* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
- */
+ */
package org.wamblee.system.core;
import java.util.ArrayList;
import org.apache.commons.logging.LogFactory;
/**
- * Composite system consisting of multiple subsystems.
- *
+ * Composite system consisting of multiple subsystems.
+ *
* @author Erik Brakkee
*/
public class Container extends AbstractComponent {
}
public static ProvidedInterface[] filterProvidedServices(
- RequiredInterface aRequired,
- Collection<ProvidedInterface> aProvided) {
+ RequiredInterface aRequired, Collection<ProvidedInterface> aProvided) {
List<ProvidedInterface> provided = new ArrayList<ProvidedInterface>();
for (ProvidedInterface descriptor : aProvided) {
if (aRequired.implementedBy(descriptor)) {
}
return provided.toArray(new ProvidedInterface[0]);
}
-
+
/**
- * Construcst the composite system.
- * @param aName Name of the system.
- * @param aRegistry Service registry.
- * @param aSystems Subsystems.
- * @param aProvided Provided services of the system.
- * @param aRequired Required services by the system.
+ * Construcst the composite system.
+ *
+ * @param aName
+ * Name of the system.
+ * @param aRegistry
+ * Service registry.
+ * @param aSystems
+ * Subsystems.
+ * @param aProvided
+ * Provided services of the system.
+ * @param aRequired
+ * Required services by the system.
*/
public Container(String aName, Component[] aSystems,
ProvidedInterface[] aProvided, RequiredInterface[] aRequired) {
super(aName, aProvided, aRequired);
_systems = aSystems;
- for (Component component: aSystems) {
+ for (Component component : aSystems) {
component.addContext(getQualifiedName());
}
validate(aRequired);
}
/**
- * Validates the subsystems together to check that there are
- * no required services not in the required list and
- * no services in the provided list that cannot be provided.
- * Also logs a warning in case of superfluous requirements.
+ * Validates the subsystems together to check that there are no required
+ * services not in the required list and no services in the provided list
+ * that cannot be provided. Also logs a warning in case of superfluous
+ * requirements.
*/
private void validate(RequiredInterface[] aRequired) {
List<ProvidedInterface> provided = new ArrayList<ProvidedInterface>();
for (ProvidedInterface service : getProvidedInterfaces()) {
if (!(provided.contains(service))) {
- throw new SystemAssemblyException(getName() + ": Service '" + service
+ throw new SystemAssemblyException(getName() + ": Service '"
+ + service
+ "' is not provided by any of the subsystems");
}
}
required);
// Compute all required interfaces that are not provided
for (ProvidedInterface service : provided) {
- List<RequiredInterface> fulfilled =
- Arrays.asList(filterRequiredServices(service,
- reallyRequired));
- reallyRequired.removeAll(fulfilled);
+ List<RequiredInterface> fulfilled = Arrays
+ .asList(filterRequiredServices(service, reallyRequired));
+ reallyRequired.removeAll(fulfilled);
}
// Now the remaining interfaces should be covered by the required
- // list.
+ // list.
reallyRequired.removeAll(Arrays.asList(aRequired));
-
+
String missingRequired = "";
- for (RequiredInterface service: reallyRequired) {
+ for (RequiredInterface service : reallyRequired) {
missingRequired += service + "\n";
}
- if ( missingRequired.length() > 0 ) {
- throw new SystemAssemblyException(getName() + ": missing required services\n" + missingRequired);
+ if (missingRequired.length() > 0) {
+ throw new SystemAssemblyException(getName()
+ + ": missing required services\n" + missingRequired);
}
}
@Override
protected void doStart() {
List<ProvidedInterface> provided = new ArrayList<ProvidedInterface>();
-
+
// all interfaces from the required list of this container are
// provided to the components inside it.
RequiredInterface[] required = getRequiredInterfaces();
- for (RequiredInterface intf: required) {
- ProvidedInterface provider = intf.getProvider();
- if ( provider == null ) {
- throw new SystemAssemblyException(getQualifiedName() + ": required interface '" + intf +"' is not provided");
- }
+ for (RequiredInterface intf : required) {
+ ProvidedInterface provider = intf.getProvider();
+ if (provider == null) {
+ throw new SystemAssemblyException(getQualifiedName()
+ + ": required interface '" + intf + "' is not provided");
+ }
provided.add(intf.getProvider());
}
-
+
startImpl();
}
-
+
/**
* Starts the subsystems.
*
private void startImpl() {
LOG.info("Starting '" + getQualifiedName() + "'");
List<ProvidedInterface> allProvided = new ArrayList<ProvidedInterface>();
-
- // Add the provides of all externally required interfaces to the list of available
+
+ // Add the provides of all externally required interfaces to the list of
+ // available
// interfaces
- for (RequiredInterface required: getRequiredInterfaces()) {
+ for (RequiredInterface required : getRequiredInterfaces()) {
allProvided.add(required.getProvider());
}
-
+
+ List<Component> started = new ArrayList<Component>();
for (Component system : _systems) {
- // Check if all required services are already provided by earlier
- // systems.
- RequiredInterface[] required = system.getRequiredInterfaces();
-
- for (RequiredInterface descriptor : required) {
- ProvidedInterface[] filtered = filterProvidedServices(
- descriptor, allProvided);
-
- if (filtered.length == 0) {
- throw new SystemAssemblyException(
- "Service '"
- + descriptor
- + "' required by system '"
- + system
- + "' is not provided by systems that are started earlier");
+ try {
+ // Check if all required services are already provided by
+ // earlier
+ // systems.
+ RequiredInterface[] required = system.getRequiredInterfaces();
+
+ for (RequiredInterface descriptor : required) {
+ ProvidedInterface[] filtered = filterProvidedServices(
+ descriptor, allProvided);
+
+ if (filtered.length == 0) {
+ throw new SystemAssemblyException(
+ "Service '"
+ + descriptor
+ + "' required by system '"
+ + system
+ + "' is not provided by systems that are started earlier");
+ }
+ if (filtered.length > 1) {
+ throw new SystemAssemblyException(
+ "Service '"
+ + descriptor
+ + "' required by system '"
+ + system
+ + "' matches multiple services provided by other systems: "
+ + Arrays.asList(filtered));
+ }
+ descriptor.setProvider(filtered[0]);
}
- if (filtered.length > 1) {
- throw new SystemAssemblyException(
- "Service '"
- + descriptor
- + "' required by system '"
- + system
- + "' matches multiple services provided by other systems: " +
- Arrays.asList(filtered));
+
+ // Start the service.
+ system.start();
+ started.add(system);
+
+ // add all provided services
+ ProvidedInterface[] provided = system.getProvidedInterfaces();
+ allProvided.addAll(Arrays.asList(provided));
+ } catch (SystemAssemblyException e) {
+ throw e;
+ } catch (RuntimeException e) {
+ LOG.error(getQualifiedName() + ": could not start '"
+ + system.getQualifiedName() + "'", e);
+ // an exception occurred, stop the successfully started
+ // systems
+ for (int i = started.size() - 1; i >= 0; i--) {
+ try {
+ started.get(i).stop();
+ } catch (Throwable t) {
+ LOG.error(getQualifiedName() + ": error stopping "
+ + started.get(i).getQualifiedName());
+ }
}
- descriptor.setProvider(filtered[0]);
+ throw e;
}
-
- // Start the service.
- system.start();
-
- // add all provided services
- ProvidedInterface[] provided = system.getProvidedInterfaces();
- allProvided.addAll(Arrays.asList(provided));
}
+
}
-
@Override
protected void doStop() {
- for (int i = _systems.length-1; i >= 0; i--) {
+ for (int i = _systems.length - 1; i >= 0; i--) {
_systems[i].stop();
}
}
git://wamblee.org / utils / blobdiff