if (Character.isDigit(hostname.charAt(0))) {
            int i, len, dots;
            char[] data;

            i = dots = 0; /* quick IP address validation */
            len = hostname.length();
            data = hostname.toCharArray();
            while (i < len && Character.isDigit(data[i++])) {
                if (i == len && dots == 3) {
                    // probably an IP address
                    return true;

 * label is longer than 63 characters. Trailing dots are okay.
 */
internal fun String.containsInvalidLabelLengths(): Boolean {
  if (length !in 1..253) return true

  var labelStart = 0
  while (true) {
    val dot = indexOf('.', startIndex = labelStart)
    val labelLength =
      when (dot) {
        -1 -> length - labelStart
        else -> dot - labelStart
      }
    if (labelLength !in 1..63) return true

        if (Character.isDigit(this.calledName.charAt(0))) {
            int i, len, dots;
            char[] data;

            i = dots = 0; /* quick IP address validation */
            len = this.calledName.length();
            data = this.calledName.toCharArray();
            while (i < len && Character.isDigit(data[i++])) {
                if (i == len && dots == 3) {
                    // probably an IP address

    <_comment>Office Open XML Document</_comment>
    <glob pattern="*.docx"/>
    <sub-class-of type="application/x-tika-ooxml"/>
  </mime-type>

  <mime-type type="application/vnd.openxmlformats-officedocument.wordprocessingml.template">
    <_comment>Office Open XML Document Template</_comment>
    <glob pattern="*.dotx"/>
    <sub-class-of type="application/x-tika-ooxml"/>
  </mime-type>

            int i, len, dots;
            char[] data;

            i = dots = 0; /* quick IP address validation */
            len = hostname.length();
            data = hostname.toCharArray();
            while (i < len && Character.isDigit(data[i++])) {
                if (i == len && dots == 3) {
                    // probably an IP address
                    return true;

/**
 * Tests for SpnegoConstants interface.
 * Verifies constant values, modifiers, types, and structural properties.
 */
class SpnegoConstantsTest {

    // Simple OID format: numbers separated by dots (at least one dot)
    private static final Pattern OID_PATTERN = Pattern.compile("\\d+(?:\\.\\d+)+");

    @Test
    @DisplayName("Constant values match expected OIDs")
    void constantValues() {

        // Normal extensions should be allowed
        assertEquals("\\share\\file.txt", validator.validatePath("\\share\\file.txt"));
        assertEquals("\\share\\document.docx", validator.validatePath("\\share\\document.docx"));
        assertEquals("\\share\\archive.tar.gz", validator.validatePath("\\share\\archive.tar.gz"));
    }

    @Test
    public void testInternationalCharacters() throws Exception {

Remember how our app/file structure looks like:

<img src="/img/tutorial/bigger-applications/package.drawio.svg">

---

The two dots `..`, like in:

```Python
from ..dependencies import get_token_header
```

mean:

* Starting in the same package that this module (the file `app/routers/items.py`) lives in (the directory `app/routers/`)...

1E65          ; valid                                  # 1.1  LATIN SMALL LETTER S WITH ACUTE AND DOT ABOVE
1E66          ; mapped                 ; 1E67          # 1.1  LATIN CAPITAL LETTER S WITH CARON AND DOT ABOVE
1E67          ; valid                                  # 1.1  LATIN SMALL LETTER S WITH CARON AND DOT ABOVE
1E68          ; mapped                 ; 1E69          # 1.1  LATIN CAPITAL LETTER S WITH DOT BELOW AND DOT ABOVE

        if (Character.isDigit(calledName.charAt(0))) {
            int i, len, dots;
            char[] data;

            i = dots = 0; /* quick IP address validation */
            len = calledName.length();
            data = calledName.toCharArray();
            while (i < len && Character.isDigit(data[i++])) {
                if (i == len && dots == 3) {
                    // probably an IP address