org.jboss.netty.handler.codec.marshalling.LimitingByteInput Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of netty Show documentation

The Netty project is an effort to provide an asynchronous event-driven network application framework and tools for rapid development of maintainable high performance and high scalability protocol servers and clients. In other words, Netty is a NIO client server framework which enables quick and easy development of network applications such as protocol servers and clients. It greatly simplifies and streamlines network programming such as TCP and UDP socket server.

There is a newer version: 4.0.0.Alpha8

Show newest version

/*
 * Copyright 2012 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:
 *
 *   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 org.jboss.netty.handler.codec.marshalling;

import java.io.IOException;

import org.jboss.marshalling.ByteInput;

/**
 * {@link ByteInput} implementation which wraps another {@link ByteInput} and throws a {@link TooBigObjectException}
 * if the read limit was reached.
 *
 *
 */
class LimitingByteInput implements ByteInput {

    // Use a static instance here to remove the overhead of fillStacktrace
    private static final TooBigObjectException EXCEPTION = new TooBigObjectException();

    private final ByteInput input;
    private final long limit;
    private long read;

    public LimitingByteInput(ByteInput input, long limit) {
        if (limit <= 0) {
            throw new IllegalArgumentException("The limit MUST be > 0");
        }
        this.input = input;
        this.limit = limit;
    }

    public void close() throws IOException {
        // Nothing todo
    }

    public int available() throws IOException {
        int available = input.available();
        int readable = readable(available);
        return readable;
    }

    public int read() throws IOException {
        int readable = readable(1);
        if (readable > 0) {
            int b = input.read();
            read++;
            return b;
        } else {
            throw EXCEPTION;
        }
    }

    public int read(byte[] array) throws IOException {
        return read(array, 0, array.length);
    }

    public int read(byte[] array, int offset, int length) throws IOException {
        int readable = readable(length);
        if (readable > 0) {
            int i = input.read(array, offset, readable);
            read += i;
            return i;
        } else {
            throw EXCEPTION;
        }
    }

    public long skip(long bytes) throws IOException {
        int readable = readable((int) bytes);
        if (readable > 0) {
            long i = input.skip(readable);
            read += i;
            return i;
        } else {
            throw EXCEPTION;
        }
    }

    private int readable(int length) {
        return (int) Math.min(length, limit - read);
    }

    /**
     * Exception that will get thrown if the {@link Object} is to big to unmarshall
     *
     */
    static final class TooBigObjectException extends IOException {
        private static final long serialVersionUID = 1L;
    }
}