Class StandardFunction

java.lang.Object
net.sf.saxon.functions.StandardFunction

public abstract class StandardFunction extends Object
This class contains static data tables defining the properties of standard functions. "Standard functions" here means the XPath 2.0 functions, the XSLT 2.0 functions, and a few selected extension functions which need special recognition.
  • Field Details

  • Method Details

    • register

      public static StandardFunction.Entry register(String name, Class implementationClass, int opcode, int minArguments, int maxArguments, ItemType itemType, int cardinality, int applicability)
      Register a system function in the table of function details.
      Parameters:
      name - the function name
      implementationClass - the class used to implement the function
      opcode - identifies the function when a single class implements several functions
      minArguments - the minimum number of arguments required
      maxArguments - the maximum number of arguments allowed
      itemType - the item type of the result of the function
      cardinality - the cardinality of the result of the function
      applicability - the host languages (and versions thereof) in which this function is available
      Returns:
      the entry describing the function. The entry is incomplete, it does not yet contain information about the function arguments.
    • makeEntry

      public static StandardFunction.Entry makeEntry(String name, Class implementationClass, int opcode, int minArguments, int maxArguments, ItemType itemType, int cardinality, int applicability)
      Make a table entry describing the signature of a function, with a reference to the implementation class.
      Parameters:
      name - the function name
      implementationClass - the class used to implement the function
      opcode - identifies the function when a single class implements several functions
      minArguments - the minimum number of arguments required
      maxArguments - the maximum number of arguments allowed
      itemType - the item type of the result of the function
      cardinality - the cardinality of the result of the function
      applicability - the host languages (and versions of) in which this function is available
      Returns:
      the entry describing the function. The entry is incomplete, it does not yet contain information about the function arguments.
    • arg

      public static void arg(StandardFunction.Entry e, int a, ItemType type, int cardinality, Value resultIfEmpty)
      Add information to a function entry about the argument types of the function
      Parameters:
      e - the entry for the function
      a - the position of the argument, counting from zero
      type - the item type of the argument
      cardinality - the cardinality of the argument
      resultIfEmpty - the value returned by the function if an empty sequence appears as the value of this argument, in the case when this result is unaffected by any other arguments. Supply null if this does not apply.
    • getFunction

      public static StandardFunction.Entry getFunction(String name, int arity)
      Get the table entry for the function with a given name
      Parameters:
      name - the name of the function. This may be an unprefixed local-name for functions in the system namespace, or may use the conventional prefix "saxon:" in the case of Saxon extension functions that are specially recognized
      arity - the number of arguments of the function
      Returns:
      if the function name is known, an Entry containing information about the function. Otherwise, null