Package org.geotools.renderer.style

Class ExpressionExtractor

Object

ExpressionExtractor

public class ExpressionExtractor
extends Object

Helper class that allows the extraction of CQL expressions out of a plain text string using special separators. Parsing rules are:

• whatever is between ${ and } is considered a CQL expression
• $ and } can be used stand alone only escaped with \ (e.g. \$ and \})
• \ can be used stand alone only escaped with another \ (e.g. \\)

Examples of valid expressions:

• "one two three \} \$ \\" (simple literal with special chars escaped)
• "My name is ${name}" (a simple attribute reference)
• "Hi this is ${(intAtt + 2) * 10}" (cql using attribute and math expressions)

Examples of non valid expressions:

• "bla ${myAttName" (unclosed expression section)
• "bla } bla" (} is reserved, should have been escaped)

Author:

Andrea Aime - TOPP

Constructor Summary

Constructors

Constructor	Description
ExpressionExtractor()

Method Summary

Modifier and Type	Method	Description
static void	cleanExpressionCache()	Clears the CQL expression cache
static Expression	extractCqlExpressions(String expression)	Builds a CQL expression equivalent to the specified string, see class javadocs for rules on how to build the expression in string form

Methods inherited from class Object

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

Constructor Detail

ExpressionExtractor

public ExpressionExtractor()

Method Detail

extractCqlExpressions

public static Expression extractCqlExpressions(String expression)

Builds a CQL expression equivalent to the specified string, see class javadocs for rules on how to build the expression in string form

cleanExpressionCache

public static void cleanExpressionCache()

Clears the CQL expression cache