GEOS  3.4.2
GeometryExtracter.h
1 /**********************************************************************
2  *
3  * GEOS - Geometry Engine Open Source
4  * http://geos.osgeo.org
5  *
6  * Copyright (C) 2011 Sandro Santilli <strk@keybit.net>
7  * Copyright (C) 2001-2002 Vivid Solutions Inc.
8  * Copyright (C) 2006 Refractions Research Inc.
9  *
10  * This is free software; you can redistribute and/or modify it under
11  * the terms of the GNU Lesser General Public Licence as published
12  * by the Free Software Foundation.
13  * See the COPYING file for more information.
14  *
15  **********************************************************************
16  *
17  * Last port: geom/util/GeometryExtracter.java r320 (JTS-1.12)
18  *
19  **********************************************************************/
20 
21 #ifndef GEOS_GEOM_UTIL_GEOMETRYEXTRACTER_H
22 #define GEOS_GEOM_UTIL_GEOMETRYEXTRACTER_H
23 
24 #include <geos/export.h>
25 #include <geos/geom/GeometryFilter.h>
26 #include <geos/geom/GeometryCollection.h>
27 #include <geos/platform.h>
28 #include <vector>
29 
30 namespace geos {
31 namespace geom { // geos.geom
32 namespace util { // geos.geom.util
33 
37 class GEOS_DLL GeometryExtracter {
38 
39 public:
40 
48  template <class ComponentType, class TargetContainer>
49  static void extract(const Geometry& geom, TargetContainer& lst)
50  {
51  if ( const ComponentType* c = dynamic_cast<const ComponentType*>(&geom) )
52  {
53  lst.push_back(c);
54  }
55  else if ( const GeometryCollection* c =
56  dynamic_cast<const GeometryCollection*>(&geom) )
57  {
58  GeometryExtracter::Extracter<ComponentType, TargetContainer> extracter(lst);
59  c->apply_ro(&extracter);
60  }
61  }
62 
63 private:
64 
65  template <class ComponentType, class TargetContainer>
66  struct Extracter: public GeometryFilter {
67 
73  Extracter(TargetContainer& comps) : comps_(comps) {}
74 
75  TargetContainer& comps_;
76 
77  void filter_ro(const Geometry* geom)
78  {
79  if ( const ComponentType* c = dynamic_cast<const ComponentType*>(geom) ) {
80  comps_.push_back(c);
81  }
82  }
83 
84  // Declare type as noncopyable
85  Extracter(const Extracter& other);
86  Extracter& operator=(const Extracter& rhs);
87  };
88 
89  // Declare type as noncopyable
90  GeometryExtracter(const GeometryExtracter& other);
91  GeometryExtracter& operator=(const GeometryExtracter& rhs);
92 };
93 
94 } // namespace geos.geom.util
95 } // namespace geos.geom
96 } // namespace geos
97 
98 #endif
Geometry classes support the concept of applying a Geometry filter to the Geometry.
Definition: GeometryFilter.h:48
Basic implementation of Geometry, constructed and destructed by GeometryFactory.
Definition: Geometry.h:167
Represents a collection of heterogeneous Geometry objects.
Definition: GeometryCollection.h:56
Definition: GeometryExtracter.h:37
static void extract(const Geometry &geom, TargetContainer &lst)
Definition: GeometryExtracter.h:49