Activator.java

   1 package org.argeo.cms.internal.kernel;
   2
   3 import java.util.UUID;
   4
   5 import org.apache.commons.logging.Log;
   6 import org.apache.commons.logging.LogFactory;
   7 import org.argeo.security.SystemAuthentication;
   8 import org.osgi.framework.BundleActivator;
   9 import org.osgi.framework.BundleContext;
  10
  11 /**
  12  * Activates the {@link Kernel} from the provided {@link BundleContext}. Gives
  13  * access to kernel information for the rest of the bundle (and only it)
  14  */
  15 public class Activator implements BundleActivator {
  16         private final Log log = LogFactory.getLog(Activator.class);
  17
  18         private final static String systemKey;
  19         static {
  20                 systemKey = UUID.randomUUID().toString();
  21                 System.setProperty(SystemAuthentication.SYSTEM_KEY_PROPERTY, systemKey);
  22         }
  23
  24         private static BundleContext bundleContext;
  25         private Kernel kernel;
  26
  27         @Override
  28         public void start(BundleContext context) throws Exception {
  29                 assert bundleContext == null;
  30                 assert kernel == null;
  31                 bundleContext = context;
  32                 try {
  33                         kernel = new Kernel();
  34                         kernel.init();
  35                 } catch (Exception e) {
  36                         log.error("Cannot boot kernel", e);
  37                 }
  38         }
  39
  40         @Override
  41         public void stop(BundleContext context) throws Exception {
  42                 kernel.destroy();
  43                 kernel = null;
  44                 bundleContext = null;
  45         }
  46
  47         /**
  48          * Singleton interface to the {@link BundleContext} related to the calling
  49          * thread.
  50          *
  51          * @BundleScope
  52          */
  53         public static BundleContext getBundleContext() {
  54                 return bundleContext;
  55         }
  56
  57         /**
  58          * @return a String which is guaranteed to be unique between and constant
  59          *         within a Java static context (typically a VM launch)
  60          * @BundleScope
  61          */
  62         public final static String getSystemKey() {
  63                 return systemKey;
  64         }
  65 }