这个工具通过自动生成解析类，实现了字节数组和对象之间的转换。

1. 使用@ParsePacket注解标注实体类:

@ParsePacket(
        "header:1|cmd:2|len:2|seq:2|mac:6|data:this.len-6|check:1|tail:1"
)
public class TargetObject {
    public byte header;
    public short cmd;
    public short len;
    public short seq;
    public byte[] mac;
    public byte[] data;
    public byte check;
    public byte tail;
}

2. 框架自动生成解析类(<类名>PacketParser)

public class TargetObjectPacketParser {
    public static final TargetObject parse(byte[] src) {
        return parse(src, new TargetObject());
    }

    public static final TargetObject parse(byte[] bytes, TargetObject src) {
        ByteBuffer byteBuffer = ByteBuffer.wrap(bytes);
        src.header = byteBuffer.get();
        src.cmd = byteBuffer.getShort();
        src.len = byteBuffer.getShort();
        src.seq = byteBuffer.getShort();
        src.mac = new byte[6];
        byteBuffer.get(src.mac);
        src.data = new byte[src.len-6];
        byteBuffer.get(src.data);
        src.check = byteBuffer.get();
        src.tail = byteBuffer.get();
        return src;
    }

    public static final byte[] toBytes(TargetObject src) {
        ByteBuffer byteBuffer = ByteBuffer.allocate(1 + 2 + 2 + 2 + 6 + src.len-6 + 1 + 1);
        byteBuffer.put(src.header);
        byteBuffer.putShort(src.cmd);
        byteBuffer.putShort(src.len);
        byteBuffer.putShort(src.seq);
        byteBuffer.put(src.mac);
        byteBuffer.put(src.data);
        byteBuffer.put(src.check);
        byteBuffer.put(src.tail);
        return byteBuffer.array();
    }
}

3. 使用方法:

String data = "AA11220008556677889911223344556677";
byte[] bytes = hexToBytes(data);
// bytes to object
TargetObject targetObject = TargetObjectPacketParser.parse(bytes); // suffix with "PacketParser"
//object to bytes
byte[] toBytes = TargetObjectPacketParser.toBytes(targetObject);

gradle

compile 'com.legendmohe.maven:packetparser-annonation:0.1'
apt 'com.legendmohe.maven:packetparser-complier:0.1'