1 // ****************************************************************************** 2 // 3 // Title: Force Field X. 4 // Description: Force Field X - Software for Molecular Biophysics. 5 // Copyright: Copyright (c) Michael J. Schnieders 2001-2025. 6 // 7 // This file is part of Force Field X. 8 // 9 // Force Field X is free software; you can redistribute it and/or modify it 10 // under the terms of the GNU General Public License version 3 as published by 11 // the Free Software Foundation. 12 // 13 // Force Field X is distributed in the hope that it will be useful, but WITHOUT 14 // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 15 // FOR A PARTICULAR PURPOSE. See the GNU General Public License for more 16 // details. 17 // 18 // You should have received a copy of the GNU General Public License along with 19 // Force Field X; if not, write to the Free Software Foundation, Inc., 59 Temple 20 // Place, Suite 330, Boston, MA 02111-1307 USA 21 // 22 // Linking this library statically or dynamically with other modules is making a 23 // combined work based on this library. Thus, the terms and conditions of the 24 // GNU General Public License cover the whole combination. 25 // 26 // As a special exception, the copyright holders of this library give you 27 // permission to link this library with independent modules to produce an 28 // executable, regardless of the license terms of these independent modules, and 29 // to copy and distribute the resulting executable under terms of your choice, 30 // provided that you also meet, for each linked independent module, the terms 31 // and conditions of the license of that module. An independent module is a 32 // module which is not derived from or based on this library. If you modify this 33 // library, you may extend this exception to your version of the library, but 34 // you are not obligated to do so. If you do not wish to do so, delete this 35 // exception statement from your version. 36 // 37 // ****************************************************************************** 38 package ffx.openmm; 39 40 import static edu.uiowa.jopenmm.OpenMMLibrary.OpenMM_CustomExternalForce_addParticle; 41 import static edu.uiowa.jopenmm.OpenMMLibrary.OpenMM_CustomExternalForce_addPerParticleParameter; 42 import static edu.uiowa.jopenmm.OpenMMLibrary.OpenMM_CustomExternalForce_create; 43 import static edu.uiowa.jopenmm.OpenMMLibrary.OpenMM_CustomExternalForce_destroy; 44 45 /** 46 * Custom External Force. 47 */ 48 public class CustomExternalForce extends Force { 49 50 /** 51 * OpenMM CustomExternalForce constructor. 52 * 53 * @param energy The energy expression. 54 */ 55 public CustomExternalForce(String energy) { 56 pointer = OpenMM_CustomExternalForce_create(energy); 57 } 58 59 /** 60 * Add per particle parameter. 61 * 62 * @param parameterName The parameter name. 63 */ 64 public void addPerParticleParameter(String parameterName) { 65 OpenMM_CustomExternalForce_addPerParticleParameter(pointer, parameterName); 66 } 67 68 /** 69 * Add a particle to the force. 70 * 71 * @param index The particle index. 72 * @param particleParameters The particle parameters. 73 */ 74 public void addParticle(int index, DoubleArray particleParameters) { 75 OpenMM_CustomExternalForce_addParticle(pointer, index, particleParameters.getPointer()); 76 } 77 78 /** 79 * Destroy the force. 80 */ 81 public void destroy() { 82 if (pointer != null) { 83 OpenMM_CustomExternalForce_destroy(pointer); 84 pointer = null; 85 } 86 } 87 88 }