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1 package org.ozoneDB.tools.OPP.srcgen.builder;
9
10 import org.ozoneDB.tools.OPP.OPPHelper;
11 import org.ozoneDB.tools.OPP.message.MessageWriter;
12 import org.ozoneDB.tools.OPP.srcgen.ClassBuilder;
13 import org.ozoneDB.tools.OPP.srcgen.BuilderException;
14 import org.ozoneDB.tools.OPP.srcgen.streamfactory.OutputStreamFactory;
15
16 import java.io.*;
17 import java.lang.reflect.Modifier  ;
18
19
34 public class FactoryBuilder implements ClassBuilder {
35 private OutputStreamFactory outputFactory;
36 private String postfix;
37 private PrintWriter out = null;
38 private String [] interfaces;
39 private MessageWriter msgWriter;
40
41 public FactoryBuilder(OutputStreamFactory outputFactory, String postfix) {
42 this.outputFactory = outputFactory;
43 this.postfix = postfix;
44 }
45
46 private void makeCreateInternal(String implementationClass, String type) {
47 out.println(" private " + type + " createInternal(OzonePersonalMetaData personalMeta, OzoneSharedMetaData sharedMeta, Class[] ctorArgTypes, Object[] ctorArgs) throws Exception {");
48 out.println(" String name = null;");
49 out.println(" int access = OzoneInterface.Public;");
50 out.println(" if (personalMeta != null) {");
51 out.println(" name = personalMeta.getName();");
52 out.println(" }");
53 out.println(" if (sharedMeta != null) {");
54 out.println(" access = sharedMeta.getAccess();");
55 out.println(" }");
56 out.println(" return (" + type + ") getDatabase().createObject(" + implementationClass + ".class, access, name, ctorArgTypes, ctorArgs);");
57 out.println(" }\n");
58 }
59
60 private void makeGlobalHeader(String implementationClass) {
61 out.println("// Factory class generated by ozone's OPP ($Revision$).");
62 out.println("// DO NOT EDIT!\n");
63 if (!OPPHelper.packageName(implementationClass).equals("")) {
64 out.println("package " + OPPHelper.packageName(implementationClass) + ";\n");
65 }
66 out.println("import org.ozoneDB.AbstractFactory;");
67 out.println("import org.ozoneDB.OzonePersonalMetaData;");
68 out.println("import org.ozoneDB.OzoneSharedMetaData;");
69 out.println("import org.ozoneDB.OzoneInterface;");
70 out.println("import org.ozoneDB.OzoneInternalException;");
71 out.println("import org.ozoneDB.OzoneProxy;");
72 out.println("import org.ozoneDB.tools.OPP.OPP;\n");
73 }
74
75 private void makeLocalHeader(String simpleClassName) {
76 out.println("/**");
77 out.println(" * <p>This class is generated by OPP. DO NOT EDIT, for it will be overwritten");
78 out.println(" * the next time OPP is run for <code>" + simpleClassName + "</code>.</p>");
79 out.println(" * <p>Factory pattern class for creating ozone objects.</p>");
80 out.println(" * A factory has a bit of a schizophrenic nature: on the client-side it 'links'");
81 out.println(" * to an ExternalDatabase, while on the server-side it does so to the Database");
82 out.println(" * that holds the instances that the factory creates. Note however that a");
83 out.println(" * factory running inside an Ozone server can also be linked to an External");
84 out.println(" * database outside that server (userclient -> server A -> server B). In that");
85 out.println(" * case such a factory would be 'linked' to an ExternalDatabase.</p>");
86 out.println(" * <p>The idea behind factories is threefold:<ul>\n");
87 out.println(" * <li>provide an abstraction from Ozone specific object creation</li>");
88 out.println(" * <li>facilitate creating objects with non-default constructors</li>");
89 out.println(" * <li>provide (almost) the same interface on the server side and the client");
90 out.println(" * side on object creation</li></ul>");
91 out.println(" * The differences in client side and server side operation are:<ul>");
92 out.println(" * <li>on the server side <code>getDefault()</code> returns a factory that is");
93 out.println(" * creates its objects inside that same server database and on the client side");
94 out.println(" * it returns a factory that creates its objects in the default database</li>");
95 out.println(" * <li>In order to use <code>getDefault()<code> on the client side, you need to");
96 out.println(" * call <code>setDefaultDatabaseUrl(String)</code> to specify the default");
97 out.println(" * database.</li>");
98 out.println(" * In a typical real-world scenario where you connect to only one ozone database");
99 out.println(" * you would call <code>setDefaultDatabaseUrl(String)</code> on the client only");
100 out.println(" * once, and for the rest of the programs lifespan call");
101 out.println(" * <code>" + simpleClassName + ".getDefault().create()</code> methods both on the server and");
102 out.println(" * client sides to create objects.</p>");
103 out.println(" * <p>Note: if you do not have a clue what factories are and how they work, you");
104 out.println(" * should probably brush up on your knowledge of");
105 out.println(" * <a HREF=\"http://www.google.com/search?q=java+design+patterns+GoF\">design patterns</a></p>.");
106 out.println(" * @author <a HREF=\"mailto://ozone-db.orgATmekenkampD0Tcom\">Leo Mekenkamp</a>");
107 out.println(" * @since FIXME(since when?)");
108 out.println(" */\n");
109 out.println("public final class " + simpleClassName + " extends AbstractFactory {\n");
110 out.println(" private static class Info implements org.ozoneDB.FactoryClassInfo {");
111 out.println(" public final void defaultDatabaseUrlChanged() {");
112 out.println(" defaultInstance = null;");
113 out.println(" }");
114 out.println(" }\n");
115 out.println(" static {");
116 out.println(" addFactoryClassInfo(new Info());");
117 out.println(" }\n");
118 out.println(" private static " + simpleClassName + " defaultInstance = null;\n");
119 out.println(" /**");
120 out.println(" * On the client side: returns a factory that is linked to a database");
121 out.println(" * specified by the url passed to <code>setDefaultDatabaseUrl</code>. On the");
122 out.println(" * server side: returns a factory that is linked to the server database.");
123 out.println(" * Note that multiple calls to this method return the same value over and");
124 out.println(" * over again, until <code>setDefaultDatabaseUrl</code> has been called.");
125 out.println(" */");
126 out.println(" public static synchronized " + simpleClassName + " getDefault() throws Exception {");
127 out.println(" if (defaultInstance == null) {");
128 out.println(" defaultInstance = new " + simpleClassName + "();");
129 out.println(" }");
130 out.println(" return defaultInstance;");
131 out.println(" }\n");
132 out.println(" /**");
134 out.println(" * <p>Default constructor: creates a factory that is liked to the default");
135 out.println(" * database.</p>");
136 out.println(" */");
137 out.println(" public " + simpleClassName + "() throws Exception {");
138 out.println(" }\n");
139 out.println(" /** <p>Creates a factory that creates its objects in the database specified by");
140 out.println(" * <code>url</code>. Note that this constructor can only be used if the database in");
141 out.println(" * question is not opened by this client. Use <code>" + simpleClassName + "()</code> or");
142 out.println(" * <code>" + simpleClassName + "(Factory)</code> to create a factory for an already opened");
143 out.println(" * database. This might seem strange, or even annoying at first, but it is very");
144 out.println(" * logical from an object oriented point of view: you probably want a factory that");
145 out.println(" * creates its objects in the default database, or in the same realm as another");
146 out.println(" * factory you already have created...</p>");
147 out.println(" * @param databaseUrl url defining the remote database (something like");
148 out.println(" * <code>ozone:remote://localhost:3333</code>)");
149 out.println(" */");
150 out.println(" public " + simpleClassName + "(String databaseUrl) throws Exception {");
151 out.println(" super(databaseUrl);");
152 out.println(" }\n");
153 out.println(" /** <p>Creates a factory that creates its objects in the same database as a specific");
154 out.println(" * other fatory does.</p>");
155 out.println(" * @param factory the factory that creates its objects in the same database as the new factory");
156 out.println(" * should");
157 out.println(" */");
158 out.println(" public " + simpleClassName + "(AbstractFactory factory) {");
159 out.println(" super(factory);");
160 out.println(" }\n");
161 out.println(" /**");
162 out.println(" * Gets called automatically to indicate that the default database has been");
163 out.println(" * closed. DO NOT CALL THIS METHOD YOURSELF.");
164 out.println(" */");
165 out.println(" protected void defaultClosed() {");
166 out.println(" defaultInstance = null;");
167 out.println(" }\n");
168 }
169
170 private void makeObjectForHandle(String type) {
171 out.println(" /**");
172 out.println(" * <p>Retrieves an object through its handle. <emp>Do not use this function");
173 out.println(" * unless you are perfectly sure about what you are doing</emp>. See the");
174 out.println(" * examples for some hands-on information on when to use handles. Note that");
175 out.println(" * normally one would use names or just standard java object references.</p>");
176 out.println(" */");
177 out.println(" public " + type + " objectForHandle(String handle) throws Exception {");
178 out.println(" return (" + type + ") getDatabase().objectForHandle(handle);");
179 out.println(" }\n");
180 }
181
182 private void makeObjectForName(String type) {
183 out.println(" /**");
184 out.println(" * <p>Retrieves an object from the database through its name.</p>");
185 out.println(" */");
186 out.println(" public " + type + " objectForName(String name) throws Exception {");
187 out.println(" return (" + type + ") getDatabase().objectForName(name);");
188 out.println(" }\n");
189 }
190
191 public void init(MessageWriter msgWriter) {
192 this.msgWriter = msgWriter;
193 }
194
195 public void beginClass(int modifer, String fullName, String superClass, String interfaces[]) throws BuilderException {
196 msgWriter.startGeneration("Generating factory for: " + fullName);
197 this.interfaces = interfaces;
198 try {
199 out = new PrintWriter(outputFactory.newInstance(fullName + postfix));
200 } catch (IOException e) {
201 throw new BuilderException(e);
202 }
203 makeGlobalHeader(fullName);
204 makeLocalHeader(OPPHelper.simpleClassName(fullName) + postfix);
205 makeObjectForHandle(interfaces[0]);
206 makeObjectForName(interfaces[0]);
207 makeCreateInternal(fullName, interfaces[0]);
208 }
209
210 public void makeConstructor(int modifier, ClassBuilder.Parameter parameters[], String exceptions[]) throws BuilderException {
211 if (Modifier.isPrivate(modifier)) {
218 return;
219 }
220 String mod;
221 mod = Modifier.toString(modifier);
225 StringBuffer ctorHeader = new StringBuffer ();
226 StringBuffer ctorArgTypes = new StringBuffer ();
227 StringBuffer ctorArgs = new StringBuffer ();
228 for (int i = 0; i < parameters.length; ++i) {
229 String paramType = parameters[i].getType();
230 if (ctorArgTypes.length() > 0) {
231 ctorArgTypes.append(", ");
232 ctorHeader.append(", ");
233 ctorArgs.append(", ");
234 }
235 ctorArgTypes.append(paramType).append(".class");
236 ctorHeader.append(paramType).append(" p").append(i);
237 if (OPPHelper.isPrimitive(paramType)) {
238 ctorArgs.append("new ").append(OPPHelper.wrappercodeForPrimitive(paramType)).append("(");
239 }
240 ctorArgs.append("p").append(i);
241 if (OPPHelper.isPrimitive(paramType)) {
242 ctorArgs.append(")");
243 }
244 }
245 out.println(" /**");
246 out.println(" * <p>Creates a new database object</p>");
247 out.println(" */");
248 out.println(" " + mod + " " + interfaces[0] + " create(" + ctorHeader + ") throws Exception {");
249 if (ctorArgTypes.length() == 0) {
250 out.println(" Class[] ctorArgTypes = null;");
251 out.println(" Object[] ctorArgs = null;");
252 } else {
253 out.println(" Class[] ctorArgTypes = new Class[] {" + ctorArgTypes + "};");
254 out.println(" Object[] ctorArgs = new Object[] {" + ctorArgs + "};");
255 }
256 out.println(" return createInternal(null, null, ctorArgTypes, ctorArgs);");
257 out.println(" }\n");
258 if (ctorHeader.length() > 0) {
260 ctorHeader.insert(0, ", ");
261 }
262 out.println(" /**");
263 out.println(" * <p>Creates a new database object with given metadata</p>");
264 out.println(" */");
265 out.println(" " + mod + " " + interfaces[0] + " create(OzonePersonalMetaData personalMeta, OzoneSharedMetaData sharedMeta" + ctorHeader + ") throws Exception {");
266 if (ctorArgTypes.length() == 0) {
267 out.println(" Class[] ctorArgTypes = null;");
268 out.println(" Object[] ctorArgs = null;");
269 } else {
270 out.println(" Class[] ctorArgTypes = new Class[] {" + ctorArgTypes + "};");
271 out.println(" Object[] ctorArgs = new Object[] {" + ctorArgs + "};");
272 }
273 out.println(" return createInternal(personalMeta, sharedMeta, ctorArgTypes, ctorArgs);");
274 out.println(" }\n");
275 }
276
277 public void makeMethod(int modifier, String name, ClassBuilder.Parameter parameters[], String returnType, String exceptions[], int lockLevel) throws BuilderException {
278 }
279
280 public void endClass() throws BuilderException {
281 out.println("}");
282 out.close();
283 msgWriter.endGeneration();
284 }
285 }
286 |
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