C structure available in Java

Question

I have a C structure that is sent over some intermediate networks and receives Java code through a serial link. Java code gives me an array of bytes, which I now want to repackage as the source structure. Now, if the receipt code was in C, it was simple. Is there an easy way to repack byte [] in java for structure C. I have minimal experience with java, but this does not seem to be a common problem or not resolved in any frequently asked questions that I can find.

FYI structure C

struct data {
     uint8_t        moteID;
    uint8_t     status; //block or not
    uint16_t   tc_1;
    uint16_t   tc_2;
    uint16_t   panelTemp;  //board temp
    uint16_t   epoch#;
    uint16_t   count;    //pkt seq since the start of epoch
    uint16_t   TEG_v;   
    int16_t   TEG_c;    
 }data;

Answer 1

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public class Data {

    private byte moteId;
    private byte status;
    private short tc_1;
    private short tc_2;
    //...etc...
    private int tc_2_as_int;

    private Data() {
        // empty
    }

    public static Data createFromBytes(byte[] bytes) throws IOException {
        final Data data = new Data();
        final ByteBuffer buf = ByteBuffer.wrap(bytes);

        // If needed...
        //buf.order(ByteOrder.LITTLE_ENDIAN);

        data.moteId = buf.get();
        data.status = buf.get();
        data.tc_1 = buf.getShort();
        data.tc_2 = buf.getShort();
        // ...extract other fields here

        // Example to convert unsigned short to a positive int
        data.tc_2_as_int = buf.getShort() & 0xffff;

        return data;        
    }

}

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Answer 2

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class Data
{
    public int        moteID;
    public int        status; //block or not
    public int        tc_1;
    public int        tc_2;
}

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Data convertBytesToData(byte[] dataToConvert)
{
    Data d = Data();
    d.moteId = (int)dataToConvert[0];
    d.status = (int)dataToConvert[1];
    d.tc_1 = ((int)dataToConvert[2] << 8) + dataTocConvert[3];  // unpacking 16-bits
    d.tc_2 = ((int)dataToConvert[4] << 8) + dataTocConvert[5];  // unpacking 16-bits
}

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Answer 3

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Answer 4

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