* of several definitions of "whitespace"</a>.)
   *
   * <p>All Unicode White_Space characters are on the BMP and thus supported by this API.
   *
   * <p><b>Note:</b> as the Unicode definition evolves, we will modify this matcher to keep it up to
   * date.
   *
   * @since 19.0 (since 1.0 as constant {@code WHITESPACE})
   */
  public static CharMatcher whitespace() {
    return Whitespace.INSTANCE;
  }

  /**

   * of several definitions of "whitespace"</a>.)
   *
   * <p>All Unicode White_Space characters are on the BMP and thus supported by this API.
   *
   * <p><b>Note:</b> as the Unicode definition evolves, we will modify this matcher to keep it up to
   * date.
   *
   * @since 19.0 (since 1.0 as constant {@code WHITESPACE})
   */
  public static CharMatcher whitespace() {
    return Whitespace.INSTANCE;
  }

  /**

      var whitespace = false
      afterBoundaryLoop@while (true) {
        when (source.select(afterBoundaryOptions)) {
          0 -> {
            // "\r\n": We've found a new part.
            partCount++
            break@afterBoundaryLoop
          }

          1 -> {
            // "--": No more parts.

            return Stream.of(
                    Arguments.of(null, "null version"),
                    Arguments.of("", "empty version"),
                    Arguments.of("   ", "whitespace-only version"),
                    Arguments.of("4", "incomplete version (major only)"),
                    Arguments.of("4.0", "incomplete version (major.minor only)"),

        while (st.hasMoreElements()) {
            list.add(st.nextElement().toString());
        }
        return list.toArray(new String[list.size()]);
    }

    /**
     * Removes whitespace from the left side of the string.
     *
     * @param text
     *            The text to trim
     * @return The resulting string
     */
    public static final String ltrim(final String text) {

    /**
     * Process a single line: remove comments, trim whitespace, and replace placeholders.
     */
    private static String processLine(String line, String mavenProjectBasedir) {
        // Remove comments
        int commentIndex = line.indexOf('#');
        if (commentIndex >= 0) {
            line = line.substring(0, commentIndex);
        }

        // Trim whitespace
        line = line.trim();

Fixer tool expects comments that follow specific pattern:

- For hash-style comments: comment starts with `# ` (hash following by whitespace) in the beginning of the string or after a whitespace.
- For slash-style comments: comment starts with `// ` (two slashes following by whitespace) in the beginning of the string or after a whitespace.

If comment doesn't follow this pattern, fixer tool will not preserve it.

```python
#Function declaration

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.io;

import static com.google.common.base.CharMatcher.whitespace;
import static com.google.common.truth.Truth.assertThat;
import static java.nio.charset.StandardCharsets.US_ASCII;
import static java.nio.charset.StandardCharsets.UTF_8;
import static org.junit.Assert.assertThrows;

                "word1\n" + "  \n" + // whitespace line (may be treated as content)
                "# Another comment\n" + "word2\n";

        // Write content to test file
        writeTestFile(content);

        // Reload and verify
        protwordsFile.reload(null);

        PagingList<ProtwordsItem> result = protwordsFile.selectList(0, 10);
        // Whitespace-only lines may be treated as entries

    @DisplayName("Edge Cases")
    class EdgeCases {

        @Test
        @DisplayName("should handle POM with only whitespace elements")
        void shouldHandlePOMWithWhitespaceElements() throws Exception {
            String pomXml = PomBuilder.create()
                    .groupId("   ") // whitespace-only groupId
                    .artifactId("test-project")
                    .version("1.0.0")
                    .build();