com.saxonica.bytecode
Class CastableToUnionCompiler

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

public class CastableToUnionCompiler
extends ToBooleanCompiler

Generate bytecode for evaluation of a CastableToUnion

Constructor Summary

CastableToUnionCompiler()

Method Summary

void	compileToBoolean(CompilerService compiler, Expression expression) Generate bytecode to evaluate the expression as a boolean Precondition: none.
void	generateMethod(CompilerService compiler, Expression expression, org.objectweb.asm.ClassVisitor cv) This method generates the method effectiveBooleanValue, returning a boolean.

Methods inherited from class com.saxonica.bytecode.ToBooleanCompiler

compileToItem, compileToIterator, compileToPush

Methods inherited from class com.saxonica.bytecode.ExpressionCompiler

allocateStatic, compileItemFromInt, compileItemFromString, compileToLoop, compileToPrimitive, 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

CastableToUnionCompiler

public CastableToUnionCompiler()

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

generateMethod

public void generateMethod(CompilerService compiler,
                           Expression expression,
                           org.objectweb.asm.ClassVisitor cv)

This method generates the method effectiveBooleanValue, returning a boolean. The reason for doing this is the try-catch block clears the stack when we want to recover from an exception

Overrides:

generateMethod in class ExpressionCompiler