java-binary-block-parser | dynamic way to process binary data | Parser library

Read about Endianness. Java is big-endian. This means that your example is wrong. Instead of inserting the zero string (00000000) after position 3 in the target byte, your example demonstrates inserting the zero string either after position 6 or before position 5 (see bit numbering below).

The operation you are looking for is called "left shift". Here is a link discussing Bitwise and Bit Shift Operators.

Here is the strategy you want to use:

1. Determine how many bits to shift from the target into the destination. I will call this the initialShiftCount. In your example, the initialShiftCount is 3 bits.
2. Left shift the initialShiftCount number of bits into the destination.
3. Left shift all 8 bits from the insert string into the destination.
4. Left shift the remaining bits from the target into the destination.

Terms: destination - the location into which you want to place the combination of the bits in the insert string and the target. In your example, this is the variable that ends up holding the string 1110000000011111'.
*insert string* - the bits you want to insert into the target bits. In your example, the insert string is00000000.
*target* - the bits into which you want to insert the insert string. In your example, the target is11111111`.

Bit Numbering In a big-endian system, the bits are numbered as follows: 87654321