/*
 * Copyright 2012-2015 the original author or authors.
 *
 * Licensed 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.springframework.boot.context.embedded.undertow;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.Date;
import java.util.LinkedHashMap;
import java.util.Map;

import io.undertow.servlet.UndertowServletLogger;
import io.undertow.servlet.api.SessionPersistenceManager;

/**
 * {@link SessionPersistenceManager} that stores session information in a file.
 *
 * @author Phillip Webb
 * @since 1.3.0
 */
public class FileSessionPersistence implements SessionPersistenceManager {

	private final File dir;

	public FileSessionPersistence(File dir) {
		this.dir = dir;
	}

	@Override
	public void persistSessions(String deploymentName,
			Map<String, PersistentSession> sessionData) {
		try {
			save(sessionData, getSessionFile(deploymentName));
		}
		catch (Exception ex) {
			UndertowServletLogger.ROOT_LOGGER.failedToPersistSessions(ex);
		}
	}

	private void save(Map<String, PersistentSession> sessionData, File file)
			throws IOException {
		ObjectOutputStream stream = new ObjectOutputStream(new FileOutputStream(file));
		try {
			save(sessionData, stream);
		}
		finally {
			stream.close();
		}
	}

	private void save(Map<String, PersistentSession> sessionData,
			ObjectOutputStream stream) throws IOException {
		Map<String, Serializable> session = new LinkedHashMap<String, Serializable>();
		for (Map.Entry<String, PersistentSession> entry : sessionData.entrySet()) {
			session.put(entry.getKey(),
					new SerializablePersistentSession(entry.getValue()));
		}
		stream.writeObject(session);
	}

	@Override
	public Map<String, PersistentSession> loadSessionAttributes(String deploymentName,
			final ClassLoader classLoader) {
		try {
			File file = getSessionFile(deploymentName);
			if (file.exists()) {
				return load(file);
			}
		}
		catch (Exception ex) {
			UndertowServletLogger.ROOT_LOGGER.failedtoLoadPersistentSessions(ex);
		}
		return null;
	}

	private Map<String, PersistentSession> load(File file)
			throws IOException, ClassNotFoundException {
		ObjectInputStream stream = new ObjectInputStream(new FileInputStream(file));
		try {
			return load(stream);
		}
		finally {
			stream.close();
		}
	}

	private Map<String, PersistentSession> load(ObjectInputStream stream)
			throws ClassNotFoundException, IOException {
		Map<String, SerializablePersistentSession> session = readSession(stream);
		long time = System.currentTimeMillis();
		Map<String, PersistentSession> result = new LinkedHashMap<String, PersistentSession>();
		for (Map.Entry<String, SerializablePersistentSession> entry : session
				.entrySet()) {
			PersistentSession entrySession = entry.getValue().getPersistentSession();
			if (entrySession.getExpiration().getTime() > time) {
				result.put(entry.getKey(), entrySession);
			}
		}
		return result;
	}

	@SuppressWarnings("unchecked")
	private Map<String, SerializablePersistentSession> readSession(
			ObjectInputStream stream) throws ClassNotFoundException, IOException {
		return ((Map<String, SerializablePersistentSession>) stream.readObject());
	}

	private File getSessionFile(String deploymentName) {
		if (!this.dir.exists()) {
			this.dir.mkdirs();
		}
		return new File(this.dir, deploymentName + ".session");
	}

	@Override
	public void clear(String deploymentName) {
		getSessionFile(deploymentName).delete();
	}

	/**
	 * Session data in a serializable form.
	 */
	static class SerializablePersistentSession implements Serializable {

		private static final long serialVersionUID = 0L;

		private final Date expiration;

		private final Map<String, Object> sessionData;

		SerializablePersistentSession(PersistentSession session) {
			this.expiration = session.getExpiration();
			this.sessionData = new LinkedHashMap<String, Object>(
					session.getSessionData());
		}

		public PersistentSession getPersistentSession() {
			return new PersistentSession(this.expiration, this.sessionData);
		}

	}

}

@@ -1075,16 +1075,80 @@
 nager;%0A%0A
+import org.springframework.core.ConfigurableObjectInputStream;%0A%0A
 /**%0A * %7B
@@ -2607,16 +2607,29 @@
 oad(file
+, classLoader
 );%0A%09%09%09%7D%0A
@@ -2799,32 +2799,57 @@
 %3E load(File file
+, ClassLoader classLoader
 )%0A%09%09%09throws IOEx
@@ -2911,24 +2911,36 @@
 tream = new 
+Configurable
 ObjectInputS
@@ -2937,32 +2937,37 @@
 jectInputStream(
+%0A%09%09%09%09
 new FileInputStr
@@ -2967,32 +2967,45 @@
 nputStream(file)
+, classLoader
 );%0A%09%09try %7B%0A%09%09%09re

Fix undertow session persistence with spring-boot-devtools