org.geotools.expr
Class AbstractMathExpr

java.lang.Object
  org.geotools.expr.AbstractExpr
      org.geotools.expr.AbstractMathExpr

All Implemented Interfaces:

Expr, MathExpr

Direct Known Subclasses:

AttributeMathExpr, LiteralMathExpr

public class AbstractMathExpr

extends org.geotools.expr.AbstractExpr

implements MathExpr

Author:

Jody Garnett TODO To change the template for this generated type comment go to Window - Preferences - Java - Code Style - Code Templates

Field Summary

protected FilterFactory

factory

Constructor Summary

AbstractMathExpr()

Method Summary

MathExpr	add(double number)
MathExpr	add(MathExpr expr)
MathExpr	add(java.lang.Number number)
Expr	and(Expr expr) Explicit Expr chain extention - required for custom Expressions.
Expr	bbox(com.vividsolutions.jts.geom.Envelope bbox) Convience method for: geom().disjoint( geom( bbox )).not()
Expr	between(double min, double max)
Expr	between(Expr min, Expr max) min <= expr <= max
Expr	between(java.lang.Number min, java.lang.Number max)
MathExpr	divide(double number)
MathExpr	divide(MathExpr expr)
MathExpr	divide(java.lang.Number number)
Expr	eq(double number)
Expr	eq(Expr expr) expr == expr
Expr	eq(java.lang.Number number)
Expr	eval() Evaludate Expr - with LiteralExpr as a goal.
Expression	expression(FeatureType schema) Turns a Filter into an a logical true/false expression.
Expr	fid(java.util.Set fids) expr.filter( fids ) Restruct current Expr to provided featureId(s).
Expr	fid(java.lang.String featureID) Convience method for accessing a single fid
Filter	filter(FeatureType schema) Useful super class that casts expressions into a Filter.
Expr	fn(java.lang.String name) name( expr )
Expr	fn(java.lang.String name, Expr expr) name( expr, expr )
Expr	fn(java.lang.String name, Expr[] expr) name( expr[0], expr[0], ... )
Expr	gt(double number)
Expr	gt(Expr expr) expr > expr
Expr	gt(java.lang.Number number)
Expr	gte(double number)
Expr	gte(Expr expr) expr >= expr
Expr	gte(java.lang.Number number)
Expr	lt(double number)
Expr	lt(Expr expr) expr < expr
Expr	lt(java.lang.Number number)
Expr	lte(double number)
Expr	lte(Expr expr) expr <= expr
Expr	lte(java.lang.Number number)
MathExpr	multiply(double number)
MathExpr	multiply(MathExpr expr)
MathExpr	multiply(java.lang.Number number)
Expr	ne(double number)
Expr	ne(Expr expr) expr !
Expr	ne(java.lang.Number number)
Expr	not() !
Expr	notNull() expr !
Expr	or(Expr expr) Expr Disjunction
Expr	reduce(java.lang.String bind) Reduce attributes matching "bind/x" to "x".
Expr	resolve(org.opengis.catalog.MetadataEntity metadata) Bind all meta entries according to provided metadata.
Expr	resolve(java.lang.String bind, Feature feature) Bind attributes matching "bind/x" to feature.getAttribute("x").
MathExpr	subtract(double number)
MathExpr	subtract(MathExpr expr)
MathExpr	subtract(java.lang.Number number)

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.geotools.expr.Expr

and, bbox, between, eq, eval, expression, fid, fid, filter, fn, fn, fn, gt, gte, lt, lte, ne, not, notNull, or, reduce, resolve, resolve

Field Detail

factory

protected FilterFactory factory

Constructor Detail

AbstractMathExpr

public AbstractMathExpr()

Method Detail

add

public MathExpr add(MathExpr expr)

Specified by:

add in interface MathExpr

add

public MathExpr add(java.lang.Number number)

Specified by:

add in interface MathExpr

add

public MathExpr add(double number)

Specified by:

add in interface MathExpr

subtract

public MathExpr subtract(MathExpr expr)

Specified by:

subtract in interface MathExpr

subtract

public MathExpr subtract(java.lang.Number number)

Specified by:

subtract in interface MathExpr

subtract

public MathExpr subtract(double number)

Specified by:

subtract in interface MathExpr

divide

public MathExpr divide(MathExpr expr)

Specified by:

divide in interface MathExpr

divide

public MathExpr divide(java.lang.Number number)

Specified by:

divide in interface MathExpr

divide

public MathExpr divide(double number)

Specified by:

divide in interface MathExpr

multiply

public MathExpr multiply(MathExpr expr)

Specified by:

multiply in interface MathExpr

multiply

public MathExpr multiply(java.lang.Number number)

Specified by:

multiply in interface MathExpr

multiply

public MathExpr multiply(double number)

Specified by:

multiply in interface MathExpr

eq

public Expr eq(java.lang.Number number)

Specified by:

eq in interface MathExpr

eq

public Expr eq(double number)

Specified by:

eq in interface MathExpr

gt

public Expr gt(java.lang.Number number)

Specified by:

gt in interface MathExpr

gt

public Expr gt(double number)

Specified by:

gt in interface MathExpr

gte

public Expr gte(java.lang.Number number)

Specified by:

gte in interface MathExpr

gte

public Expr gte(double number)

Specified by:

gte in interface MathExpr

lt

public Expr lt(java.lang.Number number)

Specified by:

lt in interface MathExpr

lt

public Expr lt(double number)

Specified by:

lt in interface MathExpr

lte

public Expr lte(java.lang.Number number)

Specified by:

lte in interface MathExpr

lte

public Expr lte(double number)

Specified by:

lte in interface MathExpr

ne

public Expr ne(java.lang.Number number)

Specified by:

ne in interface MathExpr

ne

public Expr ne(double number)

Specified by:

ne in interface MathExpr

between

public Expr between(java.lang.Number min,
                    java.lang.Number max)

Specified by:

between in interface MathExpr

between

public Expr between(double min,
                    double max)

Specified by:

between in interface MathExpr

eval

public Expr eval()

Evaludate Expr - with LiteralExpr as a goal.

By default this method simply returns the current Expr.

Specified by:

eval in interface Expr

resolve

public Expr resolve(org.opengis.catalog.MetadataEntity metadata)

Bind all meta entries according to provided metadata.

 Feature
 

Specified by:

resolve in interface Expr

Parameters:

metadata -

Returns:

Expr with all meta( xpath ) Exprs resolved

reduce

public Expr reduce(java.lang.String bind)

Reduce attributes matching "bind/x" to "x".

This may be used to reduce an Expr as part of an otter join, to something simple that can be passed off to an DataStore by way of filter( FeatureType ).

Example:

 FeatureType RIVER = river.getSchema();
 FeatureType HAZZARD = hazard.getSchema();
 
 Expr joinExpr = Exprs.attribute("river/name").eq( Exprs.attribute("hazzard/river") );
 
 FeatureReader outer = river.getFeatures().reader();
 while( reader.hasNext() ){
   Feature aRiver = outer.next();
 
   Expr inner = joinExpr.resolve( "river", aRiver ).reduce( "hazzard" );
   FeatureReader inner = district.getFeatures( inner.filter( HAZZARD ) );
 	 while( inner.hasNext() ){
      Feature aHazzard = inner.next();
 
 		// code here has access to both aRiver and aHazzard 
   } 
   inner.close();
 }
 outer.close();
 

Specified by:

reduce in interface Expr

resolve

public Expr resolve(java.lang.String bind,
                    Feature feature)

Bind attributes matching "bind/x" to feature.getAttribute("x").

This may be used to reduce an Expr as part of an otter join, to something simple that can be passed off to an DataStore by way of filter( FeatureType ).

Specified by:

resolve in interface Expr

Parameters:

bind -

feature -

Returns:

filter

public Filter filter(FeatureType schema)
              throws java.io.IOException

Useful super class that casts expressions into a Filter.

To turn Expression into a Filter I am going to follow the usual Perl defaults of "true".

• Boolean.TRUE is true
• Non empty String is true
• Non zero is true
• Non zero length array is true
• Non isEmpty Collection/Map is true
• Non isNull Envelope is true

Where true means that the generated Filter will accept the results.

Specified by:

filter in interface Expr

Throws:

java.io.IOException

expression

public Expression expression(FeatureType schema)
                      throws java.io.IOException

Turns a Filter into an a logical true/false expression.

Specified by:

expression in interface Expr

Throws:

java.io.IOException

bbox

public Expr bbox(com.vividsolutions.jts.geom.Envelope bbox)

Convience method for: geom().disjoint( geom( bbox )).not()

Specified by:

bbox in interface Expr

fid

public Expr fid(java.lang.String featureID)

Convience method for accessing a single fid

Specified by:

fid in interface Expr

Returns:

fid

public Expr fid(java.util.Set fids)

Description copied from interface: Expr

expr.filter( fids )

Restruct current Expr to provided featureId(s).

Specified by:

fid in interface Expr

not

public Expr not()

Description copied from interface: Expr

!expr

Invert of logical TRUTH value. Can be used to test for non contained fitler contents or FALSE Expressions

Specified by:

not in interface Expr

Returns:

Invert of Logical TRUETH value

and

public Expr and(Expr expr)

Description copied from interface: Expr

Explicit Expr chain extention - required for custom Expressions.

Specified by:

and in interface Expr

Parameters:

expr -

Returns:

Explicit chain extention.

or

public Expr or(Expr expr)

Description copied from interface: Expr

Expr Disjunction

Specified by:

or in interface Expr

eq

public Expr eq(Expr expr)

Description copied from interface: Expr

expr == expr

Specified by:

eq in interface Expr

gt

public Expr gt(Expr expr)

Description copied from interface: Expr

expr > expr

Specified by:

gt in interface Expr

gte

public Expr gte(Expr expr)

Description copied from interface: Expr

expr >= expr

Specified by:

gte in interface Expr

lt

public Expr lt(Expr expr)

Description copied from interface: Expr

expr < expr

Specified by:

lt in interface Expr

lte

public Expr lte(Expr expr)

Description copied from interface: Expr

expr <= expr

Specified by:

lte in interface Expr

ne

public Expr ne(Expr expr)

Description copied from interface: Expr

expr != expr

Specified by:

ne in interface Expr

between

public Expr between(Expr min,
                    Expr max)

Description copied from interface: Expr

min <= expr <= max

Specified by:

between in interface Expr

notNull

public Expr notNull()

Description copied from interface: Expr

expr != null

Specified by:

notNull in interface Expr

fn

public Expr fn(java.lang.String name)

Description copied from interface: Expr

name( expr )

Specified by:

fn in interface Expr

fn

public Expr fn(java.lang.String name,
               Expr expr)

Description copied from interface: Expr

name( expr, expr )

Specified by:

fn in interface Expr

fn

public Expr fn(java.lang.String name,
               Expr[] expr)

Description copied from interface: Expr

name( expr[0], expr[0], ... )

Specified by:

fn in interface Expr