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Escape character

As explained in 100 Java Mistakes and How to Avoid Them

A backslash is an escape character used by Java string literals and by regular-expression syntax to alter the interpretation of the following character.

A backslash changes how Java interprets the following character. Forgetting to escape a literal backslash usually causes a compilation error, but accepted sequences can silently produce the wrong string. section 6.7

Windows paths and regular expressions

A Windows path containing sequences such as \b or \t can become a string containing a backspace or tab instead of directory text. Regular expressions add a second interpreter: Java \b means backspace, while the regular-expression engine treats it as a word boundary. Escape the backslash for the regex when necessary, and prefer Path.of(installationPath, "bin", "tar.exe") for paths. section 6.7

Avoid accidental escape sequences by applying these checks:

  • Escape a literal backslash instead of writing it directly. section 6.7
  • Inspect regex patterns at both levels: Java string parsing and regular-expression parsing. section 6.7

How 100 Java Mistakes and How to Avoid Them covers it

How deep it goes
Explains Java escaping, regex re-interpretation, accepted versus rejected sequences, and safer path construction, but not compiler internals.
Examples
Uses Windows path strings, word-boundary replacements, whitespace splitting, Path.of construction, and IntelliJ IDEA highlighting.
What it assumes
Assumes Java string-literal familiarity while defining escape sequences and distinguishing compiler interpretation from regex interpretation.
What you can do after
Apply it by escaping literal backslashes, checking both Java and regex parsing, and constructing paths with Path.of.
How it connects
Connects Java string literals with regular expressions, Windows file paths, text blocks, and IDE escape highlighting.

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This explainer was generated by Manning's knowledge graph from the text of 100 Java Mistakes and How to Avoid Them. The section links point to the parts of the book it draws on.