wamblee.org Git - utils/blob - system/general/src/main/java/org/wamblee/system/Container.java

   1 package org.wamblee.system;
   2
   3 import java.util.ArrayList;
   4 import java.util.Arrays;
   5 import java.util.List;
   6
   7 import org.apache.commons.logging.Log;
   8 import org.apache.commons.logging.LogFactory;
   9
  10 import sun.util.LocaleServiceProviderPool.LocalizedObjectGetter;
  11
  12 /**
  13  * Composite system consisting of multiple subsystems.
  14  *
  15  * @author Erik Brakkee
  16  */
  17 public class Container extends AbstractComponent {
  18
  19         private static final Log LOG = LogFactory.getLog(Container.class);
  20
  21         private Component[] _systems;
  22
  23         /**
  24          * Construcst the composite system.
  25          * @param aName Name of the system.
  26          * @param aRegistry Service registry.
  27          * @param aSystems Subsystems.
  28          * @param aProvided Provided services of the system.
  29          * @param aRequired Required services by the system.
  30          */
  31         public Container(String aName, ServiceRegistry aRegistry, Component[] aSystems,
  32                         ProvidedInterfaceDescriptor[] aProvided, RequiredInterfaceDescriptor[] aRequired) {
  33                 super(aName, aRegistry, aProvided, aRequired);
  34                 _systems = aSystems;
  35                 validate();
  36         }
  37
  38         /**
  39          * Validates the subsystems together to check that there are
  40          * no required services not in the required list and
  41          * no services in the provided list that cannot be provided.
  42          * Also logs a warning in case of superfluous requirements.
  43          */
  44         private void validate() {
  45                 List<InterfaceDescriptor> provided = new ArrayList<InterfaceDescriptor>();
  46                 for (Component system : _systems) {
  47                         provided.addAll(Arrays.asList(system.getProvidedServices()));
  48                 }
  49
  50                 List<InterfaceDescriptor> required = new ArrayList<InterfaceDescriptor>();
  51                 for (Component system : _systems) {
  52                         required.addAll(Arrays.asList(system.getRequiredServices()));
  53                 }
  54
  55                 for (InterfaceDescriptor service : getProvidedServices()) {
  56                         if (!(provided.contains(service))) {
  57                                 throw new SystemAssemblyException(getName() + ": Service '" + service
  58                                                 + "' is not provided by any of the subsystems");
  59                         }
  60                 }
  61
  62                 for (InterfaceDescriptor service : getRequiredServices()) {
  63                         if (!(required.contains(service))) {
  64                                 info("Service '"
  65                                                 + service
  66                                                 + "' indicated as required is not actually required by any of the subsystems");
  67                         }
  68                 }
  69
  70                 List<InterfaceDescriptor> reallyRequired = new ArrayList<InterfaceDescriptor>(
  71                                 required);
  72                 for (InterfaceDescriptor service : provided) {
  73                         reallyRequired.remove(service);
  74                 }
  75                 for (InterfaceDescriptor service: getRequiredServices()) {
  76                         reallyRequired.remove(service);
  77                 }
  78                 String missingRequired = "";
  79                 for (InterfaceDescriptor service: reallyRequired) {
  80                         missingRequired += service + "\n";
  81                 }
  82                 if ( missingRequired.length() > 0 ) {
  83                         throw new SystemAssemblyException(getName() + ": missing required services\n" + missingRequired);
  84                 }
  85         }
  86
  87         @Override
  88         protected void doStart(String aContext, Service[] aRequiredServices) {
  89                 List<ProvidedInterfaceDescriptor> descriptors = new ArrayList<ProvidedInterfaceDescriptor>();
  90                 for (Service service : aRequiredServices) {
  91                         descriptors.add(service.getDescriptor());
  92                 }
  93                 SystemAssembler assembler = new SystemAssembler(aContext + "." + getName(), _systems,
  94                                 descriptors.toArray(new ProvidedInterfaceDescriptor[0]));
  95                 assembler.start(getRegistry(), aRequiredServices);
  96         }
  97
  98         @Override
  99         protected void doStop() {
 100                 for (int i = _systems.length-1; i >= 0; i--) {
 101                         _systems[i].stop();
 102                 }
 103         }
 104
 105         private void info(String aMsg) {
 106                 LOG.info(getName() + ": " + aMsg);
 107         }
 108
 109 }