# Java String Audit for PTC-Lisp > **Warning:** This file is auto-generated by `mix ptc.gen_docs` from `priv/java_interop.exs`. > Manual edits will be overwritten. Edit `priv/java_interop.exs` instead. Curated LLM-compatibility target for `java.lang.String` methods. See also: [Function Reference](../function-reference.md) | [Namespace Coverage](index.md) | [Clojure Core Audit](clojure-core-audit.md) | [Clojure String Audit](clojure-string-audit.md) | [Clojure Set Audit](clojure-set-audit.md) | [Clojure Walk Audit](clojure-walk-audit.md) | [Java Math Audit](java-math-audit.md) | [Java Boolean Audit](java-lang-boolean-audit.md) | [Java Double Audit](java-lang-double-audit.md) | [Java Float Audit](java-lang-float-audit.md) | [Java Integer Audit](java-lang-integer-audit.md) | [Java Long Audit](java-lang-long-audit.md) | [Java System Audit](java-lang-system-audit.md) | [Java LocalDate Audit](java-time-local-date-audit.md) | [Java Instant Audit](java-time-instant-audit.md) | [Java Duration Audit](java-time-duration-audit.md) | [Java Period Audit](java-time-period-audit.md) | [Java Date Audit](java-util-date-audit.md) ## Summary Coverage excludes `not_relevant` entries: `supported / (supported + candidate + not_classified)`. | Status | Count | |--------|-------| | Supported | 8 | | Candidate | 5 | | Not Relevant | 2 | | Not Classified | 0 | | Relevant Target | 13 | | Coverage | 8/13 (61.5%) | | **Total** | **15** | ## Details | Var | Status | Description | Notes | |-----|--------|-------------|-------| | `.charAt` | 🔲 candidate | Return character at index | Potentially useful, but PTC-Lisp must define how a Java UTF-16 char, including an isolated surrogate, is represented. | | `.contains` | ✅ supported | Substring containment | DIV-40: character literals are accepted as arguments (PTC-Lisp has no Character type). DIV-41: character-literal receivers behave as one-character strings. DIV-53: the bounded UTF-16 view rejects String inputs larger than 256,000 bytes. | | `.endsWith` | ✅ supported | Suffix test | DIV-40: character literals are accepted as arguments (PTC-Lisp has no Character type). DIV-41: character-literal receivers behave as one-character strings. DIV-53: the bounded UTF-16 view rejects String inputs larger than 256,000 bytes. | | `.equalsIgnoreCase` | 🔲 candidate | Case-insensitive string equality | Common Java idiom in generated code. | | `.getBytes` | ❌ not_relevant | Encode string to bytes | Byte arrays and charsets are outside the sandbox data model. | | `.indexOf` | ✅ supported | First substring index | BUG GAP-J05: integer character-code overloads are unsupported. Indexes use Java UTF-16 code units. DIV-41: character-literal receivers behave as one-character strings (PTC-Lisp has no Character type). DIV-53: the bounded UTF-16 view rejects String inputs larger than 256,000 bytes. | | `.intern` | ❌ not_relevant | Intern a Java string | JVM string pool operation; not meaningful on BEAM. | | `.isEmpty` | 🔲 candidate | Return true for empty string | empty? covers the common PTC-Lisp need. | | `.lastIndexOf` | ✅ supported | Last substring index | BUG GAP-J05: substring/from-index and integer character-code overloads are unsupported. Indexes use Java UTF-16 code units. DIV-41: character-literal receivers behave as one-character strings (PTC-Lisp has no Character type). DIV-53: the bounded UTF-16 view rejects String inputs larger than 256,000 bytes. | | `.length` | ✅ supported | String length | Returns Java UTF-16 code-unit length. DIV-41: character-literal receivers behave as one-character strings (PTC-Lisp has no Character type). DIV-53: the bounded UTF-16 view rejects String inputs larger than 256,000 bytes. | | `.startsWith` | ✅ supported | Prefix test | BUG GAP-J05: prefix/offset overload is unsupported. DIV-40: character literals are accepted as arguments (PTC-Lisp has no Character type). DIV-41: character-literal receivers behave as one-character strings. DIV-53: the bounded UTF-16 view rejects String inputs larger than 256,000 bytes. | | `.substring` | ✅ supported | Extract substring | Uses Java UTF-16 code-unit indexes. DIV-41: character-literal receivers behave as one-character strings. DIV-53: ranges containing an unpaired surrogate and inputs larger than 256,000 bytes produce invalid_java_string. | | `.toLowerCase` | 🔲 candidate | Lowercase string | Deferred until a deterministic locale and pinned Unicode-data contract are selected. | | `.toUpperCase` | 🔲 candidate | Uppercase string | Deferred until a deterministic locale and pinned Unicode-data contract are selected. | | `.trim` | ✅ supported | Remove leading and trailing code units from U+0000 through U+0020 | Uses Java String.trim semantics, which differ from clojure.string/trim. DIV-41: character-literal receivers behave as one-character strings. DIV-53: String inputs larger than 256,000 bytes produce invalid_java_string. |