org.exist.xpath
Class BinaryOp
java.lang.Object
org.exist.xpath.PathExpr
org.exist.xpath.BinaryOp
- All Implemented Interfaces:
- Expression
- Direct Known Subclasses:
- OpAnd, OpEquals, OpNumeric, OpOr
- public abstract class BinaryOp
- extends PathExpr
Methods inherited from class org.exist.xpath.PathExpr |
add, add, addDocument, addPath, addPredicate, getDocumentSet, getExpression, getLength, preselect, setDocumentSet, setFirstExpression, setInPredicate |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
BinaryOp
public BinaryOp(BrokerPool pool)
returnsType
public int returnsType()
- Description copied from interface:
Expression
- The type of value, this expression returns.
Depending on the type of expression, this method should
return one of the constants defined in class Constants, e.g.
TYPE_NODELIST, TYPE_STRING, TYPE_NUM, TYPE_BOOL.
- Specified by:
returnsType
in interface Expression
- Overrides:
returnsType
in class PathExpr
getLeft
public Expression getLeft()
getRight
public Expression getRight()
preselect
public abstract DocumentSet preselect(DocumentSet in_docs)
- Description copied from interface:
Expression
- Determine the documents, taken from in_docs, for which this expression
will possibly yield a result. An expression does not have to do
anything here. It may simply return in_docs.
This method is used to restrict the range of documents in question for
a given xpath-expression. It is called before the xpath-expression is
actually executed.
- Specified by:
preselect
in interface Expression
- Overrides:
preselect
in class PathExpr
eval
public abstract Value eval(DocumentSet docs,
NodeSet context,
NodeProxy node)
- Description copied from interface:
Expression
- Evaluate the expression represented by this object.
Depending on the context in which this expression is executed,
either context, node or both of them may be set. An implementing
class should know how to handle this. Most classes only expect
context to contain a list of nodes which represents the current
context of this expression.
- Specified by:
eval
in interface Expression
- Overrides:
eval
in class PathExpr
pprint
public abstract java.lang.String pprint()
- Description copied from interface:
Expression
- Return a readable representation of this expression.
This method is called whenever the xpath-query should be
displayed to the user.
- Specified by:
pprint
in interface Expression
- Overrides:
pprint
in class PathExpr
Copyright (C) Wolfgang Meier. All rights reserved.