String simple = "a,b,c";
    List<String> letters = COMMA_SPLITTER.splitToList(simple);
    assertThat(letters).containsExactly("a", "b", "c").inOrder();
  }

  public void testCharacterSimpleSplitToStream() {
    String simple = "a,b,c";
    List<String> letters = COMMA_SPLITTER.splitToStream(simple).collect(toImmutableList());
    assertThat(letters).containsExactly("a", "b", "c").inOrder();
  }

     */
    private CharUtil() {
    }

    /**
     * Checks if the given character is a valid URL character.
     *
     * Valid URL characters include:
     * - Lowercase letters (a-z)
     * - Uppercase letters (A-Z)
     * - Digits (0-9)
     * - Special characters: . - * _ : / + % = & ? # [ ] @ ~ ! $ ' ( ) , ;
     *
     * @param c the character to check

But then the attackers try with username `stanleyjobsox` and password `love123`.

And your application code does something like:

```Python

      notJar.delete();
    }
  }

  public void testGetClassPathEntry() throws MalformedURLException, URISyntaxException {
    if (isWindows()) {
      return; // TODO: b/136041958 - We need to account for drive letters in the path.
    }
    assertEquals(
        new File("/usr/test/dep.jar").toURI(),
        ClassPath.getClassPathEntry(new File("/home/build/outer.jar"), "file:/usr/test/dep.jar")
            .toURI());

          // Canonical escaper method that only escapes lower case ASCII letters.
          @Override
          protected char @Nullable [] escape(int cp) {
            return ('a' <= cp && cp <= 'z') ? new char[] {Character.toUpperCase((char) cp)} : null;
          }

          // Inefficient implementation that defines all letters as escapable.
          @Override

          // Canonical escaper method that only escapes lower case ASCII letters.
          @Override
          protected char @Nullable [] escape(int cp) {
            return ('a' <= cp && cp <= 'z') ? new char[] {Character.toUpperCase((char) cp)} : null;
          }

          // Inefficient implementation that defines all letters as escapable.
          @Override

	}
	return Map(unicode.ToLower, s)
}

// ToTitle treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their title case.
func ToTitle(s []byte) []byte { return Map(unicode.ToTitle, s) }

// ToUpperSpecial treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their
// upper case, giving priority to the special casing rules.

Also, HTTP headers are case-insensitive, so, you can declare them with standard Python style (also known as "snake_case").

So, you can use `user_agent` as you normally would in Python code, instead of needing to capitalize the first letters as `User_Agent` or something similar.

If for some reason you need to disable automatic conversion of underscores to hyphens, set the parameter `convert_underscores` of `Header` to `False`:

        assertEquals("Hello", tokens.get(0).getTerm());
        assertEquals("world", tokens.get(1).getTerm());
        assertEquals("How", tokens.get(2).getTerm());
        assertEquals("are", tokens.get(3).getTerm());
        assertEquals("you", tokens.get(4).getTerm());
        assertEquals("I", tokens.get(5).getTerm());
        assertEquals("m", tokens.get(6).getTerm());
        assertEquals("fine", tokens.get(7).getTerm());

        notifyChange = new NtTransNotifyChange(mockConfig, fid, completionFilter, watchTree);

        String result = notifyChange.toString();

        assertNotNull(result);
        // Hexdump uses uppercase letters
        // Note: completionFilter is displayed with 4 hex chars, not 8
        assertTrue(result.contains("fid=0xFFFF"));
        assertTrue(result.contains("filter=0xFFFF")); // Only 4 hex chars are shown