Calling External Functions

Java

To call a static function in Java:

Specify the package, class and method, then the arguments to the method.
The method must be public.
Java is picky about argument types. See below.

  (:EVAL (:JAVA (com.foo.myPackage.Humor.generateJoke ?man ?animal)))

To call a non-static function in Java:

Specify only the method name. The first argument is the object that contains the method. The rest of the arguments are passed to the method.
The method must be public
Java is picky about argument types. See below.

  (:BIND ?x (:JAVA (toString 5)))
  (:EVAL (:JAVA (getColor ?object)))

Argument type conversion between Algernon and Java

Internally, Algernon represents values using a set of classes for dynamically-typed data. When converting to Java, it picks the most appropriate class. The table below shows the mapping of internal types to external types and vice versa.

Java	Algernon
Boolean	true=T, false=NIL
Double	LispFloat
Long	LispInteger
String	All other types

LISP

Algernon contains a built-in LISP subsystem called Jatha that contains many of the standard Common LISP functions. It is useful for performing many common processing tasks.

  (:BIND ?x (:LISP (- ?value 5)))
  (:EVAL (:LISP (cons ?x ?y)))
  (:TEST (:LISP (> ?x 19)))

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