com.saxonica.codegen
Class SequenceExpressionCompiler

java.lang.Object
  extended by com.saxonica.codegen.ExpressionCompiler
      extended by com.saxonica.codegen.SequenceExpressionCompiler
Direct Known Subclasses:
AtomicSequenceConverterCompiler, AtomizerCompiler, AxisExpressionCompiler, CardinalityCheckerCompiler, CollectionCompiler, ConditionalSorterCompiler, DistinctValuesCompiler, DocumentSorterCompiler, ExtensionFunctionCallCompiler, FilterExpressionCompiler, ForEachCompiler, ForExpressionCompiler, IdCompiler, IdrefCompiler, IndexedFilterExpressionCompiler, IndexOfCompiler, InScopePrefixesCompiler, InsertCompiler, ItemCheckerCompiler, KeyFnCompiler, LazyExpressionCompiler, LetExpressionCompiler, LocalVariableReferenceCompiler, NumericPromoterCompiler, PathExpressionCompiler, RangeExpressionCompiler, RemoveCompiler, ReverseCompiler, SlashExpressionCompiler, StringToCodepointsCompiler, SubsequenceCompiler, TailCallLoopCompiler, TailExpressionCompiler, TokenizeCompiler, TupleSorterCompiler, UntypedAtomicConverterCompiler, UserFunctionCallCompiler, VariableReferenceCompiler, VennExpressionCompiler

public abstract class SequenceExpressionCompiler
extends ExpressionCompiler

Superclass for compiling expressions whose natural evaluation mode is "pull", for example, expressions that read and return existing nodes.


Constructor Summary
SequenceExpressionCompiler()
           
 
Method Summary
 void compilePush(CompilerService compiler, Expression exp)
          Generate Java code to execute the expression in push mode, that is, code to write events to the current output Receiver
 String compileToEffectiveBooleanValue(CompilerService compiler, Expression expr, ReturnAction result)
          Generate Java code to evaluate the effective boolean value of the expression
 String compileToItem(CompilerService compiler, Expression exp)
          Generate Java code to evaluate the expression as an Item
 
Methods inherited from class com.saxonica.codegen.ExpressionCompiler
compileAsLoop, compileToCharSequence, compileToIterator, compileToValueRepresentation, getConfiguration, makeExpressionCompiler, setConfiguration
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

SequenceExpressionCompiler

public SequenceExpressionCompiler()
Method Detail

compileToItem

public String compileToItem(CompilerService compiler,
                            Expression exp)
Description copied from class: ExpressionCompiler
Generate Java code to evaluate the expression as an Item

Specified by:
compileToItem in class ExpressionCompiler
Parameters:
compiler - the compiler service
exp - 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).

compileToEffectiveBooleanValue

public 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 ExpressionCompiler
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).

compilePush

public void compilePush(CompilerService compiler,
                        Expression exp)
Description copied from class: ExpressionCompiler
Generate Java code to execute the expression in push mode, that is, code to write events to the current output Receiver

Specified by:
compilePush in class ExpressionCompiler
Parameters:
compiler - the compiler service
exp - the expression to be compiled


Copyright (c) 2004-2010 Saxonica Limited. All rights reserved.