/*
 * 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.flink.runtime.messages.checkpoint;

import org.apache.flink.api.common.JobID;
import org.apache.flink.runtime.checkpoint.CheckpointException;
import org.apache.flink.runtime.executiongraph.ExecutionAttemptID;
import org.apache.flink.util.SerializedThrowable;

/**
 * This message is sent from the {@link org.apache.flink.runtime.taskexecutor.TaskExecutor} to the
 * {@link org.apache.flink.runtime.jobmaster.JobMaster} to tell the checkpoint coordinator
 * that a checkpoint request could not be heeded. This can happen if a Task is already in
 * RUNNING state but is internally not yet ready to perform checkpoints.
 */
public class DeclineCheckpoint extends AbstractCheckpointMessage implements java.io.Serializable {

	private static final long serialVersionUID = 2094094662279578953L;

	/** The reason why the checkpoint was declined. */
	private final Throwable reason;

	public DeclineCheckpoint(JobID job, ExecutionAttemptID taskExecutionId, long checkpointId) {
		this(job, taskExecutionId, checkpointId, null);
	}

	public DeclineCheckpoint(JobID job, ExecutionAttemptID taskExecutionId, long checkpointId, Throwable reason) {
		super(job, taskExecutionId, checkpointId);

		if (reason == null || reason instanceof CheckpointException) {
			this.reason = reason;
		} else {
			// some other exception. replace with a serialized throwable, to be on the safe side
			this.reason = new SerializedThrowable(reason);
		}
	}

	// --------------------------------------------------------------------------------------------

	/**
	 * Gets the reason why the checkpoint was declined.
	 *
	 * @return The reason why the checkpoint was declined
	 */
	public Throwable getReason() {
		return reason;
	}

	// --------------------------------------------------------------------------------------------

	@Override
	public String toString() {
		return String.format("Declined Checkpoint %d for (%s/%s): %s",
				getCheckpointId(), getJob(), getTaskExecutionId(), reason);
	}
}

@@ -901,72 +901,8 @@
 ID;%0A
-import org.apache.flink.runtime.checkpoint.CheckpointException;%0A
 impo
@@ -1015,16 +1015,51 @@
 wable;%0A%0A
+import javax.annotation.Nullable;%0A%0A
 /**%0A * T
@@ -1632,16 +1632,27 @@
 ned. */%0A
+%09@Nullable%0A
 %09private
@@ -1658,16 +1658,26 @@
 e final 
+Serialized
 Throwabl
@@ -1926,16 +1926,26 @@
 pointId,
+ @Nullable
  Throwab
@@ -2007,110 +2007,8 @@
 );%0A%0A
-%09%09if (reason == null %7C%7C reason instanceof CheckpointException) %7B%0A%09%09%09this.reason = reason;%0A%09%09%7D else %7B%0A%09
 %09%09//
@@ -2092,17 +2092,16 @@
  side%0A%09%09
-%09
 this.rea
@@ -2105,16 +2105,40 @@
 reason =
+ reason == null ? null :
  new Ser
@@ -2167,12 +2167,8 @@
 n);%0A
-%09%09%7D%0A
 %09%7D%0A%0A
@@ -2395,16 +2395,26 @@
 %09public 
+Serialized
 Throwabl

Make sure that CheckpointException are also serialized in DeclineCheckpoint.