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This noncompliant code example attempts to read 1024 bytes encoded in UTF-8 from an InputStream and return them as a String. It explicitly specifies the character encoding used to build the string, in compliance with rule IDS13STR04-J. Use compatible encodings on both sides of file or network IOcharacter encodings when communicating string data between JVMs.

public static String readBytes(InputStream in) throws IOException {
  byte[] data = new byte[1024];
  if (in.read(data) == -1) {
    throw new EOFException();
  }
  return new String(data, "UTF-8");
}

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This compliant solution reads all the desired bytes into its buffer, accounting for the total number of bytes read and adjusting the remaining bytes' offset, consequently ensuring that the required data is read in full. It also avoids splitting multibyte encoded characters across buffers by deferring construction of the result string until the data has been fully read. (See rule IDS10-J. Do not assume every character in a string is the same size for more information.)

public static String readBytes(InputStream in) throws IOException {
  int offset = 0;
  int bytesRead = 0;
  byte[] data = new byte[1024];
  while ((bytesRead = in.read(data, offset, data.length - offset))
    != -1) {
    offset += bytesRead;
    if (offset >= data.length) {
      break;
    }
  }
  String str = new String(data, "UTF-8");
  return str;
}

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