4 package net.sf.openrocket.file.rocksim;
6 import net.sf.openrocket.aerodynamics.WarningSet;
7 import net.sf.openrocket.file.simplesax.ElementHandler;
8 import net.sf.openrocket.material.Material;
9 import net.sf.openrocket.rocketcomponent.RocketComponent;
10 import org.xml.sax.SAXException;
12 import java.lang.reflect.InvocationTargetException;
13 import java.lang.reflect.Method;
14 import java.util.HashMap;
17 * An abstract base class that handles common parsing. All Rocksim component handlers are subclassed from here.
19 * @param <C> the specific RocketComponent subtype for which the concrete handler can create
21 public abstract class BaseHandler<C extends RocketComponent> extends ElementHandler {
24 * The overridden mass.
26 private Double mass = 0d;
30 private Double cg = 0d;
32 * The density of the material in the component.
34 private Double density = 0d;
36 * The internal Rocksim density type.
38 private RocksimDensityType densityType = RocksimDensityType.ROCKSIM_BULK;
43 private String materialName = "";
46 * The SAX method called when the closing element tag is reached.
48 * @param element the element name.
49 * @param attributes attributes of the element.
50 * @param content the textual content of the element.
51 * @param warnings the warning set to store warnings in.
52 * @throws SAXException
56 public void closeElement(String element, HashMap<String, String> attributes, String content, WarningSet warnings)
58 final C component = getComponent();
60 if ("Name".equals(element)) {
61 component.setName(content);
63 if ("KnownMass".equals(element)) {
64 mass = Math.max(0d, Double.parseDouble(content) / RocksimHandler.ROCKSIM_TO_OPENROCKET_MASS);
66 if ("Density".equals(element)) {
67 density = Math.max(0d, Double.parseDouble(content) );
69 if ("KnownCG".equals(element)) {
70 cg = Math.max(0d, Double.parseDouble(content) / RocksimHandler.ROCKSIM_TO_OPENROCKET_LENGTH);
72 if ("UseKnownCG".equals(element)) { //Rocksim sets UseKnownCG to true to control the override of both cg and mass
73 boolean override = "1".equals(content);
74 setOverride(component, override, mass, cg);
76 if ("DensityType".equals(element)) {
77 densityType = RocksimDensityType.fromCode(Integer.parseInt(content));
80 catch (NumberFormatException nfe) {
81 warnings.add("Could not convert " + element + " value of " + content + ". It is expected to be a number.");
89 public void endHandler(String element, HashMap<String, String> attributes, String content, WarningSet warnings)
91 /* Because of the order of XML elements in Rocksim, not all information is known at the time it really needs
92 to be acted upon. So we keep temporary instance variables to be used here at the end of the parsing.
94 density = computeDensity(densityType, density);
95 RocketComponent component = getComponent();
96 updateComponentMaterial(component, materialName, getMaterialType(), density);
100 * Compute the density. Rocksim does strange things with densities. For some streamer material it's in cubic,
101 * rather than square, units. In those cases it needs to be converted to an appropriate SURFACE material density.
102 * Some G10 fiberglass materials are in cubic units, other G10 fiberglass is in square units. And due to a
103 * Rocksim bug, some densities are 0 when they clearly should not be.
105 * This may be overridden for specific component density computations.
107 * @param type the rocksim density
108 * @param rawDensity the density as specified in the Rocksim design file
109 * @return a value in OpenRocket SURFACE density units
111 protected double computeDensity(RocksimDensityType type, double rawDensity) {
112 return rawDensity / type.asOpenRocket();
116 * If the Rocksim component does not override the mass, then create a Material based upon the density defined
117 * for that component. This *should* result in a consistent representation of Cg between Rocksim and OpenRocket.
119 * @param component the component
120 * @param type the type of the material
121 * @param density the density in g/cm^3
122 * @param definedMaterial the material that is currently defined on the component; used only to get the name
123 * as it appears in Rocksim
125 public static void updateComponentMaterial(RocketComponent component, String definedMaterial, Material.Type type,
127 if (definedMaterial != null) {
128 Material custom = createCustomMaterial(type, definedMaterial, density);
129 setMaterial(component, custom);
134 * Override the mass and Cg of the component.
136 * @param component the component
137 * @param override true if any override should happen
138 * @param mass the override mass
139 * @param cg the override cg
141 public static void setOverride(RocketComponent component, boolean override, double mass, double cg) {
143 component.setCGOverridden(override);
144 component.setMassOverridden(override);
145 component.setOverrideSubcomponents(false); //Rocksim does not support this type of override
146 component.setOverrideMass(mass);
147 component.setOverrideCGX(cg);
152 * Get the component this handler is working upon.
154 * @return a component
156 protected abstract C getComponent();
159 * Get the required type of material for this component.
161 * @return the required material type
163 protected abstract Material.Type getMaterialType();
166 * Some CG positions in Rocksim do not correspond to the CG position reference in OpenRocket.
168 * @param theCG the CG value to really use when overriding CG on the OpenRocket component
170 protected void setCG(double theCG) {
175 * Set the material name as specified in the Rocksim design file.
177 * @param content the material name
179 protected void setMaterialName(String content) {
180 materialName = content;
184 * Add child to parent only if the child is compatible. Otherwise add to warning set.
186 * @param parent the parent component
187 * @param child the child component
188 * @param warnings the warning set
190 * @return true if the child is compatible with parent
192 protected static boolean isCompatible(RocketComponent parent, Class<? extends RocketComponent> child, WarningSet warnings) {
193 if (!parent.isCompatible(child)) {
194 warnings.add(child.getName() + " can not be attached to "
195 + parent.getComponentName() + ", ignoring component.");
204 * Create a custom material based on the density. The name of the material is prepended with 'RS: ' to
205 * indicate it came from a RockSim material.
207 * @param type the type of the material
208 * @param name the name of the component
209 * @param density the density
211 * @return a Material instance
213 public static Material createCustomMaterial(Material.Type type, String name, double density) {
214 return Material.newMaterial(type, "RS: " + name, density, true);
218 * Set the material onto an instance of RocketComponent. This is done because only some subtypes of RocketComponent
219 * have the setMaterial method. Unfortunately the supertype cannot be used.
221 * @param component the component who's material is to be set
222 * @param material the material to be set on the component (defined by getComponent())
224 private static void setMaterial(RocketComponent component, Material material) {
226 final Method method = getMethod(component, "setMaterial", new Class[]{Material.class});
227 if (method != null) {
228 method.invoke(component, material);
231 catch (IllegalAccessException ignored) {
233 catch (InvocationTargetException ignored) {
238 * Find a method by name and argument list.
240 * @param component the component who's material is to be seta
241 * @param name the method name
242 * @param args the class types of the parameters
244 * @return the Method instance, or null
246 private static Method getMethod(RocketComponent component, String name, Class[] args) {
247 Method method = null;
249 method = component.getClass().getMethod(name, args);
251 catch (NoSuchMethodException ignored) {