Java Interop Reference 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.

PTC-Lisp emulates a subset of Java interop for LLM compatibility. These are not real JVM calls — they are BEAM-native implementations that mirror the Java API surface LLMs are trained on.

40 interop entries covering 12 Java classes in 13 presentation groups.

See also: Function Reference | PTC-Lisp Specification | Namespace coverage: docs/conformance/index.md

java.lang.Boolean

Name	Kind	Signature	Description	Notes
`Boolean/parseBoolean`	Static	`(Boolean/parseBoolean s)`	Parse "true"/"false" to boolean	Matches java.lang.Boolean.parseBoolean: nil/null and every string other than case-insensitive "true" return false; non-string, non-nil inputs raise.

java.lang.Double

Name	Kind	Signature	Description	Notes
`Double/NEGATIVE_INFINITY`	Constant	`Double/NEGATIVE_INFINITY`	Negative infinity constant (##-Inf)
`Double/NaN`	Constant	`Double/NaN`	Not-a-Number constant (##NaN)
`Double/POSITIVE_INFINITY`	Constant	`Double/POSITIVE_INFINITY`	Positive infinity constant (##Inf)
`Double/parseDouble`	Static	`(Double/parseDouble s)`	Parse string to double	Uses Java syntax, whitespace, range, rounding, and bounded NumberFormatException/NullPointerException semantics.

java.lang.Float

Name	Kind	Signature	Description	Notes
`Float/parseFloat`	Static	`(Float/parseFloat s)`	Parse string to float	Uses Java syntax, whitespace, range, direct float rounding, and bounded NumberFormatException/NullPointerException semantics.

java.lang.Integer

Name	Kind	Signature	Description	Notes
`Integer/parseInt`	Static	`(Integer/parseInt s)`	Parse string to integer	Uses Java decimal syntax, int range checks, and bounded NumberFormatException semantics.

java.lang.Long

Name	Kind	Signature	Description	Notes
`Long/parseLong`	Static	`(Long/parseLong s)`	Parse string to integer	Uses Java decimal syntax, long range checks, and bounded NumberFormatException semantics.

java.lang.Math

Name	Kind	Signature	Description	Notes
`Math/abs`	Static	`(Math/abs x)`	Return the absolute value using a selected Java primitive overload	Preserves int, long, float, or double identity and Java minimum-value overflow.
`Math/ceil`	Static	`(Math/ceil x)`	Return the smallest double value not less than the argument	Returns a Java double and preserves signed zero and non-finite values.
`Math/floor`	Static	`(Math/floor x)`	Return the largest double value not greater than the argument	Returns a Java double and preserves signed zero and non-finite values.
`Math/max`	Static	`(Math/max x y)`	Return the greater of two Java primitive values	Uses exact primitive overload selection plus Java NaN and signed-zero behavior.
`Math/min`	Static	`(Math/min x y)`	Return the smaller of two Java primitive values	Uses exact primitive overload selection plus Java NaN and signed-zero behavior.
`Math/pow`	Static	`(Math/pow base exponent)`	Return the first argument raised to the power of the second	Uses the Java double overload and its IEEE 754 special-case table.
`Math/round`	Static	`(Math/round x)`	Round a float to int or double to long with ties toward positive infinity	NaN becomes zero and infinities saturate to the selected integer primitive range.
`Math/sqrt`	Static	`(Math/sqrt x)`	Return the positive double square root	Uses Java double semantics for negative, signed-zero, NaN, and infinite inputs.

java.lang.String

Name	Kind	Signature	Description	Notes
`.contains`	Method	`(.contains s substr)`	Returns true if string contains substring
`.endsWith`	Method	`(.endsWith s suffix)`	Returns true if string ends with suffix
`.indexOf`	Method	`(.indexOf s substr), (.indexOf s substr from-index)`	Index of first occurrence of substring, or -1 if not found	Returns Java UTF-16 code-unit indexes.
`.lastIndexOf`	Method	`(.lastIndexOf s substr)`	Index of last occurrence of substring, or -1 if not found	Returns Java UTF-16 code-unit indexes.
`.length`	Method	`(.length s)`	Return the UTF-16 code-unit length of a string	Uses Java UTF-16 code units; ordinary PTC `count` remains grapheme-based.
`.startsWith`	Method	`(.startsWith s prefix)`	Returns true if string starts with prefix
`.substring`	Method	`(.substring s start), (.substring s start end)`	Extract a substring by UTF-16 code-unit index	Uses Java UTF-16 code-unit indexes. A range containing an unpaired surrogate returns invalid_java_string because PTC strings require valid UTF-8.
`.trim`	Method	`(.trim s)`	Remove leading and trailing code units from U+0000 through U+0020	Uses Java String.trim semantics, not clojure.string/trim whitespace semantics.

java.lang.System

Name	Kind	Signature	Description	Notes
`System/currentTimeMillis`	Static	`(System/currentTimeMillis)`	Return current time in milliseconds since Unix epoch

java.time.Duration

Name	Kind	Signature	Description	Notes
`.toDays`	Method	`(.toDays duration)`	Return duration length in whole days	Partial days truncate toward zero.
`.toMillis`	Method	`(.toMillis duration)`	Return duration length in milliseconds	Works on Duration values returned by `Duration/between`.
`Duration/between`	Static	`(Duration/between start-instant end-instant), (java.time.Duration/between start-instant end-instant)`	Return a native Duration between two Instants	Requires native Instant values; LocalDate, Date, and raw host temporal structs are rejected.

java.time.Instant

Name	Kind	Signature	Description	Notes
`.toEpochMilli`	Method	`(.toEpochMilli instant)`	Return epoch milliseconds from an Instant	Preserves nanoseconds natively and raises on Java long overflow.
`Instant/parse`	Static	`(Instant/parse iso-string), (java.time.Instant/parse iso-string)`	Parse strict ISO-8601 text to a native Instant	An explicit UTC or numeric offset is required; nanoseconds are retained.

java.time.LocalDate

Name	Kind	Signature	Description	Notes
`.minusDays`	Method	`(.minusDays local-date n)`	Subtract days from a LocalDate	Java long coercion is applied to `n`.
`.plusDays`	Method	`(.plusDays local-date n)`	Add days to a LocalDate	Java long coercion is applied to `n`.
`.toEpochDay`	Method	`(.toEpochDay local-date)`	Return LocalDate epoch-day integer	Works on LocalDate values returned by `LocalDate/parse`.
`LocalDate/parse`	Static	`(LocalDate/parse date-string), (java.time.LocalDate/parse date-string)`	Parse strict ISO-8601 text to a native LocalDate	Date-time text is rejected; class identity is retained natively.

java.time.LocalDate / java.time.Instant

Name	Kind	Signature	Description	Notes
`.isAfter`	Method	`(.isAfter a b)`	Returns true if receiver comes strictly after argument (same-type only)	Receiver-owned for LocalDate and Instant; mixed classes are rejected.
`.isBefore`	Method	`(.isBefore a b)`	Returns true if receiver comes strictly before argument (same-type only)	Receiver-owned for LocalDate and Instant; mixed classes are rejected.

java.util.Date

Name	Kind	Signature	Description	Notes
`.after`	Method	`(.after date other-date)`	Returns true if a legacy Date follows another	Owned only by java.util.Date.
`.before`	Method	`(.before date other-date)`	Returns true if a legacy Date precedes another	Owned only by java.util.Date.
`.getTime`	Method	`(.getTime date)`	Return exact epoch milliseconds from a legacy Date	Owned only by java.util.Date.
`java.util.Date.`	Constructor	`(java.util.Date.), (java.util.Date. epoch-milliseconds), (java.util.Date. legacy-date-string)`	Construct a native legacy Date from current time, exact milliseconds, or legacy text	Integer input is always Java epoch milliseconds. ISO-8601 strings and raw host temporal structs are not Date constructor overloads.