org.geotools.filter.visitor
Class DefaultExpressionVisitor

Object
  extended by DefaultExpressionVisitor
All Implemented Interfaces:
ExpressionVisitor

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

Constructor Summary
DefaultExpressionVisitor()
           
 
Method Summary
 Object visit(Add expression, Object data)
           
 Object visit(Divide expression, Object data)
           
 Object visit(Function expression, Object data)
           
 Object visit(Literal expression, Object data)
           
 Object visit(Multiply expression, Object data)
           
 Object visit(NilExpression expression, Object data)
           
 Object visit(PropertyName expression, Object data)
           
 Object visit(Subtract expression, Object data)
           
 
Methods inherited from class Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

DefaultExpressionVisitor

public DefaultExpressionVisitor()
Method Detail

visit

public Object visit(NilExpression expression,
                    Object data)
Specified by:
visit in interface ExpressionVisitor

visit

public Object visit(Add expression,
                    Object data)
Specified by:
visit in interface ExpressionVisitor

visit

public Object visit(Divide expression,
                    Object data)
Specified by:
visit in interface ExpressionVisitor

visit

public Object visit(Function expression,
                    Object data)
Specified by:
visit in interface ExpressionVisitor

visit

public Object visit(Literal expression,
                    Object data)
Specified by:
visit in interface ExpressionVisitor

visit

public Object visit(Multiply expression,
                    Object data)
Specified by:
visit in interface ExpressionVisitor

visit

public Object visit(PropertyName expression,
                    Object data)
Specified by:
visit in interface ExpressionVisitor

visit

public Object visit(Subtract expression,
                    Object data)
Specified by:
visit in interface ExpressionVisitor


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