wamblee.org Git - utils/blob - system/general/src/main/java/org/wamblee/system/CompositeSystem.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 public class CompositeSystem extends AbstractSubSystem {
  16
  17         private static final Log LOG = LogFactory.getLog(CompositeSystem.class);
  18
  19         private SubSystem[] _systems;
  20
  21         /**
  22          * Construcst the composite system.
  23          * @param aName Name of the system.
  24          * @param aRegistry Service registry.
  25          * @param aSystems Subsystems.
  26          * @param aProvided Provided services of the system.
  27          * @param aRequired Required services by the system.
  28          */
  29         public CompositeSystem(String aName, ServiceRegistry aRegistry, SubSystem[] aSystems,
  30                         ServiceDescriptor[] aProvided, ServiceDescriptor[] aRequired) {
  31                 super(aName, aRegistry, aProvided, aRequired);
  32                 _systems = aSystems;
  33                 validate();
  34         }
  35
  36         /**
  37          * Validates the subsystems together to check that there are
  38          * no required services not in the required list and
  39          * no services in the provided list that cannot be provided.
  40          * Also logs a warning in case of superfluous requirements.
  41          */
  42         private void validate() {
  43                 List<ServiceDescriptor> provided = new ArrayList<ServiceDescriptor>();
  44                 for (SubSystem system : _systems) {
  45                         provided.addAll(Arrays.asList(system.getProvidedServices()));
  46                 }
  47
  48                 List<ServiceDescriptor> required = new ArrayList<ServiceDescriptor>();
  49                 for (SubSystem system : _systems) {
  50                         required.addAll(Arrays.asList(system.getRequiredServices()));
  51                 }
  52
  53                 for (ServiceDescriptor service : getProvidedServices()) {
  54                         if (!(provided.contains(service))) {
  55                                 throw new SystemAssemblyException(getName() + ": Service '" + service
  56                                                 + "' is not provided by any of the subsystems");
  57                         }
  58                 }
  59
  60                 for (ServiceDescriptor service : getRequiredServices()) {
  61                         if (!(required.contains(service))) {
  62                                 info("Service '"
  63                                                 + service
  64                                                 + "' indicated as required is not actually required by any of the subsystems");
  65                         }
  66                 }
  67
  68                 List<ServiceDescriptor> reallyRequired = new ArrayList<ServiceDescriptor>(
  69                                 required);
  70                 for (ServiceDescriptor service : provided) {
  71                         reallyRequired.remove(service);
  72                 }
  73                 for (ServiceDescriptor service: getRequiredServices()) {
  74                         reallyRequired.remove(service);
  75                 }
  76                 for (ServiceDescriptor service: reallyRequired) {
  77                         throw new SystemAssemblyException(getName() + ": " + "Service '" + service + "' is not provided internally and is not indicated as required for this sub system");
  78                 }
  79         }
  80
  81         @Override
  82         protected void doStart(String aContext, Service[] aRequiredServices) {
  83                 List<ProvidedServiceDescriptor> descriptors = new ArrayList<ProvidedServiceDescriptor>();
  84                 for (Service service : aRequiredServices) {
  85                         descriptors.add(service.getDescriptor());
  86                 }
  87                 SystemAssembler assembler = new SystemAssembler(aContext + "." + getName(), _systems,
  88                                 descriptors.toArray(new ProvidedServiceDescriptor[0]));
  89                 assembler.start(getRegistry(), aRequiredServices);
  90         }
  91
  92         @Override
  93         protected void doStop() {
  94                 // Empty.
  95         }
  96
  97         private void info(String aMsg) {
  98                 LOG.info(getName() + ": " + aMsg);
  99         }
 100
 101 }