Define griffin plain-vanilla hook.

the purpose of hook is for integration with components outside. Griffin would offer information about internal task status.

Task: GRIFFIN-200

Author: Eugene <liujin@apache.org>
Author: William Guo <guoyp@apache.org>

Closes #444 from toyboxman/hook.
diff --git a/service/src/main/java/org/apache/griffin/core/event/EventPointcutType.java b/service/src/main/java/org/apache/griffin/core/event/EventPointcutType.java
new file mode 100644
index 0000000..166372d
--- /dev/null
+++ b/service/src/main/java/org/apache/griffin/core/event/EventPointcutType.java
@@ -0,0 +1,26 @@
+/*
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, 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.apache.griffin.core.event;
+
+public enum EventPointcutType {
+    BEFORE,
+    PENDING,
+    AFTER
+}
diff --git a/service/src/main/java/org/apache/griffin/core/event/EventSourceType.java b/service/src/main/java/org/apache/griffin/core/event/EventSourceType.java
new file mode 100644
index 0000000..6bca570
--- /dev/null
+++ b/service/src/main/java/org/apache/griffin/core/event/EventSourceType.java
@@ -0,0 +1,25 @@
+/*
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, 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.apache.griffin.core.event;
+
+public enum EventSourceType {
+    JOB,
+    MEASURE
+}
diff --git a/service/src/main/java/org/apache/griffin/core/event/EventType.java b/service/src/main/java/org/apache/griffin/core/event/EventType.java
new file mode 100644
index 0000000..b00a9b0
--- /dev/null
+++ b/service/src/main/java/org/apache/griffin/core/event/EventType.java
@@ -0,0 +1,26 @@
+/*
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, 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.apache.griffin.core.event;
+
+public enum EventType {
+    CREATION_EVENT,
+    CHANGE_EVENT,
+    REMOVAL_EVENT
+}
diff --git a/service/src/main/java/org/apache/griffin/core/event/GriffinAbstractEvent.java b/service/src/main/java/org/apache/griffin/core/event/GriffinAbstractEvent.java
new file mode 100644
index 0000000..db29e44
--- /dev/null
+++ b/service/src/main/java/org/apache/griffin/core/event/GriffinAbstractEvent.java
@@ -0,0 +1,57 @@
+/*
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, 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.apache.griffin.core.event;
+
+public abstract class GriffinAbstractEvent<T> implements GriffinEvent<T> {
+    private T source;
+    private EventType type;
+    private EventSourceType sourceType;
+    private EventPointcutType pointcutType;
+
+    public GriffinAbstractEvent(T source,
+                                EventType type,
+                                EventSourceType sourceType,
+                                EventPointcutType pointcutType) {
+        this.source = source;
+        this.type = type;
+        this.sourceType = sourceType;
+        this.pointcutType = pointcutType;
+    }
+
+    @Override
+    public EventType getType() {
+        return this.type;
+    }
+
+    @Override
+    public EventPointcutType getPointcut() {
+        return pointcutType;
+    }
+
+    @Override
+    public EventSourceType getSourceType() {
+        return sourceType;
+    }
+
+    @Override
+    public T getSource() {
+        return source;
+    }
+}
diff --git a/service/src/main/java/org/apache/griffin/core/event/GriffinEvent.java b/service/src/main/java/org/apache/griffin/core/event/GriffinEvent.java
new file mode 100644
index 0000000..cff6163
--- /dev/null
+++ b/service/src/main/java/org/apache/griffin/core/event/GriffinEvent.java
@@ -0,0 +1,54 @@
+/*
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, 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.apache.griffin.core.event;
+
+/**
+ * A semantic event which indicates that a griffin-defined action occurred.
+ * This high-level event is generated by an action (such as an
+ * <code>addJob</code>) when the task-specific action occurs.
+ * The event is passed to every <code>GriffinHook</code> object
+ * that registered to receive such events using configuration.
+ *
+ * @author Eugene Liu
+ * @since 0.3
+ */
+public interface GriffinEvent<T> {
+    /**
+     * @return concrete event type
+     */
+    EventType getType();
+
+    /**
+     * @return concrete event pointcut type
+     */
+    EventPointcutType getPointcut();
+
+    /**
+     * @return concrete event source type
+     */
+    EventSourceType getSourceType();
+
+    /**
+     * The object on which the Event initially occurred.
+     *
+     * @return The object on which the Event initially occurred.
+     */
+    T getSource();
+}
diff --git a/service/src/main/java/org/apache/griffin/core/event/GriffinEventManager.java b/service/src/main/java/org/apache/griffin/core/event/GriffinEventManager.java
new file mode 100644
index 0000000..996d7a7
--- /dev/null
+++ b/service/src/main/java/org/apache/griffin/core/event/GriffinEventManager.java
@@ -0,0 +1,59 @@
+/*
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, 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.apache.griffin.core.event;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.context.ApplicationContext;
+import org.springframework.stereotype.Component;
+
+import javax.annotation.PostConstruct;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Set;
+
+@Component
+public class GriffinEventManager {
+    @Autowired
+    private ApplicationContext applicationContext;
+
+    @Value("#{'${internal.event.listeners}'.split(',')}")
+    private Set<String> enabledListeners;
+
+    private List<GriffinHook> eventListeners;
+
+    @PostConstruct
+    void initializeListeners() {
+        List<GriffinHook> eventListeners = new ArrayList<>();
+        applicationContext.getBeansOfType(GriffinHook.class)
+                .forEach((beanName, listener) -> {
+                    if (enabledListeners.contains(beanName)) {
+                        eventListeners.add(listener);
+                    }
+                });
+        this.eventListeners = eventListeners;
+    }
+
+    public void notifyListeners(GriffinEvent event) {
+        eventListeners.forEach(listener -> {
+            listener.onEvent(event);
+        });
+    }
+}
diff --git a/service/src/main/java/org/apache/griffin/core/event/GriffinHook.java b/service/src/main/java/org/apache/griffin/core/event/GriffinHook.java
new file mode 100644
index 0000000..5090648
--- /dev/null
+++ b/service/src/main/java/org/apache/griffin/core/event/GriffinHook.java
@@ -0,0 +1,42 @@
+/*
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, 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.apache.griffin.core.event;
+
+import org.apache.griffin.core.exception.GriffinException;
+
+/**
+ * The Hook interface for receiving internal events.
+ * The class that is interested in processing an event
+ * implements this interface, and the object created with that
+ * class is registered to griffin, using the configuration.
+ * When the event occurs, that object's <code>onEvent</code> method is
+ * invoked.
+ *
+ * @author Eugene Liu
+ * @since 0.3
+ */
+public interface GriffinHook {
+    /**
+     * Invoked when an action occurs.
+     *
+     * @see GriffinEvent
+     */
+    void onEvent(GriffinEvent event) throws GriffinException;
+}
diff --git a/service/src/main/java/org/apache/griffin/core/event/JobEvent.java b/service/src/main/java/org/apache/griffin/core/event/JobEvent.java
new file mode 100644
index 0000000..5fdea0f
--- /dev/null
+++ b/service/src/main/java/org/apache/griffin/core/event/JobEvent.java
@@ -0,0 +1,60 @@
+/*
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, 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.apache.griffin.core.event;
+
+import org.apache.griffin.core.job.entity.AbstractJob;
+
+public class JobEvent extends GriffinAbstractEvent<AbstractJob> {
+
+    private JobEvent(AbstractJob source,
+                     EventType type,
+                     EventSourceType sourceType,
+                     EventPointcutType pointcutType) {
+        super(source, type, sourceType, pointcutType);
+    }
+
+    public static JobEvent yieldJobEventBeforeCreation(AbstractJob source) {
+        return new JobEvent(source,
+                EventType.CREATION_EVENT,
+                EventSourceType.JOB,
+                EventPointcutType.BEFORE);
+    }
+
+    public static JobEvent yieldJobEventAfterCreation(AbstractJob source) {
+        return new JobEvent(source,
+                EventType.CREATION_EVENT,
+                EventSourceType.JOB,
+                EventPointcutType.AFTER);
+    }
+
+    public static JobEvent yieldJobEventBeforeRemoval(AbstractJob source) {
+        return new JobEvent(source,
+                EventType.REMOVAL_EVENT,
+                EventSourceType.JOB,
+                EventPointcutType.BEFORE);
+    }
+
+    public static JobEvent yieldJobEventAfterRemoval(AbstractJob source) {
+        return new JobEvent(source,
+                EventType.REMOVAL_EVENT,
+                EventSourceType.JOB,
+                EventPointcutType.AFTER);
+    }
+}
diff --git a/service/src/main/java/org/apache/griffin/core/event/JobEventHook.java b/service/src/main/java/org/apache/griffin/core/event/JobEventHook.java
new file mode 100644
index 0000000..5c95f3e
--- /dev/null
+++ b/service/src/main/java/org/apache/griffin/core/event/JobEventHook.java
@@ -0,0 +1,31 @@
+/*
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, 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.apache.griffin.core.event;
+
+import org.apache.griffin.core.exception.GriffinException;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration(value = "GriffinJobEventHook")
+public class JobEventHook implements GriffinHook {
+    @Override
+    public void onEvent(GriffinEvent event) throws GriffinException {
+        // This method needs to be reimplemented by event-consuming purpose
+    }
+}
diff --git a/service/src/main/java/org/apache/griffin/core/exception/GriffinException.java b/service/src/main/java/org/apache/griffin/core/exception/GriffinException.java
index db532ab..f1cdaba 100644
--- a/service/src/main/java/org/apache/griffin/core/exception/GriffinException.java
+++ b/service/src/main/java/org/apache/griffin/core/exception/GriffinException.java
@@ -60,4 +60,9 @@
         }
     }
 
+    public static class UnImplementedException extends GriffinException {
+        public UnImplementedException(String message) {
+            super(message);
+        }
+    }
 }
diff --git a/service/src/main/java/org/apache/griffin/core/job/JobServiceImpl.java b/service/src/main/java/org/apache/griffin/core/job/JobServiceImpl.java
index ac14461..4768efc 100644
--- a/service/src/main/java/org/apache/griffin/core/job/JobServiceImpl.java
+++ b/service/src/main/java/org/apache/griffin/core/job/JobServiceImpl.java
@@ -19,43 +19,12 @@
 
 package org.apache.griffin.core.job;
 
-import static java.util.TimeZone.getTimeZone;
-import static org.apache.griffin.core.config.EnvConfig.ENV_BATCH;
-import static org.apache.griffin.core.config.EnvConfig.ENV_STREAMING;
-import static org.apache.griffin.core.exception.GriffinExceptionMessage.INVALID_MEASURE_ID;
-import static org.apache.griffin.core.exception.GriffinExceptionMessage.JOB_ID_DOES_NOT_EXIST;
-import static org.apache.griffin.core.exception.GriffinExceptionMessage.JOB_NAME_DOES_NOT_EXIST;
-import static org.apache.griffin.core.exception.GriffinExceptionMessage.JOB_TYPE_DOES_NOT_SUPPORT;
-import static org.apache.griffin.core.exception.GriffinExceptionMessage.MEASURE_TYPE_DOES_NOT_SUPPORT;
-import static org.apache.griffin.core.exception.GriffinExceptionMessage.NO_SUCH_JOB_ACTION;
-import static org.apache.griffin.core.exception.GriffinExceptionMessage.QUARTZ_JOB_ALREADY_EXIST;
-import static org.apache.griffin.core.job.entity.LivySessionStates.State.BUSY;
-import static org.apache.griffin.core.job.entity.LivySessionStates.State.DEAD;
-import static org.apache.griffin.core.job.entity.LivySessionStates.State.IDLE;
-import static org.apache.griffin.core.job.entity.LivySessionStates.State.NOT_STARTED;
-import static org.apache.griffin.core.job.entity.LivySessionStates.State.RECOVERING;
-import static org.apache.griffin.core.job.entity.LivySessionStates.State.RUNNING;
-import static org.apache.griffin.core.job.entity.LivySessionStates.State.STARTING;
-import static org.apache.griffin.core.job.entity.LivySessionStates.State.UNKNOWN;
-import static org.apache.griffin.core.job.entity.LivySessionStates.isActive;
-import static org.apache.griffin.core.measure.entity.GriffinMeasure.ProcessType.BATCH;
-import static org.apache.griffin.core.measure.entity.GriffinMeasure.ProcessType.STREAMING;
-import static org.quartz.CronScheduleBuilder.cronSchedule;
-import static org.quartz.JobBuilder.newJob;
-import static org.quartz.JobKey.jobKey;
-import static org.quartz.SimpleScheduleBuilder.simpleSchedule;
-import static org.quartz.TriggerBuilder.newTrigger;
-import static org.quartz.TriggerKey.triggerKey;
-
 import com.fasterxml.jackson.core.type.TypeReference;
 
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.List;
-import java.util.TimeZone;
-
 import org.apache.commons.lang.StringUtils;
+import org.apache.griffin.core.event.GriffinEventManager;
 import org.apache.griffin.core.exception.GriffinException;
+import org.apache.griffin.core.event.JobEvent;
 import org.apache.griffin.core.job.entity.AbstractJob;
 import org.apache.griffin.core.job.entity.BatchJob;
 import org.apache.griffin.core.job.entity.JobHealth;
@@ -99,10 +68,43 @@
 import org.springframework.web.client.ResourceAccessException;
 import org.springframework.web.client.RestTemplate;
 
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.TimeZone;
+
+import static java.util.TimeZone.getTimeZone;
+import static org.apache.griffin.core.config.EnvConfig.ENV_BATCH;
+import static org.apache.griffin.core.config.EnvConfig.ENV_STREAMING;
+import static org.apache.griffin.core.exception.GriffinExceptionMessage.INVALID_MEASURE_ID;
+import static org.apache.griffin.core.exception.GriffinExceptionMessage.JOB_ID_DOES_NOT_EXIST;
+import static org.apache.griffin.core.exception.GriffinExceptionMessage.JOB_NAME_DOES_NOT_EXIST;
+import static org.apache.griffin.core.exception.GriffinExceptionMessage.JOB_TYPE_DOES_NOT_SUPPORT;
+import static org.apache.griffin.core.exception.GriffinExceptionMessage.MEASURE_TYPE_DOES_NOT_SUPPORT;
+import static org.apache.griffin.core.exception.GriffinExceptionMessage.NO_SUCH_JOB_ACTION;
+import static org.apache.griffin.core.exception.GriffinExceptionMessage.QUARTZ_JOB_ALREADY_EXIST;
+import static org.apache.griffin.core.job.entity.LivySessionStates.State.BUSY;
+import static org.apache.griffin.core.job.entity.LivySessionStates.State.DEAD;
+import static org.apache.griffin.core.job.entity.LivySessionStates.State.IDLE;
+import static org.apache.griffin.core.job.entity.LivySessionStates.State.NOT_STARTED;
+import static org.apache.griffin.core.job.entity.LivySessionStates.State.RECOVERING;
+import static org.apache.griffin.core.job.entity.LivySessionStates.State.RUNNING;
+import static org.apache.griffin.core.job.entity.LivySessionStates.State.STARTING;
+import static org.apache.griffin.core.job.entity.LivySessionStates.State.UNKNOWN;
+import static org.apache.griffin.core.job.entity.LivySessionStates.isActive;
+import static org.apache.griffin.core.measure.entity.GriffinMeasure.ProcessType.BATCH;
+import static org.apache.griffin.core.measure.entity.GriffinMeasure.ProcessType.STREAMING;
+import static org.quartz.CronScheduleBuilder.cronSchedule;
+import static org.quartz.JobBuilder.newJob;
+import static org.quartz.JobKey.jobKey;
+import static org.quartz.SimpleScheduleBuilder.simpleSchedule;
+import static org.quartz.TriggerBuilder.newTrigger;
+import static org.quartz.TriggerKey.triggerKey;
+
 @Service
 public class JobServiceImpl implements JobService {
     private static final Logger LOGGER = LoggerFactory
-            .getLogger(JobServiceImpl.class);
+        .getLogger(JobServiceImpl.class);
     public static final String GRIFFIN_JOB_ID = "griffinJobId";
     private static final int MAX_PAGE_SIZE = 1024;
     private static final int DEFAULT_PAGE_SIZE = 10;
@@ -127,6 +129,8 @@
     private BatchJobOperatorImpl batchJobOp;
     @Autowired
     private StreamingJobOperatorImpl streamingJobOp;
+    @Autowired
+    private GriffinEventManager eventManager;
 
     private RestTemplate restTemplate;
 
@@ -158,17 +162,22 @@
         } catch (SchedulerException e) {
             LOGGER.error("Failed to get RUNNING jobs.", e);
             throw new GriffinException
-                    .ServiceException("Failed to get RUNNING jobs.", e);
+                .ServiceException("Failed to get RUNNING jobs.", e);
         }
         return dataList;
     }
 
     @Override
     public AbstractJob addJob(AbstractJob job) throws Exception {
+        JobEvent jobEvent = JobEvent.yieldJobEventBeforeCreation(job);
+        eventManager.notifyListeners(jobEvent);
         Long measureId = job.getMeasureId();
         GriffinMeasure measure = getMeasureIfValid(measureId);
         JobOperator op = getJobOperator(measure.getProcessType());
-        return op.add(job, measure);
+        AbstractJob jobSaved = op.add(job, measure);
+        jobEvent = JobEvent.yieldJobEventAfterCreation(jobSaved);
+        eventManager.notifyListeners(jobEvent);
+        return jobSaved;
     }
 
     @Override
@@ -177,7 +186,7 @@
         if (job == null) {
             LOGGER.warn("Job id {} does not exist.", jobId);
             throw new GriffinException
-                    .NotFoundException(JOB_ID_DOES_NOT_EXIST);
+                .NotFoundException(JOB_ID_DOES_NOT_EXIST);
         }
         return job;
     }
@@ -198,7 +207,7 @@
     }
 
     private void doAction(String action, AbstractJob job, JobOperator op)
-            throws Exception {
+        throws Exception {
         switch (action) {
             case START:
                 op.start(job);
@@ -208,7 +217,7 @@
                 break;
             default:
                 throw new GriffinException
-                        .NotFoundException(NO_SUCH_JOB_ACTION);
+                    .NotFoundException(NO_SUCH_JOB_ACTION);
         }
     }
 
@@ -224,8 +233,12 @@
     public void deleteJob(Long jobId) throws SchedulerException {
         AbstractJob job = jobRepo.findByIdAndDeleted(jobId, false);
         validateJobExist(job);
+        JobEvent event = JobEvent.yieldJobEventBeforeRemoval(job);
+        eventManager.notifyListeners(event);
         JobOperator op = getJobOperator(job);
         op.delete(job);
+        event = JobEvent.yieldJobEventAfterRemoval(job);
+        eventManager.notifyListeners(event);
     }
 
     /**
@@ -239,31 +252,35 @@
         if (CollectionUtils.isEmpty(jobs)) {
             LOGGER.warn("There is no job with '{}' name.", name);
             throw new GriffinException
-                    .NotFoundException(JOB_NAME_DOES_NOT_EXIST);
+                .NotFoundException(JOB_NAME_DOES_NOT_EXIST);
         }
         for (AbstractJob job : jobs) {
+            JobEvent event = JobEvent.yieldJobEventBeforeRemoval(job);
+            eventManager.notifyListeners(event);
             JobOperator op = getJobOperator(job);
             op.delete(job);
+            event = JobEvent.yieldJobEventAfterRemoval(job);
+            eventManager.notifyListeners(event);
         }
     }
 
     @Override
     public List<JobInstanceBean> findInstancesOfJob(
-            Long jobId,
-            int page,
-            int size) {
+        Long jobId,
+        int page,
+        int size) {
         AbstractJob job = jobRepo.findByIdAndDeleted(jobId, false);
         if (job == null) {
             LOGGER.warn("Job id {} does not exist.", jobId);
             throw new GriffinException
-                    .NotFoundException(JOB_ID_DOES_NOT_EXIST);
+                .NotFoundException(JOB_ID_DOES_NOT_EXIST);
         }
         size = size > MAX_PAGE_SIZE ? MAX_PAGE_SIZE : size;
         size = size <= 0 ? DEFAULT_PAGE_SIZE : size;
         Pageable pageable = new PageRequest(page, size,
-                Sort.Direction.DESC, "tms");
+            Sort.Direction.DESC, "tms");
         List<JobInstanceBean> instances = instanceRepo.findByJobId(jobId,
-                pageable);
+            pageable);
         return updateState(instances);
     }
 
@@ -294,7 +311,7 @@
             } catch (SchedulerException e) {
                 LOGGER.error("Job schedule exception. {}", e);
                 throw new GriffinException
-                        .ServiceException("Fail to Get HealthInfo", e);
+                    .ServiceException("Fail to Get HealthInfo", e);
             }
 
         }
@@ -305,8 +322,8 @@
     public void deleteExpiredJobInstance() {
         Long timeMills = System.currentTimeMillis();
         List<JobInstanceBean> instances = instanceRepo
-                .findByExpireTmsLessThanEqual
-                        (timeMills);
+            .findByExpireTmsLessThanEqual
+                (timeMills);
         if (!batchJobOp.pauseJobInstances(instances)) {
             LOGGER.error("Pause job failure.");
             return;
@@ -329,7 +346,7 @@
             return streamingJobOp;
         }
         throw new GriffinException.BadRequestException
-                (JOB_TYPE_DOES_NOT_SUPPORT);
+            (JOB_TYPE_DOES_NOT_SUPPORT);
     }
 
     private JobOperator getJobOperator(ProcessType type) {
@@ -339,21 +356,21 @@
             return streamingJobOp;
         }
         throw new GriffinException.BadRequestException
-                (MEASURE_TYPE_DOES_NOT_SUPPORT);
+            (MEASURE_TYPE_DOES_NOT_SUPPORT);
     }
 
     TriggerKey getTriggerKeyIfValid(String qName, String qGroup) throws
-            SchedulerException {
+        SchedulerException {
         TriggerKey triggerKey = triggerKey(qName, qGroup);
         if (factory.getScheduler().checkExists(triggerKey)) {
             throw new GriffinException.ConflictException
-                    (QUARTZ_JOB_ALREADY_EXIST);
+                (QUARTZ_JOB_ALREADY_EXIST);
         }
         return triggerKey;
     }
 
     List<? extends Trigger> getTriggers(String name, String group) throws
-            SchedulerException {
+        SchedulerException {
         if (name == null || group == null) {
             return null;
         }
@@ -363,7 +380,7 @@
     }
 
     private JobState genJobState(AbstractJob job, String action) throws
-            SchedulerException {
+        SchedulerException {
         JobOperator op = getJobOperator(job);
         JobState state = op.getState(job, action);
         job.setJobState(state);
@@ -375,7 +392,7 @@
     }
 
     void addJob(TriggerKey tk, AbstractJob job, ProcessType type) throws
-            Exception {
+        Exception {
         JobDetail jobDetail = addJobDetail(tk, job);
         Trigger trigger = genTriggerInstance(tk, jobDetail, job, type);
         factory.getScheduler().scheduleJob(trigger);
@@ -405,34 +422,34 @@
 
     private GriffinMeasure getMeasureIfValid(Long measureId) {
         GriffinMeasure measure = measureRepo.findByIdAndDeleted(measureId,
-                false);
+            false);
         if (measure == null) {
             LOGGER.warn("The measure id {} isn't valid. Maybe it doesn't " +
-                            "exist or is external measure type.",
-                    measureId);
+                    "exist or is external measure type.",
+                measureId);
             throw new GriffinException.BadRequestException(INVALID_MEASURE_ID);
         }
         return measure;
     }
 
     private Trigger genTriggerInstance(TriggerKey tk, JobDetail jd, AbstractJob
-            job, ProcessType type) {
+        job, ProcessType type) {
         TriggerBuilder builder = newTrigger().withIdentity(tk).forJob(jd);
         if (type == BATCH) {
             TimeZone timeZone = getTimeZone(job.getTimeZone());
             return builder.withSchedule(cronSchedule(job.getCronExpression())
-                    .inTimeZone(timeZone)).build();
+                .inTimeZone(timeZone)).build();
         } else if (type == STREAMING) {
             return builder.startNow().withSchedule(simpleSchedule()
-                    .withRepeatCount(0)).build();
+                .withRepeatCount(0)).build();
         }
         throw new GriffinException.BadRequestException
-                (JOB_TYPE_DOES_NOT_SUPPORT);
+            (JOB_TYPE_DOES_NOT_SUPPORT);
 
     }
 
     private JobDetail addJobDetail(TriggerKey triggerKey, AbstractJob job)
-            throws SchedulerException {
+        throws SchedulerException {
         Scheduler scheduler = factory.getScheduler();
         JobKey jobKey = jobKey(triggerKey.getName(), triggerKey.getGroup());
         JobDetail jobDetail;
@@ -441,7 +458,7 @@
             jobDetail = scheduler.getJobDetail(jobKey);
         } else {
             jobDetail = newJob(JobInstance.class).storeDurably().withIdentity
-                    (jobKey).build();
+                (jobKey).build();
         }
         setJobDataMap(jobDetail, job);
         scheduler.addJob(jobDetail, isJobKeyExist);
@@ -462,9 +479,9 @@
      * @param measureId measure id
      */
     public void deleteJobsRelateToMeasure(Long measureId) throws
-            SchedulerException {
+        SchedulerException {
         List<AbstractJob> jobs = jobRepo.findByMeasureIdAndDeleted(measureId,
-                false);
+            false);
         if (CollectionUtils.isEmpty(jobs)) {
             LOGGER.info("Measure id {} has no related jobs.", measureId);
             return;
@@ -478,7 +495,7 @@
     @Scheduled(fixedDelayString = "${jobInstance.fixedDelay.in.milliseconds}")
     public void syncInstancesOfAllJobs() {
         LivySessionStates.State[] states = {STARTING, NOT_STARTED, RECOVERING,
-                IDLE, RUNNING, BUSY};
+            IDLE, RUNNING, BUSY};
         List<JobInstanceBean> beans = instanceRepo.findByActiveState(states);
         for (JobInstanceBean jobInstance : beans) {
             syncInstancesOfJob(jobInstance);
@@ -496,21 +513,21 @@
             return;
         }
         String uri = env.getProperty("livy.uri") + "/"
-                + instance.getSessionId();
+            + instance.getSessionId();
         TypeReference<HashMap<String, Object>> type =
-                new TypeReference<HashMap<String, Object>>() {
-                };
+            new TypeReference<HashMap<String, Object>>() {
+            };
         try {
             String resultStr = restTemplate.getForObject(uri, String.class);
             HashMap<String, Object> resultMap = JsonUtil.toEntity(resultStr,
-                    type);
+                type);
             setJobInstanceIdAndUri(instance, resultMap);
         } catch (ResourceAccessException e) {
             LOGGER.error("Your url may be wrong. Please check {}.\n {}", uri, e
-                    .getMessage());
+                .getMessage());
         } catch (HttpClientErrorException e) {
             LOGGER.warn("sessionId({}) appId({}) {}.", instance.getSessionId(),
-                    instance.getAppId(), e.getMessage());
+                instance.getAppId(), e.getMessage());
             setStateByYarn(instance, e);
         } catch (Exception e) {
             LOGGER.error(e.getMessage());
@@ -523,7 +540,7 @@
         if (!checkStatus(instance, e)) {
             int code = e.getStatusCode().value();
             boolean match = (code == 400 || code == 404)
-                    && instance.getAppId() != null;
+                && instance.getAppId() != null;
             //this means your url is correct,but your param is wrong or livy
             //session may be overdue.
             if (match) {
@@ -553,7 +570,7 @@
         // {id} not found',this means instance may not be scheduled for
         // a long time by spark for too many tasks. It may be dead.
         if (code == 404 && appId == null && (responseBody != null &&
-                responseBody.contains(sessionId.toString()))) {
+            responseBody.contains(sessionId.toString()))) {
             instance.setState(DEAD);
             instance.setDeleted(true);
             instanceRepo.save(instance);
@@ -564,7 +581,7 @@
 
     private void setStateByYarn(JobInstanceBean instance) {
         LOGGER.warn("Spark session {} may be overdue! " +
-                "Now we use yarn to update state.", instance.getSessionId());
+            "Now we use yarn to update state.", instance.getSessionId());
         String yarnUrl = env.getProperty("yarn.uri");
         boolean success = YarnNetUtil.update(yarnUrl, instance);
         if (!success) {
@@ -578,16 +595,16 @@
 
 
     private void setJobInstanceIdAndUri(JobInstanceBean instance, HashMap<String
-            , Object> resultMap) {
+        , Object> resultMap) {
         if (resultMap != null) {
             Object state = resultMap.get("state");
             Object appId = resultMap.get("appId");
             instance.setState(state == null ? null : LivySessionStates.State
-                    .valueOf(state.toString().toUpperCase
-                            ()));
+                .valueOf(state.toString().toUpperCase
+                    ()));
             instance.setAppId(appId == null ? null : appId.toString());
             instance.setAppUri(appId == null ? null : env
-                    .getProperty("yarn.uri") + " /cluster/app/ " + appId);
+                .getProperty("yarn.uri") + " /cluster/app/ " + appId);
             instanceRepo.save(instance);
         }
     }
@@ -595,9 +612,9 @@
     public Boolean isJobHealthy(Long jobId) {
         Pageable pageable = new PageRequest(0, 1, Sort.Direction.DESC, "tms");
         List<JobInstanceBean> instances = instanceRepo.findByJobId(jobId,
-                pageable);
+            pageable);
         return !CollectionUtils.isEmpty(instances) && LivySessionStates
-                .isHealthy(instances.get(0).getState());
+            .isHealthy(instances.get(0).getState());
     }
 
     @Override
diff --git a/service/src/main/resources/application.properties b/service/src/main/resources/application.properties
index 2e9c8f7..1c26319 100644
--- a/service/src/main/resources/application.properties
+++ b/service/src/main/resources/application.properties
@@ -62,3 +62,5 @@
 livy.uri=http://localhost:8998/batches
 # yarn url
 yarn.uri=http://localhost:8088
+# griffin event listener
+internal.event.listeners=GriffinJobEventHook
diff --git a/service/src/test/java/org/apache/griffin/core/job/EventServiceTest.java b/service/src/test/java/org/apache/griffin/core/job/EventServiceTest.java
new file mode 100644
index 0000000..2cbbd84
--- /dev/null
+++ b/service/src/test/java/org/apache/griffin/core/job/EventServiceTest.java
@@ -0,0 +1,107 @@
+/*
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, 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.apache.griffin.core.job;
+
+import static org.apache.griffin.core.util.EntityHelper.createGriffinMeasure;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.griffin.core.event.EventSourceType;
+import org.apache.griffin.core.event.EventType;
+import org.apache.griffin.core.event.GriffinEvent;
+import org.apache.griffin.core.event.GriffinHook;
+import org.apache.griffin.core.exception.GriffinException;
+import org.apache.griffin.core.job.entity.BatchJob;
+import org.apache.griffin.core.job.entity.JobDataSegment;
+import org.apache.griffin.core.measure.entity.GriffinMeasure;
+import org.apache.griffin.core.measure.entity.Measure;
+import org.apache.griffin.core.util.EntityHelper;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.orm.jpa.DataJpaTest;
+import org.springframework.boot.test.autoconfigure.orm.jpa.TestEntityManager;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.test.context.junit4.SpringRunner;
+
+@RunWith(SpringRunner.class)
+@DataJpaTest
+@ComponentScan("org.apache.griffin.core")
+public class EventServiceTest {
+    @Autowired
+    private JobService jobService;
+
+    @Autowired
+    private TestEntityManager entityManager;
+
+    @Autowired
+    private List<GriffinEvent> eventList;
+
+    @Before
+    public void setup() throws Exception {
+        entityManager.clear();
+        entityManager.flush();
+        setEntityManager();
+    }
+
+    @Test
+    public void testAddJobEvent() throws Exception {
+        BatchJob batch_Job = EntityHelper.createGriffinJob();
+        batch_Job.setCronExpression("0 0 12 * * ?");
+        batch_Job.setTimeZone("Asia/Shanghai");
+        JobDataSegment jds = new JobDataSegment();
+        jds.setAsTsBaseline(true);
+        jds.setDataConnectorName("target_name");
+        List jds_list = new ArrayList();
+        jds_list.add(jds);
+        batch_Job.setSegments(jds_list);
+        jobService.addJob(batch_Job);
+        Assert.assertEquals(2, eventList.size());
+        Assert.assertEquals(EventType.CREATION_EVENT, eventList.get(0).getType());
+        Assert.assertEquals(EventSourceType.JOB, eventList.get(1).getSourceType());
+    }
+
+    public void setEntityManager() throws Exception {
+        Measure measure1 = createGriffinMeasure("m1");
+        measure1.setOrganization("org1");
+        ((GriffinMeasure) measure1).setProcessType(GriffinMeasure.ProcessType.BATCH);
+        entityManager.persistAndFlush(measure1);
+    }
+
+    @Configuration(value = "GriffinTestJobEventHook")
+    public static class TestJobEventHook implements GriffinHook {
+        private List<GriffinEvent> eventList = new ArrayList<>();
+
+        @Override
+        public void onEvent(GriffinEvent event) throws GriffinException {
+            eventList.add(event);
+        }
+
+        @Bean
+        public List<GriffinEvent> getReceivedEvents() {
+            return eventList;
+        }
+    }
+}
diff --git a/service/src/test/resources/application.properties b/service/src/test/resources/application.properties
index 96d28dc..86d5316 100644
--- a/service/src/test/resources/application.properties
+++ b/service/src/test/resources/application.properties
@@ -6,9 +6,9 @@
 # to you under the Apache License, Version 2.0 (the
 # "License"); you may not use this file except in compliance
 # with the License.  You may obtain a copy of the License at
-# 
+#
 #   http://www.apache.org/licenses/LICENSE-2.0
-# 
+#
 # Unless required by applicable law or agreed to in writing,
 # software distributed under the License is distributed on an
 # "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
@@ -56,4 +56,6 @@
 elasticsearch.port=9200
 elasticsearch.scheme=http
 # elasticsearch.user = user
-# elasticsearch.password = password
\ No newline at end of file
+# elasticsearch.password = password
+# griffin event listener
+internal.event.listeners=GriffinJobEventHook,GriffinTestJobEventHook