Jad Decompile Error With Shift Operators.

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I found sometime jad has bug in decompile the code. Like the following code:

Code frame 1: long2Bytes

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// this code is for convert long to bytes.
// long2Bytes(0x12345670, 1) => 0x1
// long2Bytes(0x12345670, 2) => 0x12
public static final byte[] long2Bytes(long l, int len) {
    if (len < 0) {
        return null;
    } else {
        if (len > 8) {
            len = 8;
        }

        byte[] temp = new byte[len];
        int i = len - 1;

        for(int j = 0; i >= 0; ++j) {
            temp[j] = (byte)((int)(l >>> (i << 3)));
            --i;
        }

        return temp;
    }
}

Decompile this code will be:

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public static final byte[] long2Bytes(long l, int len) {
    if (len < 0) {
        return null;
    } else {
        if (len > 8) {
            len = 8;
        }

        byte[] temp = new byte[len];
        int i = len - 1;

        for(int j = 0; i >= 0; ++j) {
            temp[j] = (byte)((int)(l >>> i << 3));
            --i;
        }

        return temp;
    }
}


You will see the byte shift operator>>> << are wrong.

Code frame 2: bytes2Long

I find another mistake in Jad is:

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public static final long bytes2Long(byte[] b) {
  if (b.length <= 0 || b.length > 8) {
      throw new IllegalArgumentException("byte length should be 1~8bytes.");
  }
     
  long l = 0L;
  for (int i = 0, j = b.length - 1; i <= j; i++) {
      l |= (b[i] & 0xFF) << ((j - i) << 3);
  }
    
  return l;
}

Decompile this code will be:

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public static final long bytes2Long(byte[] b) {
    if (b.length <= 0 || b.length > 8)
      throw new IllegalArgumentException("byte length should be 1~8bytes."); 
    long l = 0L;
    for (int i = 0, j = b.length - 1; i <= j; i++)
      l |= (b[i] & 0xFF) << j - i << 3;
    return l;
  }


Conclusion

You will see the byte shift operator>>> << are wrong again.
So if you want decompile some code, be careful with shift operators.