parquet-common/src/main/java/org/apache/parquet/bytes/BytesUtils.java
public static int readIntLittleEndian(ByteBuffer in, int offset) throws IOException {
    int ch4 = in.get(offset) & 0xff;
    int ch3 = in.get(offset + 1) & 0xff;
    int ch2 = in.get(offset + 2) & 0xff;
    int ch1 = in.get(offset + 3) & 0xff;
    return ((ch1 << 24) + (ch2 << 16) + (ch3 << 8) + (ch4 << 0));
  }
public static int readIntLittleEndian(ByteBuffer in, int offset) throws IOException {
    int ch4 = in.get(offset) & 0xff;
    int ch3 = in.get(offset + 1) & 0xff;
    int ch2 = in.get(offset + 2) & 0xff;
    int ch1 = in.get(offset + 3) & 0xff;
    return ((ch1 << 24) + (ch2 << 16) + (ch3 << 8) + (ch4 << 0));
  }
reads an int in little endian at the given position
@param in a byte buffer
@param offset an offset into the byte buffer
@return the integer at position offset read using little endian byte order
@throws IOException if there is an exception reading from the byte buffer