Precondition.BooleanPrecondition

java.lang.Object
- com.saxonica.ee.trans.Precondition
- - com.saxonica.ee.trans.Precondition.BooleanPrecondition

Enclosing class:

Precondition
```
public static class Precondition.BooleanPrecondition
extends Precondition
```
A BooleanPrecondition can in principle test any boolean characteristic of a pattern. In practice it is used to test for the existence of a named ancestor/parent element. That is, in current use the Characteristic will always be an AncestorCharacteristic

Nested Class Summary
- Nested classes/interfaces inherited from class com.saxonica.ee.trans.Precondition
  Precondition.BooleanPrecondition, Precondition.NumericComparisonPrecondition, Precondition.StringHashPrecondition

Field Summary
- Fields inherited from class com.saxonica.ee.trans.Precondition
  PRECONDITION_FALSE, PRECONDITION_TRUE, PRECONDITION_UNKNOWN

Constructor Summary

Constructors
Constructor Description

BooleanPrecondition(Characteristic characteristic)
Create a precondition that maps directly to a boolean characteristic

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`boolean`	`equals(java.lang.Object obj)`
`int`	`hashCode()`
`protected boolean`	`testPrecondition(PreconditionMatcher matcher)`	Evaluate the precondition, which will be true if and only if the value of the characteristic for the current item is the boolean value true.
`java.lang.String`	`toString()`

Methods inherited from class com.saxonica.ee.trans.Precondition
isSatisfied, setSlotNumber

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

- Constructor Detail
  - BooleanPrecondition
```
public BooleanPrecondition(Characteristic characteristic)
```
    Create a precondition that maps directly to a boolean characteristic
    
    Parameters:
    
    characteristic - the boolean characteristic
- Method Detail
  - testPrecondition
```
protected boolean testPrecondition(PreconditionMatcher matcher)
                            throws XPathException
```
    Evaluate the precondition, which will be true if and only if the value of the characteristic for the current item is the boolean value true.
    
    Specified by:
    
    testPrecondition in class Precondition
    
    Parameters:
    
    matcher - the PreconditionMatcher: holds the dynamic context for evaluation.
    
    Returns:
    
    true if the precondition is satisfied
    
    Throws:
    
    XPathException - if evaluation of the precondition fails with a dynamic error
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class java.lang.Object
  - equals
```
public boolean equals(java.lang.Object obj)
```
    Overrides:
    
    equals in class java.lang.Object
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object