diff --git a/modules/mol/base/src/CMakeLists.txt b/modules/mol/base/src/CMakeLists.txt
index 8bb7187ebe9d229fe4aad338a71e53674e22ae3f..8d206d3c61b193deb48942e563baadb31c4c5aa4 100644
--- a/modules/mol/base/src/CMakeLists.txt
+++ b/modules/mol/base/src/CMakeLists.txt
@@ -83,6 +83,7 @@ sec_structure.hh
spatial_organizer.hh
surface.hh
surface_builder.hh
+builder.hh
surface_handle.hh
surface_prop.hh
torsion_handle.hh
diff --git a/modules/mol/base/src/builder.hh b/modules/mol/base/src/builder.hh
new file mode 100644
index 0000000000000000000000000000000000000000..0a652a8b010ac97182a50e79591c00f6c3c6b81d
--- /dev/null
+++ b/modules/mol/base/src/builder.hh
@@ -0,0 +1,77 @@
+
+//------------------------------------------------------------------------------
+// This file is part of the OpenStructure project <www.openstructure.org>
+//
+// Copyright (C) 2008-2011 by the OpenStructure authors
+//
+// This library is free software; you can redistribute it and/or modify it under
+// the terms of the GNU Lesser General Public License as published by the Free
+// Software Foundation; either version 3.0 of the License, or (at your option)
+// any later version.
+// This library is distributed in the hope that it will be useful, but WITHOUT
+// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+// FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
+// details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with this library; if not, write to the Free Software Foundation, Inc.,
+// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+//------------------------------------------------------------------------------
+#ifndef OST_MOL_BASE_BUILDER_HH
+#define OST_MOL_BASE_BUILDER_HH
+
+#include "module_config.hh"
+
+#include "atom_handle.hh"
+#include "residue_handle.hh"
+#include "chain_handle.hh"
+#include "entity_handle.hh"
+#include "xcs_editor.hh"
+
+
+namespace ost { namespace mol {
+
+// a helper class to easily create entities
+class DLLEXPORT Builder {
+public:
+ Builder(): ent_(CreateEntity()), edi_(ent_.EditXCS(BUFFERED_EDIT)) {
+ }
+
+ // conversion to entity handle
+ operator EntityHandle() { return ent_; }
+
+ Builder& Chain(const String& name) {
+ chain_ = edi_.InsertChain(name);
+ res_ = ResidueHandle();
+ atom_ = AtomHandle();
+ return *this;
+ }
+
+ Builder& Residue(const String& name) {
+ res_ = edi_.AppendResidue(chain_, name);
+ atom_ = AtomHandle();
+ return *this;
+ }
+
+ Builder& OneLetterCode(char olc) {
+ res_.SetOneLetterCode(olc);
+ return *this;
+ }
+
+ Builder& Atom(const String& name, const geom::Vec3& pos=geom::Vec3()) {
+ edi_.InsertAtom(res_, name, pos);
+ return *this;
+ }
+private:
+ EntityHandle ent_;
+ ChainHandle chain_;
+ ResidueHandle res_;
+ AtomHandle atom_;
+ XCSEditor edi_;
+
+
+};
+
+}}
+#endif
+
diff --git a/modules/mol/base/tests/CMakeLists.txt b/modules/mol/base/tests/CMakeLists.txt
index 5085b0b10b257fab18361001a1cb7a55b796769d..176f6ad2421f1d381eaf4800c4f2ec3ad2419325 100644
--- a/modules/mol/base/tests/CMakeLists.txt
+++ b/modules/mol/base/tests/CMakeLists.txt
@@ -3,6 +3,7 @@ set(OST_MOL_BASE_UNIT_TESTS
test_chain.cc
test_conn.cc
test_coord_group.cc
+ test_builder.cc
test_delete.cc
test_entity.cc
test_ics.cc
diff --git a/modules/mol/base/tests/test_builder.cc b/modules/mol/base/tests/test_builder.cc
new file mode 100644
index 0000000000000000000000000000000000000000..f9128bca409ca2df578c9829eb1acb2fea99615a
--- /dev/null
+++ b/modules/mol/base/tests/test_builder.cc
@@ -0,0 +1,74 @@
+//------------------------------------------------------------------------------
+// This file is part of the OpenStructure project <www.openstructure.org>
+//
+// Copyright (C) 2008-2011 by the OpenStructure authors
+//
+// This library is free software; you can redistribute it and/or modify it under
+// the terms of the GNU Lesser General Public License as published by the Free
+// Software Foundation; either version 3.0 of the License, or (at your option)
+// any later version.
+// This library is distributed in the hope that it will be useful, but WITHOUT
+// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+// FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
+// details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with this library; if not, write to the Free Software Foundation, Inc.,
+// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+//------------------------------------------------------------------------------
+/*
+ * Authors: Marco Biasini, Juergen Haas
+ */
+#include <ost/mol/builder.hh>
+
+#define BOOST_TEST_DYN_LINK
+#include <boost/test/unit_test.hpp>
+#include <boost/test/auto_unit_test.hpp>
+
+using namespace ost;
+using namespace ost::mol;
+
+BOOST_AUTO_TEST_SUITE( mol_base_builder );
+
+BOOST_AUTO_TEST_CASE(inserts_chains)
+{
+ EntityHandle ent = Builder()
+ .Chain("A")
+ .Chain("B");
+
+ BOOST_CHECK_EQUAL(2, ent.GetChainCount());
+ BOOST_CHECK(ent.FindChain("A").IsValid());
+ BOOST_CHECK(ent.FindChain("B").IsValid());
+}
+
+
+BOOST_AUTO_TEST_CASE(appends_residues) {
+ EntityHandle ent = Builder()
+ .Chain("A")
+ .Residue("GLY")
+ .Residue("GLN");
+
+ BOOST_CHECK_EQUAL(1, ent.GetChainCount());
+ BOOST_CHECK_EQUAL(ent.GetResidueCount(), 2);
+ BOOST_CHECK(ent.FindResidue("A", 1).IsValid());
+ BOOST_CHECK(ent.FindResidue("A", 2).IsValid());
+}
+
+BOOST_AUTO_TEST_CASE(inserts_atoms) {
+ EntityHandle ent = Builder()
+ .Chain("A")
+ .Residue("GLY")
+ .Atom("N")
+ .Atom("CA")
+ .Atom("C")
+ .Atom("O")
+ ;
+
+ BOOST_CHECK_EQUAL(ent.GetAtomCount(), 4);
+ BOOST_CHECK(ent.FindAtom("A", 1, "N").IsValid());
+ BOOST_CHECK(ent.FindAtom("A", 1, "CA").IsValid());
+ BOOST_CHECK(ent.FindAtom("A", 1, "C").IsValid());
+ BOOST_CHECK(ent.FindAtom("A", 1, "O").IsValid());
+}
+
+BOOST_AUTO_TEST_SUITE_END();