Files
openlayers/lib/OpenLayers/Rule/Logical.js
2008-02-08 19:51:55 +00:00

105 lines
2.8 KiB
JavaScript

/* Copyright (c) 2006-2008 MetaCarta, Inc., published under the Clear BSD
* license. See http://svn.openlayers.org/trunk/openlayers/license.txt for the
* full text of the license. */
/**
* @requires OpenLayers/Rule.js
*/
/**
* Class: OpenLayers.Rule.Logical
* This class represents ogc:And, ogc:Or and ogc:Not rules.
*
* Inherits from
* - <OpenLayers.Rule>
*/
OpenLayers.Rule.Logical = OpenLayers.Class(OpenLayers.Rule, {
/**
* APIProperty: children
* {Array(<OpenLayers.Rule>)} child rules for this rule
*/
rules: null,
/**
* APIProperty: type
* {String} type of logical operator. Available types are:
* - OpenLayers.Rule.Locical.AND = "&&";
* - OpenLayers.Rule.Logical.OR = "||";
* - OpenLayers.Rule.Logical.NOT = "!";
*/
type: null,
/**
* Constructor: OpenLayers.Rule.Logical
* Creates a logical rule (And, Or, Not).
*
* Parameters:
* options - {Object} An optional object with properties to set on the
* rule
*
* Returns:
* {<OpenLayers.Rule.Logical>}
*/
initialize: function(options) {
this.rules = [];
OpenLayers.Rule.prototype.initialize.apply(this, [options]);
},
/**
* APIMethod: destroy
* nullify references to prevent circular references and memory leaks
*/
destroy: function() {
for (var i=0; i<this.rules.length; i++) {
this.rules[i].destroy();
}
this.rules = null;
OpenLayers.Rule.prototype.destroy.apply(this, arguments);
},
/**
* APIMethod: evaluate
* evaluates this rule for a specific feature
*
* Parameters:
* feature - {<OpenLayers.Feature>} feature to apply the rule to.
*
* Returns:
* {boolean} true if the rule applies, false if it does not
*/
evaluate: function(feature) {
if (!OpenLayers.Rule.prototype.evaluate.apply(this, arguments)) {
return false;
}
switch(this.type) {
case OpenLayers.Rule.Logical.AND:
for (var i=0; i<this.rules.length; i++) {
if (this.rules[i].evaluate(feature) == false) {
return false;
}
}
return true;
case OpenLayers.Rule.Logical.OR:
for (var i=0; i<this.rules.length; i++) {
if (this.rules[i].evaluate(feature) == true) {
return true;
}
}
return false;
case OpenLayers.Rule.Logical.NOT:
return (!this.rules[0].evaluate(feature));
}
},
CLASS_NAME: "OpenLayers.Rule.Logical"
});
OpenLayers.Rule.Logical.AND = "&&";
OpenLayers.Rule.Logical.OR = "||";
OpenLayers.Rule.Logical.NOT = "!";