Package org.geotools.filter.visitor

Class DefaultExpressionVisitor

Object
DefaultExpressionVisitor
All Implemented Interfaces:
ExpressionVisitor
Direct Known Subclasses:
FeatureChainedAttributeVisitor
public abstract class DefaultExpressionVisitor extends Object implements ExpressionVisitor
Abstract implementation of ExpressionVisitor that simply walks the data structure.

This class implements the full ExpressionVisitor interface and will visit every Filter member of an Expression object. This class performs no actions and is not intended to be used directly, instead extend it and overide the methods for the Expression type you are interested in. Remember to call the super method if you want to ensure that the entire expression tree is still visited. 


 FilterVisitor allProperties = new DefaultExpressionVisitor(){
     public Object visit( PropertyName expr, Object data ) {
         Set set = (Set) data;
         set.addAll(expr.getPropertyName());
         return set;
     }
 };
 Set set = (Set) allProperties.accept(allFids, new HashSet());
Author:
Jody