requiredVersion

ScriptBasic for Java Interface Versions

ScriptBasic provides an interface for functions implemented in Java and callable from BASIC. The functions implemented in Java do not need to implement any Java interface. In this terminology the "interface" ScriptBasic provides is not a Java interface. This term refers to the way ScriptBasic calls these methods.

As ScriptBasic develops the way how ScriptBasic handles these extension functions also develops and some new features become available. If an extension relies on such an advanced feature it will not work with earlier versions of ScriptBasic that implements an earlier version of the interface. Therefore ScriptBasic introduces a simple long number that specifies the version of the interface.

This document describes the differences between the different interface versions.

• 1L

This is the initial version.

• 2L

ScriptBasic 1.0.4 introduced the possibility for an extension to accept BASIC array as argument and also to return an array as value. If you need that feature you have to specify requiredVersion=2L in the annotation of the static method implementing the extension function.

For example the method length() implemented in the class UtilityFunctions as

     @BasicFunction(classification = Utility.class, requiredVersion = 2L)
     public static Long length(Object arg) {
         if (arg == null) {
             return null;
         } else if (arg instanceof BasicArrayValue) {
             BasicArrayValue array = (BasicArrayValue) arg;
             return array.getLength();
         } else if (arg instanceof String) {
             String string = (String) arg;
             return (long) string.length();
         } else if (arg.getClass().isArray()) {
             return (long) Array.getLength(arg);
         }
         return null;
     }

This is because this basic function would not work with versions of ScriptBasic prior to 1.0.4

• 3L

  ScriptBasic can call methods that accept an Interpreter as first argument.