demo/plugins/org.argeo.demo.i18n/src/main/java/org/argeo/demo/i18n/ImplementationLoader.java

   1 package org.argeo.demo.i18n;
   2
   3 import java.text.MessageFormat;
   4
   5 /**
   6  * This class enable single sourcing between RAP and RCP. For this to run
   7  * correctly, following conventions must be respected:
   8  * <ul>
   9  * <li>Given the fact that a common interface named Xxx is defined in package
  10  * aa.bb.cc, corresponding implementation named XxxImpl must be found in package
  11  * aa.bb.cc.specific of both RAP and RCP UI bundles.
  12  *
  13  * thanks to {@link http
  14  * ://eclipsesource.com/en/info/rcp-rap-single-sourcing-guideline/}, chapter 7
  15  */
  16
  17 public class ImplementationLoader {
  18         // private final static Log log = LogFactory
  19         // .getLog(ImplementationLoader.class);
  20
  21         public static Object newInstance(
  22                         @SuppressWarnings("rawtypes") final Class type) {
  23                 String name = type.getName();
  24                 // manually construct the implementation name for the given interface,
  25                 // assuming that convention have been respected.
  26                 String cName = type.getCanonicalName();
  27                 String pName = cName.substring(0, cName.lastIndexOf('.') + 1);
  28                 String sName = cName.substring(cName.lastIndexOf('.') + 1);
  29                 String implName = pName + "specific." + sName + "Impl";
  30                 // String implName = cName + "Impl";
  31                 Object result = null;
  32                 try {
  33                         result = type.getClassLoader().loadClass(implName).newInstance();
  34                 } catch (Throwable throwable) {
  35                         String txt = "Could not load implementation for {0}";
  36                         String msg = MessageFormat.format(txt, new Object[] { name });
  37                         throw new RuntimeException(msg, throwable);
  38                 }
  39                 return result;
  40         }
  41 }