在netty4中，ByteBuf有一个方法读取unsigned int little endian
/**
* Gets an unsigned 32-bit integer at the current {@code readerIndex}
* in the Little Endian Byte Order and increases the {@code readerIndex}
* by {@code 4} in this buffer.
*
* @throws IndexOutOfBoundsException
* if {@code this.readableBytes} is less than {@code 4}
*/
public abstract long readUnsignedIntLE();
如何用ByteBuf写一个32位无符号数Little Endian Byte Order？