org.drools.KnowledgeBase Java Examples

public void deploy(DeploymentEntity deployment, Map<String, Object> deploymentSettings) {
  log.debug("Processing deployment {}", deployment.getName());

  KnowledgeBuilder knowledgeBuilder = null;

  DeploymentManager deploymentManager = Context.getProcessEngineConfiguration().getDeploymentManager();

  Map<String, ResourceEntity> resources = deployment.getResources();
  for (String resourceName : resources.keySet()) {
    log.info("Processing resource {}", resourceName);
    if (resourceName.endsWith(".drl")) { // is only parsing .drls sufficient? what about other rule dsl's? (@see ResourceType)
      if (knowledgeBuilder == null) {
        knowledgeBuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();
      }
      ResourceEntity resourceEntity = resources.get(resourceName);
      byte[] resourceBytes = resourceEntity.getBytes();
      Resource droolsResource = ResourceFactory.newByteArrayResource(resourceBytes);
      knowledgeBuilder.add(droolsResource, ResourceType.DRL);
    }
  }

  if (knowledgeBuilder != null) {
    KnowledgeBase knowledgeBase = knowledgeBuilder.newKnowledgeBase();
    deploymentManager.getKnowledgeBaseCache().add(deployment.getId(), knowledgeBase);
  }
}
 

private static KnowledgeBase readKnowledgeBase(String drlFileName) {
    KnowledgeBuilder kbuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();
    String configDir = CarbonUtils.getCarbonConfigDirPath();
    String droolsDir = configDir + File.separator + StratosConstants.DROOLS_DIR_NAME;
    Resource resource = ResourceFactory.newFileResource(droolsDir + File.separator + drlFileName);
    kbuilder.add(resource, ResourceType.DRL);
    KnowledgeBuilderErrors errors = kbuilder.getErrors();
    if (errors.size() > 0) {
        for (KnowledgeBuilderError error : errors) {
            log.error(error.getMessage());
        }
        throw new IllegalArgumentException("Could not parse knowledge");
    }
    KnowledgeBase kbase = KnowledgeBaseFactory.newKnowledgeBase();
    kbase.addKnowledgePackages(kbuilder.getKnowledgePackages());
    return kbase;
}
 

public void deploy(DeploymentEntity deployment, Map<String, Object> deploymentSettings) {
  log.debug("Processing deployment {}", deployment.getName());
  
  KnowledgeBuilder knowledgeBuilder = null;

  DeploymentManager deploymentManager = Context
    .getProcessEngineConfiguration()
    .getDeploymentManager();
  
  Map<String, ResourceEntity> resources = deployment.getResources();
  for (String resourceName : resources.keySet()) {
    log.info("Processing resource {}", resourceName);
    if (resourceName.endsWith(".drl")) { // is only parsing .drls sufficient? what about other rule dsl's? (@see ResourceType)
      if (knowledgeBuilder==null) {
        knowledgeBuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();
      }
      ResourceEntity resourceEntity = resources.get(resourceName);
      byte[] resourceBytes = resourceEntity.getBytes();
      Resource droolsResource = ResourceFactory.newByteArrayResource(resourceBytes);
      knowledgeBuilder.add(droolsResource, ResourceType.DRL);
    }
  }
  
  if (knowledgeBuilder!=null) {
    KnowledgeBase knowledgeBase = knowledgeBuilder.newKnowledgeBase();
    deploymentManager.getKnowledgeBaseCache().add(deployment.getId(), knowledgeBase);
  }
}
 

public void execute(DelegateExecution execution) {
  ProcessDefinition processDefinition = ProcessDefinitionUtil.getProcessDefinition(execution.getProcessDefinitionId());
  String deploymentId = processDefinition.getDeploymentId();

  KnowledgeBase knowledgeBase = RulesHelper.findKnowledgeBaseByDeploymentId(deploymentId);
  StatefulKnowledgeSession ksession = knowledgeBase.newStatefulKnowledgeSession();

  if (variablesInputExpressions != null) {
    Iterator<Expression> itVariable = variablesInputExpressions.iterator();
    while (itVariable.hasNext()) {
      Expression variable = itVariable.next();
      ksession.insert(variable.getValue(execution));
    }
  }

  if (!rulesExpressions.isEmpty()) {
    RulesAgendaFilter filter = new RulesAgendaFilter();
    Iterator<Expression> itRuleNames = rulesExpressions.iterator();
    while (itRuleNames.hasNext()) {
      Expression ruleName = itRuleNames.next();
      filter.addSuffic(ruleName.getValue(execution).toString());
    }
    filter.setAccept(!exclude);
    ksession.fireAllRules(filter);

  } else {
    ksession.fireAllRules();
  }

  Collection<Object> ruleOutputObjects = ksession.getObjects();
  if (ruleOutputObjects != null && !ruleOutputObjects.isEmpty()) {
    Collection<Object> outputVariables = new ArrayList<Object>();
    for (Object object : ruleOutputObjects) {
      outputVariables.add(object);
    }
    execution.setVariable(resultVariable, outputVariables);
  }
  ksession.dispose();
  leave(execution);
}
 

private AutoscalerRuleEvaluator() {
    knowledgeBases = new HashMap<String, KnowledgeBase>();
    parseAndBuildKnowledgeBaseForDroolsFile(StratosConstants.OBSOLETE_CHECK_DROOL_FILE);
    parseAndBuildKnowledgeBaseForDroolsFile(StratosConstants.SCALE_CHECK_DROOL_FILE);
    parseAndBuildKnowledgeBaseForDroolsFile(StratosConstants.MIN_CHECK_DROOL_FILE);
    parseAndBuildKnowledgeBaseForDroolsFile(StratosConstants.MAX_CHECK_DROOL_FILE);
    parseAndBuildKnowledgeBaseForDroolsFile(StratosConstants.DEPENDENT_SCALE_CHECK_DROOL_FILE);


}
 

public void parseAndBuildKnowledgeBaseForDroolsFile(String drlFileName) {
    KnowledgeBase knowledgeBase = readKnowledgeBase(drlFileName);
    if (knowledgeBase == null) {
        log.error("Knowledge base couldn't be read for" +
                " [drool-file] " + drlFileName);
    } else {
        knowledgeBases.put(drlFileName, knowledgeBase);
        if (log.isDebugEnabled()) {
            log.debug("Drools file is parsed successfully:" +
                    " [ file-name] " + drlFileName);
        }
    }
}
 

public void execute(DelegateExecution execution) {
  ActivityExecution activityExecution = (ActivityExecution) execution;
  PvmProcessDefinition processDefinition = activityExecution.getActivity().getProcessDefinition();
  String deploymentId = processDefinition.getDeploymentId();
  
  KnowledgeBase knowledgeBase = RulesHelper.findKnowledgeBaseByDeploymentId(deploymentId); 
  StatefulKnowledgeSession ksession = knowledgeBase.newStatefulKnowledgeSession();
  
  if (variablesInputExpressions != null) {
    Iterator<Expression> itVariable = variablesInputExpressions.iterator();
    while (itVariable.hasNext()) {
      Expression variable = itVariable.next();
      ksession.insert(variable.getValue(execution));
    }
  }
  
  if (!rulesExpressions.isEmpty()) {
    RulesAgendaFilter filter = new RulesAgendaFilter();
    Iterator<Expression> itRuleNames = rulesExpressions.iterator();
    while (itRuleNames.hasNext()) {
      Expression ruleName = itRuleNames.next();
      filter.addSuffic(ruleName.getValue(execution).toString());
    }
    filter.setAccept(!exclude);
    ksession.fireAllRules(filter);
    
  } else {
    ksession.fireAllRules();
  }
  
  Collection<Object> ruleOutputObjects = ksession.getObjects();
  if (ruleOutputObjects != null && !ruleOutputObjects.isEmpty()) {
    Collection<Object> outputVariables = new ArrayList<Object>();
    for (Object object : ruleOutputObjects) {
      outputVariables.add(object);
    }
    execution.setVariable(resultVariable, outputVariables);
  }
  ksession.dispose();
  leave(activityExecution);
}