @param reader
* the reader to read the JSON array from
* @return the JSON array that has been read
* @throws IOException
* if an I/O error occurs in the reader
* @throws ParseException
* if the input is not valid JSON
* @throws UnsupportedOperationException
* if the input does not contain a JSON array
* @deprecated Use {@link Json#parse(Reader)}{@link org.jmxtrans.agent.util.json.JsonValue#asArray() .asArray()} instead
*/
@Deprecated
public static JsonArray readFrom(Reader reader) throws IOException {
return org.jmxtrans.agent.util.json.JsonValue.readFrom(reader).asArray();
}
/**
* Reads a JSON array from the given string.
*
* @param string
* the string that contains the JSON array
* @return the JSON array that has been read
* @throws ParseException
* if the input is not valid JSON
* @throws UnsupportedOperationException
* if the input does not contain a JSON array
* @deprecated Use {@link Json#parse(String)}{@link org.jmxtrans.agent.util.json.JsonValue#asArray() .asArray()} instead
*/
@Deprecated
public static JsonArray readFrom(String string) {
return org.jmxtrans.agent.util.json.JsonValue.readFrom(string).asArray();
}
/**
* Returns an unmodifiable wrapper for the specified JsonArray. This method allows to provide
* read-only access to a JsonArray.
* <p>
* The returned JsonArray is backed by the given array and reflects subsequent changes. Attempts
* to modify the returned JsonArray result in an <code>UnsupportedOperationException</code>.
* </p>
*
* @param array
* the JsonArray for which an unmodifiable JsonArray is to be returned
* @return an unmodifiable view of the specified JsonArray
*/
public static JsonArray unmodifiableArray(JsonArray array) {
return new JsonArray(array, true);
}
/**
* Appends the JSON representation of the specified <code>int</code> value to the end of this
* array.
*
* @param value
* the value to add to the array
* @return the array itself, to enable method chaining
*/
public JsonArray add(int value) {
values.add(Json.value(value));
return this;
}
/**
* Appends the JSON representation of the specified <code>long</code> value to the end of this
* array.
*
* @param value
* the value to add to the array
* @return the array itself, to enable method chaining
*/
public JsonArray add(long value) {
values.add(Json.value(value));
return this;
}
/**
* Appends the JSON representation of the specified <code>float</code> value to the end of this
* array.
*
* @param value
* the value to add to the array
* @return the array itself, to enable method chaining
*/
public JsonArray add(float value) {
values.add(Json.value(value));
return this;
}
/**
* Appends the JSON representation of the specified <code>double</code> value to the end of this
* array.
*
* @param value
* the value to add to the array
* @return the array itself, to enable method chaining
*/
public JsonArray add(double value) {
values.add(Json.value(value));
return this;
}
/**
* Appends the JSON representation of the specified <code>boolean</code> value to the end of this
* array.
*
* @param value
* the value to add to the array
* @return the array itself, to enable method chaining
*/
public JsonArray add(boolean value) {
values.add(Json.value(value));
return this;
}
/**
* Appends the JSON representation of the specified string to the end of this array.
*
* @param value
* the string to add to the array
* @return the array itself, to enable method chaining
*/
public JsonArray add(String value) {
values.add(Json.value(value));
return this;
}
/**
* Appends the specified JSON value to the end of this array.
*
* @param value
* the JsonValue to add to the array, must not be <code>null</code>
* @return the array itself, to enable method chaining
*/
public JsonArray add(org.jmxtrans.agent.util.json.JsonValue value) {
if (value == null) {
throw new NullPointerException("value is null");
}
values.add(value);
return this;
}
/**
* Replaces the element at the specified position in this array with the JSON representation of
* the specified <code>int</code> value.
*
* @param index
* the index of the array element to replace
* @param value
* the value to be stored at the specified array position
* @return the array itself, to enable method chaining
* @throws IndexOutOfBoundsException
* if the index is out of range, i.e. <code>index < 0</code> or
* <code>index >= size</code>
*/
public JsonArray set(int index, int value) {
values.set(index, Json.value(value));
return this;
}
/**
* Replaces the element at the specified position in this array with the JSON representation of
* the specified <code>long</code> value.
*
* @param index
* the index of the array element to replace
* @param value
* the value to be stored at the specified array position
* @return the array itself, to enable method chaining
* @throws IndexOutOfBoundsException
* if the index is out of range, i.e. <code>index < 0</code> or
* <code>index >= size</code>
*/
public JsonArray set(int index, long value) {
values.set(index, Json.value(value));
return this;
}
/**
* Replaces the element at the specified position in this array with the JSON representation of
* the specified <code>float</code> value.
*
* @param index
* the index of the array element to replace
* @param value
* the value to be stored at the specified array position
* @return the array itself, to enable method chaining
* @throws IndexOutOfBoundsException
* if the index is out of range, i.e. <code>index < 0</code> or
* <code>index >= size</code>
*/
public JsonArray set(int index, float value) {
values.set(index, Json.value(value));
return this;
}
/**
* Replaces the element at the specified position in this array with the JSON representation of
* the specified <code>double</code> value.
*
* @param index
* the index of the array element to replace
* @param value
* the value to be stored at the specified array position
* @return the array itself, to enable method chaining
* @throws IndexOutOfBoundsException
* if the index is out of range, i.e. <code>index < 0</code> or
* <code>index >= size</code>
*/
public JsonArray set(int index, double value) {
values.set(index, Json.value(value));
return this;
}
/**
* Replaces the element at the specified position in this array with the JSON representation of
* the specified <code>boolean</code> value.
*
* @param index
* the index of the array element to replace
* @param value
* the value to be stored at the specified array position
* @return the array itself, to enable method chaining
* @throws IndexOutOfBoundsException
* if the index is out of range, i.e. <code>index < 0</code> or
* <code>index >= size</code>
*/
public JsonArray set(int index, boolean value) {
values.set(index, Json.value(value));
return this;
}
/**
* Replaces the element at the specified position in this array with the JSON representation of
* the specified string.
*
* @param index
* the index of the array element to replace
* @param value
* the string to be stored at the specified array position
* @return the array itself, to enable method chaining
* @throws IndexOutOfBoundsException
* if the index is out of range, i.e. <code>index < 0</code> or
* <code>index >= size</code>
*/
public JsonArray set(int index, String value) {
values.set(index, Json.value(value));
return this;
}
/**
* Replaces the element at the specified position in this array with the specified JSON value.
*
* @param index
* the index of the array element to replace
* @param value
* the value to be stored at the specified array position, must not be <code>null</code>
* @return the array itself, to enable method chaining
* @throws IndexOutOfBoundsException
* if the index is out of range, i.e. <code>index < 0</code> or
* <code>index >= size</code>
*/
public JsonArray set(int index, org.jmxtrans.agent.util.json.JsonValue value) {
if (value == null) {
throw new NullPointerException("value is null");
}
values.set(index, value);
return this;
}
/**
* Removes the element at the specified index from this array.
*
* @param index
* the index of the element to remove
* @return the array itself, to enable method chaining
* @throws IndexOutOfBoundsException
* if the index is out of range, i.e. <code>index < 0</code> or
* <code>index >= size</code>
*/
public JsonArray remove(int index) {
values.remove(index);
return this;
}
/**
* Returns the number of elements in this array.
*
* @return the number of elements in this array
*/
public int size() {
return values.size();
}
/**
* Returns <code>true</code> if this array contains no elements.
*
* @return <code>true</code> if this array contains no elements
*/
public boolean isEmpty() {
return values.isEmpty();
}
/**
* Returns the value of the element at the specified position in this array.
*
* @param index
* the index of the array element to return
* @return the value of the element at the specified position
* @throws IndexOutOfBoundsException
* if the index is out of range, i.e. <code>index < 0</code> or
* <code>index >= size</code>
*/
public org.jmxtrans.agent.util.json.JsonValue get(int index) {
return values.get(index);
}
/**
* Returns a list of the values in this array in document order. The returned list is backed by
* this array and will reflect subsequent changes. It cannot be used to modify this array.
* Attempts to modify the returned list will result in an exception.
*
* @return a list of the values in this array
*/
public List<org.jmxtrans.agent.util.json.JsonValue> values() {
return Collections.unmodifiableList(values);
}
/**
* Returns an iterator over the values of this array in document order. The returned iterator
* cannot be used to modify this array.
*
* @return an iterator over the values of this array
*/
public Iterator<org.jmxtrans.agent.util.json.JsonValue> iterator() {
final Iterator<org.jmxtrans.agent.util.json.JsonValue> iterator = values.iterator();
return new Iterator<org.jmxtrans.agent.util.json.JsonValue>() {
public boolean hasNext() {
return iterator.hasNext();
}
public org.jmxtrans.agent.util.json.JsonValue next() {
return iterator.next();
}
public void remove() {
throw new UnsupportedOperationException();
}
};
}
@Override
void write(org.jmxtrans.agent.util.json.JsonWriter writer) throws IOException {
writer.writeArrayOpen();
Iterator<org.jmxtrans.agent.util.json.JsonValue> iterator = iterator();
if (iterator.hasNext()) {
iterator.next().write(writer);
while (iterator.hasNext()) {
writer.writeArraySeparator();
iterator.next().write(writer);
}
}
writer.writeArrayClose();
}
@Override
public boolean isArray() {
return true;
}
@Override
public JsonArray asArray() {
return this;
}
@Override
public int hashCode() {
return values.hashCode();
}
/**
* Indicates whether a given object is "equal to" this JsonArray. An object is considered equal
* if it is also a <code>JsonArray</code> and both arrays contain the same list of values.
* <p>
* If two JsonArrays are equal, they will also produce the same JSON output.
* </p>
*
* @param object
* the object to be compared with this JsonArray
* @return <tt>true</tt> if the specified object is equal to this JsonArray, <code>false</code>
* otherwise
*/
@Override
public boolean equals(Object object) {
if (this == object) {
return true;
}
if (object == null) {
return false;
}
if (getClass() != object.getClass()) {
return false;
}
JsonArray other = (JsonArray)object;
return values.equals(other.values);
}
}