org.geotools.filter
Class MathExpressionImpl

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

All Implemented Interfaces:

org.opengis.filter.expression.BinaryExpression, org.opengis.filter.expression.Expression, Expression, ExpressionType, MathExpression

Direct Known Subclasses:

AddImpl, DivideImpl, MultiplyImpl, SubtractImpl

public abstract class MathExpressionImpl

extends DefaultExpression

implements MathExpression

Holds a mathematical relationship between two expressions. Note that the sub expressions must be math expressions. In other words, they must be a math literal, another math expression, or a feature attribute with a declared math type. You may create math expressions of arbitrary complexity by nesting other math expressions as sub expressions in one or more math expressions. This filter defines left and right values to clarify the sub expression precedence for non-associative operations, such as subtraction and division. For example, the left value is the numerator and the right is the denominator in an ExpressionMath division operation.

Version:

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

Author:

Rob Hranac, Vision for New York

Field Summary

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	MathExpressionImpl() No argument constructor.
protected	MathExpressionImpl(org.opengis.filter.expression.Expression e1, org.opengis.filter.expression.Expression e2)

Method Summary

void	addLeftValue(Expression leftValue) Deprecated. use setExpression1(org.opengis.filter.expression.Expression)
void	addRightValue(Expression rightValue) Deprecated. use setExpression2(org.opengis.filter.expression.Expression)
protected void	ensureOperandsSet() Convenience method which ensures that both expressions have been set.
abstract java.lang.Object	evaluate(Feature feature) Returns the value for this expression.
org.opengis.filter.expression.Expression	getExpression1() Gets the left or first expression.
org.opengis.filter.expression.Expression	getExpression2() Gets the second expression.
Expression	getLeftValue() Deprecated. use getExpression1().
Expression	getRightValue() Deprecated. use getExpression2().
short	getType() Gets the type of this expression.
protected java.lang.Object	number(double number)
void	setExpression1(org.opengis.filter.expression.Expression expression) Gets the left or first expression.
void	setExpression2(org.opengis.filter.expression.Expression expression) Gets the second expression.

Methods inherited from class org.geotools.filter.DefaultExpression

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

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

accept, eval

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

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

getValue

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

accept

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

accept, evaluate

Constructor Detail

MathExpressionImpl

protected MathExpressionImpl()

No argument constructor.

MathExpressionImpl

protected MathExpressionImpl(org.opengis.filter.expression.Expression e1,
                             org.opengis.filter.expression.Expression e2)

Method Detail

addLeftValue

public final void addLeftValue(Expression leftValue)
                        throws IllegalFilterException

Deprecated. use setExpression1(org.opengis.filter.expression.Expression)

Adds the 'left' value to this expression.

Specified by:

addLeftValue in interface MathExpression

Parameters:

leftValue - Expression to add to this expression.

Throws:

IllegalFilterException - Attempting to add non-math expression.

addRightValue

public final void addRightValue(Expression rightValue)
                         throws IllegalFilterException

Deprecated. use setExpression2(org.opengis.filter.expression.Expression)

Adds the 'right' value to this expression.

Specified by:

addRightValue in interface MathExpression

Parameters:

rightValue - Expression to add to this expression.

Throws:

IllegalFilterException - Attempting to add non-math expression.

getLeftValue

public final Expression getLeftValue()

Deprecated. use getExpression1().

Gets the left or first expression.

Specified by:

getLeftValue in interface MathExpression

Returns:

the expression on the left of the comparison.

getExpression1

public org.opengis.filter.expression.Expression getExpression1()

Gets the left or first expression.

Specified by:

getExpression1 in interface org.opengis.filter.expression.BinaryExpression

Returns:

the expression on the first side of the comparison.

setExpression1

public void setExpression1(org.opengis.filter.expression.Expression expression)

Gets the left or first expression.

Specified by:

setExpression1 in interface org.opengis.filter.expression.BinaryExpression

Returns:

the expression on the first side of the comparison.

Throws:

IllegalFilterException

getRightValue

public final Expression getRightValue()

Deprecated. use getExpression2().

Gets the right expression.

Specified by:

getRightValue in interface MathExpression

Returns:

the expression on the right of the comparison.

getExpression2

public org.opengis.filter.expression.Expression getExpression2()

Gets the second expression.

Specified by:

getExpression2 in interface org.opengis.filter.expression.BinaryExpression

Returns:

the expression on the second side of the comparison.

setExpression2

public void setExpression2(org.opengis.filter.expression.Expression expression)

Gets the second expression.

Specified by:

setExpression2 in interface org.opengis.filter.expression.BinaryExpression

Returns:

the expression on the second side of the comparison.

Throws:

IllegalFilterException

getType

public short getType()

Gets the type of this expression.

Specified by:

getType in interface MathExpression

Overrides:

getType in class DefaultExpression

Returns:

Expression type.

evaluate

public abstract java.lang.Object evaluate(Feature feature)
                                   throws java.lang.IllegalArgumentException

Returns the value for this expression.

Specified by:

evaluate in interface Expression

Overrides:

evaluate in class DefaultExpression

Parameters:

feature - Feature to use when return sub expression values.

Returns:

Value of this expression.

Throws:

java.lang.IllegalArgumentException - Feature does not match declared schema.

ensureOperandsSet

protected void ensureOperandsSet()
                          throws java.lang.IllegalArgumentException

Convenience method which ensures that both expressions have been set. If any of operands not set an exception is thrown.

Throws:

java.lang.IllegalArgumentException

number

protected java.lang.Object number(double number)