org.geotools.filter
Class AttributeExpressionImpl

java.lang.Object
  org.geotools.filter.expression.ExpressionAbstract
      org.geotools.filter.DefaultExpression
          org.geotools.filter.AttributeExpressionImpl

All Implemented Interfaces:

AttributeExpression, org.opengis.filter.expression.Expression, Expression, ExpressionType, org.opengis.filter.expression.PropertyName

public class AttributeExpressionImpl

extends DefaultExpression

implements AttributeExpression

Defines a complex filter (could also be called logical filter). This filter holds one or more filters together and relates them logically in an internally defined manner.

Version:

$Id: AttributeExpressionImpl.java 18021 2006-02-14 20:36:18Z jdeolive $

Author:

Rob Hranac, TOPP

Field Summary

protected java.lang.String	attPath Holds all sub filters of this filter.
protected FeatureType	schema Holds all sub filters of this filter.

Fields inherited from class org.geotools.filter.DefaultExpression

expressionType, permissiveConstruction

Fields inherited from interface org.geotools.filter.expression.ExpressionType

ATTRIBUTE, ATTRIBUTE_DOUBLE, ATTRIBUTE_GEOMETRY, ATTRIBUTE_INTEGER, ATTRIBUTE_STRING, ATTRIBUTE_UNDECLARED, FUNCTION, LITERAL_DOUBLE, LITERAL_GEOMETRY, LITERAL_INTEGER, LITERAL_STRING, MATH_ADD, MATH_DIVIDE, MATH_MULTIPLY, MATH_SUBTRACT

Constructor Summary

protected	AttributeExpressionImpl(FeatureType schema) Constructor with the schema for this attribute.
protected	AttributeExpressionImpl(FeatureType schema, java.lang.String attPath) Constructor with schema and path to the attribute.
protected	AttributeExpressionImpl(java.lang.String xpath) Constructor with schema and path to the attribute.

Method Summary

java.lang.Object	accept(org.opengis.filter.expression.ExpressionVisitor visitor, java.lang.Object extraData) Used by FilterVisitors to perform some action on this filter instance.
boolean	equals(java.lang.Object obj) Compares this filter to the specified object.
java.lang.Object	evaluate(Feature feature) Gets the value of this attribute from the passed feature.
java.lang.String	getAttributePath() Deprecated. use getPropertyName()
java.lang.String	getPropertyName() Gets the path to the attribute to be evaluated by this expression.
int	hashCode() Override of hashCode method.
void	setAttributePath(java.lang.String attPath) Deprecated. use setPropertyName(String)
void	setPropertyName(java.lang.String attPath)
java.lang.String	toString() Return this expression as a string.

Methods inherited from class org.geotools.filter.DefaultExpression

accept, evaluate, getType, getValue, isAttributeExpression, isExpression, isGeometryExpression, isLiteralExpression, isMathExpression, isMathExpression

Methods inherited from class org.geotools.filter.expression.ExpressionAbstract

eval

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.geotools.filter.expression.AttributeExpression

getValue

Methods inherited from interface org.geotools.filter.expression.Expression

accept, getType

Methods inherited from interface org.opengis.filter.expression.Expression

evaluate

Field Detail

attPath

protected java.lang.String attPath

Holds all sub filters of this filter.

schema

protected FeatureType schema

Holds all sub filters of this filter.

Constructor Detail

AttributeExpressionImpl

protected AttributeExpressionImpl(FeatureType schema)

Constructor with the schema for this attribute.

Parameters:

schema - The schema for this attribute.

AttributeExpressionImpl

protected AttributeExpressionImpl(java.lang.String xpath)

Constructor with schema and path to the attribute.

AttributeExpressionImpl

protected AttributeExpressionImpl(FeatureType schema,
                                  java.lang.String attPath)
                           throws IllegalFilterException

Constructor with schema and path to the attribute.

Parameters:

schema - The initial (required) sub filter.

attPath - the xpath to the attribute.

Throws:

IllegalFilterException - If the attribute path is not in the schema.

Method Detail

setAttributePath

public final void setAttributePath(java.lang.String attPath)
                            throws IllegalFilterException

Deprecated. use setPropertyName(String)

Constructor with minimum dataset for a valid expression.

Specified by:

setAttributePath in interface AttributeExpression

Parameters:

attPath - The initial (required) sub filter.

Throws:

IllegalFilterException - If the attribute path is not in the schema.

getAttributePath

public final java.lang.String getAttributePath()

Deprecated. use getPropertyName()

This method calls getPropertyName().

Specified by:

getAttributePath in interface AttributeExpression

Returns:

the attribute to be queried.

getPropertyName

public java.lang.String getPropertyName()

Gets the path to the attribute to be evaluated by this expression.

Specified by:

getPropertyName in interface org.opengis.filter.expression.PropertyName

See Also:

{@link org.opengis.filter.expression.PropertyName#getPropertyName()}.

setPropertyName

public void setPropertyName(java.lang.String attPath)

Specified by:

setPropertyName in interface org.opengis.filter.expression.PropertyName

evaluate

public java.lang.Object evaluate(Feature feature)

Gets the value of this attribute from the passed feature.

Specified by:

evaluate in interface Expression

Overrides:

evaluate in class DefaultExpression

Parameters:

feature - Feature from which to extract attribute value.

Returns:

The value of this expression based on the feature.

toString

public java.lang.String toString()

Return this expression as a string.

Returns:

String representation of this attribute expression.

equals

public boolean equals(java.lang.Object obj)

Compares this filter to the specified object. Returns true if the passed in object is the same as this expression. Checks to make sure the expression types are the same as well as the attribute paths and schemas.

Parameters:

obj - - the object to compare this ExpressionAttribute against.

Returns:

true if specified object is equal to this filter; else false

hashCode

public int hashCode()

Override of hashCode method.

Returns:

a code to hash this object by.

accept

public java.lang.Object accept(org.opengis.filter.expression.ExpressionVisitor visitor,
                               java.lang.Object extraData)

Used by FilterVisitors to perform some action on this filter instance. Typicaly used by Filter decoders, but may also be used by any thing which needs infomration from filter structure. Implementations should always call: visitor.visit(this); It is importatant that this is not left to a parent class unless the parents API is identical.

Specified by:

accept in interface org.opengis.filter.expression.Expression

Overrides:

accept in class ExpressionAbstract

Parameters:

visitor - The visitor which requires access to this filter, the method must call visitor.visit(this);