GeneralComparison10

java.lang.Object
- net.sf.saxon.expr.Expression
- - net.sf.saxon.expr.BinaryExpression
  - - net.sf.saxon.expr.GeneralComparison10

All Implemented Interfaces:

java.io.Serializable, javax.xml.transform.SourceLocator, LocationProvider, SaxonLocator, EvaluableItem, SequenceIterable, InstructionInfo, org.xml.sax.Locator
```
public class GeneralComparison10
extends BinaryExpression
```
GeneralComparison10: a boolean expression that compares two expressions for equals, not-equals, greater-than or less-than. This implements the operators =, !=, <, >, etc. This version of the class implements general comparisons in XPath 1.0 backwards compatibility mode, as defined in the Oct 2004 revision of the specifications.

See Also:

Serialized Form

Field Summary

Fields
Modifier and Type Field Description

protected AtomicComparer comparer

protected int singletonOperator
- Fields inherited from class net.sf.saxon.expr.BinaryExpression
  operand0, operand1, operator
- Fields inherited from class net.sf.saxon.expr.Expression
  EVALUATE_METHOD, ITERATE_METHOD, locationId, PROCESS_METHOD, staticProperties

Fields
Modifier and Type	Field	Description
`protected AtomicComparer`	`comparer`
`protected int`	`singletonOperator`

Constructor Summary

Constructors
Constructor	Description
`GeneralComparison10(Expression p0, int op, Expression p1)`	Create a general comparison identifying the two operands and the operator

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`int`	`computeCardinality()`	Determine the static cardinality.
`Expression`	`copy()`	Copy an expression.
`protected java.lang.String`	`displayOperator()`
`boolean`	`effectiveBooleanValue(XPathContext context)`	Evaluate the expression in a boolean context
`Item`	`evaluateItem(XPathContext context)`	Evaluate the expression in a given context
`ItemType`	`getItemType(TypeHierarchy th)`	Determine the data type of the expression
`Expression`	`optimize(ExpressionVisitor visitor, ItemType contextItemType)`	Optimize the expression
`Expression`	`typeCheck(ExpressionVisitor visitor, ItemType contextItemType)`	Type-check the expression

Methods inherited from class net.sf.saxon.expr.BinaryExpression
computeSpecialProperties, equals, explain, getOperands, getOperator, hashCode, isAssociative, isCommutative, isInverse, iterateSubExpressions, promote, replaceSubExpression, setFlattened, simplify, toString

Methods inherited from class net.sf.saxon.expr.Expression
addToPathMap, adoptChildExpression, checkForUpdatingSubexpressions, checkPermittedContents, computeDependencies, computeStaticProperties, display, doPromotion, dynamicError, evaluateAsString, evaluatePendingUpdates, explain, findParentOf, getCardinality, getColumnNumber, getColumnNumber, getConstructType, getContainer, getDependencies, getExecutable, getHostLanguage, getImplementationMethod, getIntrinsicDependencies, getLineNumber, getLineNumber, getLocationId, getLocationProvider, getObjectName, getProperties, getProperty, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, getSystemId, hasLoopingSubexpression, implementsStaticTypeCheck, isUpdatingExpression, iterate, iterateEvents, markTailFunctionCalls, process, resetLocalStaticProperties, setContainer, setFiltered, setLocationId, staticTypeCheck, suppressValidation, typeError

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Field Detail
  - singletonOperator
```
protected int singletonOperator
```
  - comparer
```
protected AtomicComparer comparer
```
- Constructor Detail
  - GeneralComparison10
```
public GeneralComparison10(Expression p0,
                           int op,
                           Expression p1)
```
    Create a general comparison identifying the two operands and the operator
    
    Parameters:
    
    p0 - the left-hand operand
    
    op - the operator, as a token returned by the Tokenizer (e.g. Token.LT)
    
    p1 - the right-hand operand
- Method Detail
  - computeCardinality
```
public int computeCardinality()
```
    Determine the static cardinality. Returns [1..1]
    
    Overrides:
    
    computeCardinality in class BinaryExpression
    
    Returns:
    
    the computed cardinality, as one of the values StaticProperty.ALLOWS_ZERO_OR_ONE, StaticProperty.EXACTLY_ONE, StaticProperty.ALLOWS_ONE_OR_MORE, StaticProperty.ALLOWS_ZERO_OR_MORE
  - typeCheck
```
public Expression typeCheck(ExpressionVisitor visitor,
                            ItemType contextItemType)
                     throws XPathException
```
    Type-check the expression
    
    Overrides:
    
    typeCheck in class BinaryExpression
    
    Parameters:
    
    visitor - an expression visitor
    
    contextItemType - the static type of "." at the point where this expression is invoked. The parameter is set to null if it is known statically that the context item will be undefined. If the type of the context item is not known statically, the argument is set to Type.ITEM_TYPE
    
    Returns:
    
    the checked expression
    
    Throws:
    
    XPathException - if an error is discovered during this phase (typically a type error)
  - optimize
```
public Expression optimize(ExpressionVisitor visitor,
                           ItemType contextItemType)
                    throws XPathException
```
    Optimize the expression
    
    Overrides:
    
    optimize in class BinaryExpression
    
    Parameters:
    
    visitor - an expression visitor
    
    contextItemType - the static type of "." at the point where this expression is invoked. The parameter is set to null if it is known statically that the context item will be undefined. If the type of the context item is not known statically, the argument is set to Type.ITEM_TYPE
    
    Returns:
    
    the checked expression
    
    Throws:
    
    XPathException - if an error is discovered during this phase (typically a type error)
  - evaluateItem
```
public Item evaluateItem(XPathContext context)
                  throws XPathException
```
    Evaluate the expression in a given context
    
    Specified by:
    
    evaluateItem in interface EvaluableItem
    
    Overrides:
    
    evaluateItem in class Expression
    
    Parameters:
    
    context - the given context for evaluation
    
    Returns:
    
    a BooleanValue representing the result of the numeric comparison of the two operands
    
    Throws:
    
    XPathException - if any dynamic error occurs evaluating the expression
  - effectiveBooleanValue
```
public boolean effectiveBooleanValue(XPathContext context)
                              throws XPathException
```
    Evaluate the expression in a boolean context
    
    Overrides:
    
    effectiveBooleanValue in class Expression
    
    Parameters:
    
    context - the given context for evaluation
    
    Returns:
    
    a boolean representing the result of the numeric comparison of the two operands
    
    Throws:
    
    XPathException - if any dynamic error occurs evaluating the expression
  - copy
```
public Expression copy()
```
    Copy an expression. This makes a deep copy.
    
    Specified by:
    
    copy in class Expression
    
    Returns:
    
    the copy of the original expression
  - getItemType
```
public ItemType getItemType(TypeHierarchy th)
```
    Determine the data type of the expression
    
    Specified by:
    
    getItemType in class Expression
    
    Parameters:
    
    th - the type hierarchy cache
    
    Returns:
    
    Type.BOOLEAN
  - displayOperator
```
protected java.lang.String displayOperator()
```
    Overrides:
    
    displayOperator in class BinaryExpression

Class GeneralComparison10

Field Summary

Fields inherited from class net.sf.saxon.expr.BinaryExpression

Fields inherited from class net.sf.saxon.expr.Expression

Constructor Summary

Method Summary

Methods inherited from class net.sf.saxon.expr.BinaryExpression

Methods inherited from class net.sf.saxon.expr.Expression

Methods inherited from class java.lang.Object

Field Detail

singletonOperator

comparer

Constructor Detail

GeneralComparison10

Method Detail

computeCardinality

typeCheck

optimize

evaluateItem

effectiveBooleanValue

copy

getItemType

displayOperator