com.saxonica.bytecode
Class GeneralComparisonCompiler

java.lang.Object
  com.saxonica.bytecode.ExpressionCompiler
      com.saxonica.bytecode.ToBooleanCompiler
          com.saxonica.bytecode.GeneralComparisonCompiler

public class GeneralComparisonCompiler
extends ToBooleanCompiler

Generate code for a GeneralComparison

Constructor Summary

GeneralComparisonCompiler()

Method Summary

void	compileToBoolean(CompilerService compiler, Expression expression) Generate bytecode to evaluate the expression as a boolean Precondition: none.
void	compileToBooleanManyToMany(CompilerService compiler, GeneralComparison comparison)
static void	generateComparisonCode(CompilerService compiler, ComparisonExpression comparison, LabelInfo returnTrue, LabelInfo returnFalse, LabelInfo end, int item0Var, int item1Var, AtomicType type0, AtomicType type1, boolean checkTypes) Generate code to compare two items, leaving a boolean result on the top of the bytecode stack

Methods inherited from class com.saxonica.bytecode.ToBooleanCompiler

compileToItem, compileToIterator, compileToPush

Methods inherited from class com.saxonica.bytecode.ExpressionCompiler

allocateStatic, compileItemFromInt, compileItemFromString, compileToLoop, compileToPrimitive, generateMethod, getConfiguration, handleEmptyStringResult, setConfiguration, throwXPathException, throwXPathException, unboxItem, verify, visitAnnotation, visitLineNumber

Methods inherited from class java.lang.Object

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

Constructor Detail

GeneralComparisonCompiler

public GeneralComparisonCompiler()

Method Detail

compileToBoolean

public void compileToBoolean(CompilerService compiler,
                             Expression expression)
                      throws CannotCompileException

Description copied from class: ExpressionCompiler

Generate bytecode to evaluate the expression as a boolean Precondition: none. Postcondition: at execution time, the stack contains an integer (0=false, 1=true) representing the result of the expression

Specified by:

compileToBoolean in class ExpressionCompiler

Parameters:

compiler - the compiler service

expression - the expression to be compiled

Throws:

CannotCompileException

compileToBooleanManyToMany

public void compileToBooleanManyToMany(CompilerService compiler,
                                       GeneralComparison comparison)
                                throws CannotCompileException

Throws:

CannotCompileException

generateComparisonCode

public static void generateComparisonCode(CompilerService compiler,
                                          ComparisonExpression comparison,
                                          LabelInfo returnTrue,
                                          LabelInfo returnFalse,
                                          LabelInfo end,
                                          int item0Var,
                                          int item1Var,
                                          AtomicType type0,
                                          AtomicType type1,
                                          boolean checkTypes)

Generate code to compare two items, leaving a boolean result on the top of the bytecode stack

Parameters:

compiler - the compiler service

comparison - the comparison expression being compiled

returnTrue - label to jump to to return true

returnFalse - label to jump to to return false

end - label to jump to to exit, with the result on stack

item0Var - position of local variable (or if negative, argument) holding the first item

item1Var - position of local variable (or if negative, argument) holding the second item

type0 - static type of the first item

type1 - static type of the second item

checkTypes - if true, code needs to be generated to check the items are comparable