JsonObjectDecoder.java — netty Source File

Source Code

/*
 * Copyright 2014 The Netty Project
 *
 * The Netty Project licenses this file to you 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:
 *
 *   https://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 io.netty.handler.codec.json;

import static io.netty.util.internal.ObjectUtil.checkPositive;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufUtil;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.ByteToMessageDecoder;
import io.netty.handler.codec.CorruptedFrameException;
import io.netty.handler.codec.TooLongFrameException;
import io.netty.channel.ChannelPipeline;

import java.util.List;

/**
 * Splits a byte stream of JSON objects and arrays into individual objects/arrays and passes them up the
 * {@link ChannelPipeline}.
 * <p>
 * The byte stream is expected to be in UTF-8 character encoding or ASCII. The current implementation
 * uses direct {@code byte} to {@code char} cast and then compares that {@code char} to a few low range
 * ASCII characters like {@code '{'}, {@code '['} or {@code '"'}. UTF-8 is not using low range [0..0x7F]
 * byte values for multibyte codepoint representations therefore fully supported by this implementation.
 * <p>
 * This class does not do any real parsing or validation. A sequence of bytes is considered a JSON object/array
 * if it contains a matching number of opening and closing braces/brackets. It's up to a subsequent
 * {@link ChannelHandler} to parse the JSON text into a more usable form i.e. a POJO.
 */
public class JsonObjectDecoder extends ByteToMessageDecoder {

    private static final int ST_CORRUPTED = -1;
    private static final int ST_INIT = 0;
    private static final int ST_DECODING_NORMAL = 1;
    private static final int ST_DECODING_ARRAY_STREAM = 2;

    private int openBraces;
    private int idx;

    private int lastReaderIndex;

    private int state;
    private boolean insideString;

    private final int maxObjectLength;
    private final boolean streamArrayElements;
// ... (178 more lines)