/*******************************************************************************
* Copyright 2011 See AUTHORS file.
*
* 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.badlogic.gdx.utils;
import java.io.Closeable;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.OutputStream;
/** Builder style API for emitting UBJSON.
* @author Justin Shapcott */
public class UBJsonWriter implements Closeable {
final DataOutputStream out;
private JsonObject current;
private boolean named;
private final Array<JsonObject> stack = new Array();
public UBJsonWriter (OutputStream out) {
if (!(out instanceof DataOutputStream)) out = new DataOutputStream(out);
this.out = (DataOutputStream)out;
}
/** Begins a new object container. To finish the object call {@link #pop()}.
* @return This writer, for chaining */
public UBJsonWriter object () throws IOException {
if (current != null) {
if (!current.array) {
if (!named) throw new IllegalStateException("Name must be set.");
named = false;
}
}
stack.add(current = new JsonObject(false));
return this;
}
/** Begins a new named object container, having the given name. To finish the object call {@link #pop()}.
* @return This writer, for chaining */
public UBJsonWriter object (String name) throws IOException {
name(name).object();
return this;
}
/** Begins a new array container. To finish the array call {@link #pop()}.
* @return this writer, for chaining. */
public UBJsonWriter array () throws IOException {
if (current != null) {
if (!current.array) {
if (!named) throw new IllegalStateException("Name must be set.");
named = false;
}
}
stack.add(current = new JsonObject(true));
return this;
}
/** Begins a new named array container, having the given name. To finish the array call {@link #pop()}.
* @return this writer, for chaining. */
public UBJsonWriter array (String name) throws IOException {
name(name).array();
return this;
}
/** Appends a name for the next object, array, or value.
* @return this writer, for chaining */
public UBJsonWriter name (String name) throws IOException {
if (current == null || current.array) throw new IllegalStateException("Current item must be an object.");
byte[] bytes = name.getBytes("UTF-8");
if (bytes.length <= Byte.MAX_VALUE) {
out.writeByte('i');
out.writeByte(bytes.length);
} else if (bytes.length <= Short.MAX_VALUE) {
out.writeByte('I');
out.writeShort(bytes.length);
} else {
out.writeByte('l');
out.writeInt(bytes.length);
}
out.write(bytes);
named = true;
return this;
}
/** Appends a {@code byte} value to the stream. This corresponds to the {@code int8} value type in the UBJSON specification.
* @return this writer, for chaining */
public UBJsonWriter value (byte value) throws IOException {
checkName();
out.writeByte('i');
out.writeByte(value);
return this;
}
/** Appends a {@code short} value to the stream. This corresponds to the {@code int16} value type in the UBJSON specification.
* @return this writer, for chaining */
public UBJsonWriter value (short value) throws IOException {
checkName();
out.writeByte('I');
out.writeShort(value);
return this;
}
/** Appends an {@code int} value to the stream. This corresponds to the {@code int32} value type in the UBJSON specification.
* @return this writer, for chaining */
public UBJsonWriter value (int value) throws IOException {
checkName();
out.writeByte('l');
out.writeInt(value);
return this;
}
/** Appends a {@code long} value to the stream. This corresponds to the {@code int64} value type in the UBJSON specification.
* @return this writer, for chaining */
public UBJsonWriter value (long value) throws IOException {
checkName();
out.writeByte('L');
out.writeLong(value);
return this;
}
/** Appends a {@code float} value to the stream. This corresponds to the {@code float32} value type in the UBJSON specification.
* @return this writer, for chaining */
public UBJsonWriter value (float value) throws IOException {
checkName();
out.writeByte('d');
out.writeFloat(value);
return this;
}
/** Appends a {@code double} value to the stream. This corresponds to the {@code float64} value type in the UBJSON
* specification.
* @return this writer, for chaining */
public UBJsonWriter value (double value) throws IOException {
checkName();
out.writeByte('D');
out.writeDouble(value);
return this;
}
/** Appends a {@code boolean} value to the stream. This corresponds to the {@code boolean} value type in the UBJSON
* specification.
* @return this writer, for chaining */
public UBJsonWriter value (boolean value) throws IOException {
checkName();
out.writeByte(value ? 'T' : 'F');
return this;
}
/** Appends a {@code char} value to the stream. Because, in Java, a {@code char} is 16 bytes, this corresponds to the
* {@code int16} value type in the UBJSON specification.
* @return this writer, for chaining */
public UBJsonWriter value (char value) throws IOException {
checkName();
out.writeByte('I');
out.writeChar(value);
return this;
}
/** Appends a {@code String} value to the stream. This corresponds to the {@code string} value type in the UBJSON specification.
* @return this writer, for chaining */
public UBJsonWriter value (String value) throws IOException {
checkName();
byte[] bytes = value.getBytes("UTF-8");
out.writeByte('S');
if (bytes.length <= Byte.MAX_VALUE) {
out.writeByte('i');
out.writeByte(bytes.length);
} else if (bytes.length <= Short.MAX_VALUE) {
out.writeByte('I');
out.writeShort(bytes.length);
} else {
out.writeByte('l');
out.writeInt(bytes.length);
}
out.write(bytes);
return this;
}
/** Appends an optimized {@code byte array} value to the stream. As an optimized array, the {@code int8} value type marker and
* element count are encoded once at the array marker instead of repeating the type marker for each element.
* @return this writer, for chaining */
public UBJsonWriter value (byte[] values) throws IOException {
array();
out.writeByte('$');
out.writeByte('i');
out.writeByte('#');
value(values.length);
for (int i = 0, n = values.length; i < n; i++) {
out.writeByte(values[i]);
}
pop(true);
return this;
}
/** Appends an optimized {@code short array} value to the stream. As an optimized array, the {@code int16} value type marker and
* element count are encoded once at the array marker instead of repeating the type marker for each element.
* @return this writer, for chaining */
public UBJsonWriter value (short[] values) throws IOException {
array();
out.writeByte('$');
out.writeByte('I');
out.writeByte('#');
value(values.length);
for (int i = 0, n = values.length; i < n; i++) {
out.writeShort(values[i]);
}
pop(true);
return this;
}
/** Appends an optimized {@code int array} value to the stream. As an optimized array, the {@code int32} value type marker and
* element count are encoded once at the array marker instead of repeating the type marker for each element.
* @return this writer, for chaining */
public UBJsonWriter value (int[] values) throws IOException {
array();
out.writeByte('$');
out.writeByte('l');
out.writeByte('#');
value(values.length);
for (int i = 0, n = values.length; i < n; i++) {
out.writeInt(values[i]);
}
pop(true);
return this;
}
/** Appends an optimized {@code long array} value to the stream. As an optimized array, the {@code int64} value type marker and
* element count are encoded once at the array marker instead of repeating the type marker for each element.
* @return this writer, for chaining */
public UBJsonWriter value (long[] values) throws IOException {
array();
out.writeByte('$');
out.writeByte('L');
out.writeByte('#');
value(values.length);
for (int i = 0, n = values.length; i < n; i++) {
out.writeLong(values[i]);
}
pop(true);
return this;
}
/** Appends an optimized {@code float array} value to the stream. As an optimized array, the {@code float32} value type marker
* and element count are encoded once at the array marker instead of repeating the type marker for each element.
* @return this writer, for chaining */
public UBJsonWriter value (float[] values) throws IOException {
array();
out.writeByte('$');
out.writeByte('d');
out.writeByte('#');
value(values.length);
for (int i = 0, n = values.length; i < n; i++) {
out.writeFloat(values[i]);
}
pop(true);
return this;
}
/** Appends an optimized {@code double array} value to the stream. As an optimized array, the {@code float64} value type marker
* and element count are encoded once at the array marker instead of repeating the type marker for each element. element count
* are encoded once at the array marker instead of for each element.
* @return this writer, for chaining */
public UBJsonWriter value (double[] values) throws IOException {
array();
out.writeByte('$');
out.writeByte('D');
out.writeByte('#');
value(values.length);
for (int i = 0, n = values.length; i < n; i++) {
out.writeDouble(values[i]);
}
pop(true);
return this;
}
/** Appends a {@code boolean array} value to the stream.
* @return this writer, for chaining */
public UBJsonWriter value (boolean[] values) throws IOException {
array();
for (int i = 0, n = values.length; i < n; i++) {
out.writeByte(values[i] ? 'T' : 'F');
}
pop();
return this;
}
/** Appends an optimized {@code char array} value to the stream. As an optimized array, the {@code int16} value type marker and
* element count are encoded once at the array marker instead of repeating the type marker for each element.
* @return this writer, for chaining */
public UBJsonWriter value (char[] values) throws IOException {
array();
out.writeByte('$');
out.writeByte('C');
out.writeByte('#');
value(values.length);
for (int i = 0, n = values.length; i < n; i++) {
out.writeChar(values[i]);
}
pop(true);
return this;
}
/** Appends an optimized {@code String array} value to the stream. As an optimized array, the {@code String} value type marker
* and element count are encoded once at the array marker instead of repeating the type marker for each element.
* @return this writer, for chaining */
public UBJsonWriter value (String[] values) throws IOException {
array();
out.writeByte('$');
out.writeByte('S');
out.writeByte('#');
value(values.length);
for (int i = 0, n = values.length; i < n; i++) {
byte[] bytes = values[i].getBytes("UTF-8");
if (bytes.length <= Byte.MAX_VALUE) {
out.writeByte('i');
out.writeByte(bytes.length);
} else if (bytes.length <= Short.MAX_VALUE) {
out.writeByte('I');
out.writeShort(bytes.length);
} else {
out.writeByte('l');
out.writeInt(bytes.length);
}
out.write(bytes);
}
pop(true);
return this;
}
/** Appends the given JsonValue, including all its fields recursively, to the stream.
* @return this writer, for chaining */
public UBJsonWriter value (JsonValue value) throws IOException {
if (value.isObject()) {
if (value.name != null)
object(value.name);
else
object();
for (JsonValue child = value.child; child != null; child = child.next)
value(child);
pop();
} else if (value.isArray()) {
if (value.name != null)
array(value.name);
else
array();
for (JsonValue child = value.child; child != null; child = child.next)
value(child);
pop();
} else if (value.isBoolean()) {
if (value.name != null) name(value.name);
value(value.asBoolean());
} else if (value.isDouble()) {
if (value.name != null) name(value.name);
value(value.asDouble());
} else if (value.isLong()) {
if (value.name != null) name(value.name);
value(value.asLong());
} else if (value.isString()) {
if (value.name != null) name(value.name);
value(value.asString());
} else if (value.isNull()) {
if (value.name != null) name(value.name);
value();
} else {
throw new IOException("Unhandled JsonValue type");
}
return this;
}
/** Appends the object to the stream, if it is a known value type. This is a convenience method that calls through to the
* appropriate value method.
* @return this writer, for chaining */
public UBJsonWriter value (Object object) throws IOException {
if (object == null) {
return value();
} else if (object instanceof Number) {
Number number = (Number)object;
if (object instanceof Byte) return value(number.byteValue());
if (object instanceof Short) return value(number.shortValue());
if (object instanceof Integer) return value(number.intValue());
if (object instanceof Long) return value(number.longValue());
if (object instanceof Float) return value(number.floatValue());
if (object instanceof Double) return value(number.doubleValue());
} else if (object instanceof Character) {
return value(((Character)object).charValue());
} else if (object instanceof CharSequence) {
return value(object.toString());
} else
throw new IOException("Unknown object type.");
return this;
}
/** Appends a {@code null} value to the stream.
* @return this writer, for chaining */
public UBJsonWriter value () throws IOException {
checkName();
out.writeByte('Z');
return this;
}
/** Appends a named {@code byte} value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, byte value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code short} value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, short value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code int} value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, int value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code long} value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, long value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code float} value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, float value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code double} value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, double value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code boolean} value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, boolean value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code char} value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, char value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code String} value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, String value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code byte} array value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, byte[] value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code short} array value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, short[] value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code int} array value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, int[] value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code long} array value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, long[] value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code float} array value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, float[] value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code double} array value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, double[] value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code boolean} array value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, boolean[] value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code char} array value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, char[] value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code String} array value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name, String[] value) throws IOException {
return name(name).value(value);
}
/** Appends a named {@code null} array value to the stream.
* @return this writer, for chaining */
public UBJsonWriter set (String name) throws IOException {
return name(name).value();
}
private void checkName () {
if (current != null) {
if (!current.array) {
if (!named) throw new IllegalStateException("Name must be set.");
named = false;
}
}
}
/** Ends the current object or array and pops it off of the element stack.
* @return This writer, for chaining */
public UBJsonWriter pop () throws IOException {
return pop(false);
}
protected UBJsonWriter pop (boolean silent) throws IOException {
if (named) throw new IllegalStateException("Expected an object, array, or value since a name was set.");
if (silent)
stack.pop();
else
stack.pop().close();
current = stack.size == 0 ? null : stack.peek();
return this;
}
/** Flushes the underlying stream. This forces any buffered output bytes to be written out to the stream. */
public void flush () throws IOException {
out.flush();
}
/** Closes the underlying output stream and releases any system resources associated with the stream. */
public void close () throws IOException {
while (stack.size > 0)
pop();
out.close();
}
private class JsonObject {
final boolean array;
JsonObject (boolean array) throws IOException {
this.array = array;
out.writeByte(array ? '[' : '{');
}
void close () throws IOException {
out.writeByte(array ? ']' : '}');
}
}
}