protected static int codePointAt()

in google-http-client/src/main/java/com/google/api/client/util/escape/UnicodeEscaper.java [220:246]

• 24 lines of code
• 6 McCabe index (conditional complexity)

  protected static int codePointAt(CharSequence seq, int index, int end) {
    if (index < end) {
      char c1 = seq.charAt(index++);
      if (c1 < Character.MIN_HIGH_SURROGATE || c1 > Character.MAX_LOW_SURROGATE) {
        // Fast path (first test is probably all we need to do)
        return c1;
      } else if (c1 <= Character.MAX_HIGH_SURROGATE) {
        // If the high surrogate was the last character, return its inverse
        if (index == end) {
          return -c1;
        }
        // Otherwise look for the low surrogate following it
        char c2 = seq.charAt(index);
        if (Character.isLowSurrogate(c2)) {
          return Character.toCodePoint(c1, c2);
        }
        throw new IllegalArgumentException(
            "Expected low surrogate but got char '" + c2 + "' with value " + (int) c2 + " at index "
                + index);
      } else {
        throw new IllegalArgumentException(
            "Unexpected low surrogate character '" + c1 + "' with value " + (int) c1 + " at index "
                + (index - 1));
      }
    }
    throw new IndexOutOfBoundsException("Index exceeds specified range");
  }