ol.Filter is now a (base) class, not an interface any more

ol.Filter can now also be used to provide a simple filter that
just evaluates a user provided filter function against a
feature.

src/ol/filter/extentfilter.js

@@ -7,10 +7,11 @@ goog.require('ol.filter.Filter');
 
 /**
  * @constructor
- * @implements {ol.filter.Filter}
+ * @extends {ol.filter.Filter}
  * @param {ol.Extent} extent The extent.
  */
 ol.filter.Extent = function(extent) {
+  goog.base(this);
 
   /**
    * @type {ol.Extent}
@@ -19,6 +20,7 @@ ol.filter.Extent = function(extent) {
   this.extent_ = extent;
 
 };
+goog.inherits(ol.filter.Extent, ol.filter.Filter);
 
 
 /**

src/ol/filter/filter.js

@@ -5,13 +5,20 @@ goog.require('ol.Feature');
 
 
 /**
- * @interface
+ * @constructor
+ * @param {function(this:ol.filter.Filter, ol.Feature)=} opt_filterFunction
+ *     Filter function. Should return true if the passed feature passes the
+ *     filter, false otherwise.
  */
-ol.filter.Filter = function() {};
+ol.filter.Filter = function(opt_filterFunction) {
+  if (goog.isDef(opt_filterFunction)) {
+    this.applies = opt_filterFunction;
+  }
+};
 
 
 /**
- * @param {ol.Feature} feature Feature to evaluate.
+ * @param {ol.Feature} feature Feature to evaluate the filter against.
  * @return {boolean} The provided feature passes this filter.
  */
-ol.filter.Filter.prototype.applies = function(feature) {};
+ol.filter.Filter.prototype.applies = goog.abstractMethod;

src/ol/filter/geometryfilter.js

@@ -8,10 +8,11 @@ goog.require('ol.geom.GeometryType');
 
 /**
  * @constructor
- * @implements {ol.filter.Filter}
+ * @extends {ol.filter.Filter}
  * @param {ol.geom.GeometryType} type The geometry type.
  */
 ol.filter.Geometry = function(type) {
+  goog.base(this);
 
   /**
    * @type {ol.geom.GeometryType}
@@ -20,6 +21,7 @@ ol.filter.Geometry = function(type) {
   this.type_ = type;
 
 };
+goog.inherits(ol.filter.Geometry, ol.filter.Filter);
 
 
 /**

src/ol/filter/logicalfilter.js

@@ -7,11 +7,12 @@ goog.require('ol.filter.Filter');
 
 /**
  * @constructor
- * @implements {ol.filter.Filter}
+ * @extends {ol.filter.Filter}
  * @param {Array.<ol.filter.Filter>} filters Filters to and-combine.
  * @param {!ol.filter.LogicalOperator} operator Operator.
  */
 ol.filter.Logical = function(filters, operator) {
+  goog.base(this);
 
   /**
    * @type {Array.<ol.filter.Filter>}
@@ -25,6 +26,7 @@ ol.filter.Logical = function(filters, operator) {
   this.operator = operator;
 
 };
+goog.inherits(ol.filter.Logical, ol.filter.Filter);
 
 
 /**