com.saxonica.codegen
Class NilledCompiler

java.lang.Object
  com.saxonica.codegen.ExpressionCompiler
      com.saxonica.codegen.ToBooleanCompiler
          com.saxonica.codegen.NilledCompiler

public class NilledCompiler
extends ToBooleanCompiler

Generate Java code for the nilled() function

Constructor Summary

NilledCompiler()

Method Summary

java.lang.String	compileToEffectiveBooleanValue(CompilerService compiler, Expression expr, ReturnAction result) Generate Java code to evaluate the effective boolean value of the expression
java.lang.String	compileToItem(CompilerService compiler, Expression expr) Generate Java code to evaluate the expression as an Item

Methods inherited from class com.saxonica.codegen.ToBooleanCompiler

compilePush, compileToCharSequence, compileToIterator

Methods inherited from class com.saxonica.codegen.ExpressionCompiler

compileAsLoop, compileToValueRepresentation

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

NilledCompiler

public NilledCompiler()

Method Detail

compileToEffectiveBooleanValue

public java.lang.String compileToEffectiveBooleanValue(CompilerService compiler,
                                                       Expression expr,
                                                       ReturnAction result)

Description copied from class: ExpressionCompiler

Generate Java code to evaluate the effective boolean value of the expression

Specified by:

compileToEffectiveBooleanValue in class ToBooleanCompiler

Parameters:

compiler - the compiler service

expr - the XPath expression to be compiled

result - indicates how the boolean result is to be returned

Returns:

the result depends on the supplied value of the options argument. If options is a JavaDeclaration, the code must declare a Java variable and return the name of this variable. If options is a JavaAssignment, the code must assign the value to an existing Java variable. If options is a Return, the code must generate a return statement that returns the value of the boolean (in which case the result of this method is null).

compileToItem

public java.lang.String compileToItem(CompilerService compiler,
                                      Expression expr)

Description copied from class: ExpressionCompiler

Generate Java code to evaluate the expression as an Item

Overrides:

compileToItem in class ToBooleanCompiler

Parameters:

compiler - the compiler service

expr - the expression to be compiled

Returns:

a simple Java expression (usually the name of a variable that has been declared) which will be of class Item, and which will hold the value of the expression at run-time (or hold null, representing an empty sequence).