empire-db-examples/empire-db-example-vue/src/main/java/org/apache/empire/rest/app/SampleServiceApp.java - empire-db - Git at Google

 /*
  * 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.empire.rest.app;
 import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.SQLException;
 import java.util.HashMap;
 import java.util.LinkedList;
 import java.util.Locale;
 import java.util.Map;
 import java.util.Queue;
 import java.util.ResourceBundle;

 import javax.servlet.ServletContext;
 import javax.servlet.ServletContextEvent;
 import javax.servlet.ServletContextListener;

 import org.apache.empire.commons.StringUtils;
 import org.apache.empire.db.DBCommand;
 import org.apache.empire.db.DBContext;
 import org.apache.empire.db.DBRecord;
 import org.apache.empire.db.context.DBContextStatic;
 import org.apache.empire.dbms.DBMSHandler;
 import org.apache.empire.rest.service.Service;
 import org.apache.empire.vue.sample.db.SampleDB;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;

 public class SampleServiceApp
 {
     private static final Logger log = LoggerFactory.getLogger(SampleServiceApp.class);

     /**
      * Implementation of ServletContextListener which create the SampleServiceApp Singleton
      * @author doebele
      */
     public static class ContextListener implements ServletContextListener {

         @Override
         public void contextInitialized(ServletContextEvent sce) {

             System.out.println("ServletContextListener:contextInitialized");
             // check singleton
             if (app!=null)
                 throw new RuntimeException("FATAL: SampleServiceApp already created!");
             // create application
             ServletContext ctx = sce.getServletContext();
             app = new SampleServiceApp(ctx);
             // done
             log.debug("SampleServiceApp created sucessfully!");
         }

         @Override
         public void contextDestroyed(ServletContextEvent sce) {
             System.out.println("ServletContextListener:contextDestroyed");
         }
     }

     private static SampleServiceApp app;

     public static SampleServiceApp instance()
     {
         return app;
     }

     private SampleConfig config = new SampleConfig();

     private Map<Locale, ResourceTextResolver> textResolverMap = new HashMap<Locale, ResourceTextResolver>();

     protected SampleServiceApp(ServletContext ctx)
     {
         // Logging
         config.init(ctx.getRealPath("WEB-INF/config.xml"));

         String messageBundle ="lang.messages";
         textResolverMap.put(Locale.ENGLISH, new ResourceTextResolver(ResourceBundle.getBundle(messageBundle, Locale.ENGLISH)));
         textResolverMap.put(Locale.GERMAN,  new ResourceTextResolver(ResourceBundle.getBundle(messageBundle, Locale.GERMAN)));

         // get connection
         Connection conn = getJDBCConnection(ctx);
         try {
             // DB
             DBMSHandler dbms = getDBMSHandler(config.getDatabaseProvider(), conn);
             DBContext context = new DBContextStatic(dbms, conn);
             SampleDB db = initDatabase(ctx, context);
             // Add to context
             ctx.setAttribute(Service.Consts.ATTRIBUTE_DB, db);
             // sce.getServletContext().setAttribute(MobileImportServiceConsts.ATTRIBUTE_DATASOURCE, ds);
             // sce.getServletContext().setAttribute(MobileImportServiceConsts.ATTRIBUTE_CONFIG, config);
         } finally {
             releaseConnection(conn, true);
         }
     }

     public TextResolver getTextResolver(Locale locale) {
         TextResolver tr = textResolverMap.get(locale);
         return (tr!=null ? tr : textResolverMap.get(Locale.ENGLISH));
     }

     /**
      * Creates an Empire-db DatabaseDriver for the given provider and applies dbms specific configuration
      */
     private DBMSHandler getDBMSHandler(String provider, Connection conn)
     {
         try
         {   // Get Driver Class Name
             String dbmsHandlerClass = config.getDbmsHandlerClass();
             if (StringUtils.isEmpty(dbmsHandlerClass))
                 throw new RuntimeException("Configuration error: Element 'dbmsHandlerClass' not found in node 'properties-"+provider+"'");

             // Create dbms
             DBMSHandler dbms = (DBMSHandler) Class.forName(dbmsHandlerClass).newInstance();

             // Configure dbms
             config.readProperties(dbms, "properties-"+provider, "dbmsHandlerProperties");

             // done
             return dbms;

         } catch (Exception e)
         {   // catch any checked exception and forward it
             e.printStackTrace();
             throw new RuntimeException(e);
         }
     }

     /*
      * Our own simple Connection pool
      */
     private final Queue<Connection> connPool = new LinkedList<Connection>();

     /*
      * getJDBCConnection
      */
     public Connection getJDBCConnection(ServletContext appContext)
     {
         Connection conn = connPool.poll();
         if (conn!=null)
             return conn;

         // Establish a new database connection
         String jdbcURL = config.getJdbcURL();
         if (jdbcURL.indexOf("file:") > 0)
             jdbcURL = StringUtils.replace(jdbcURL, "file:", "file:" + appContext.getRealPath("/"));
         // Connect
         log.info("Connecting to Database'" + jdbcURL + "' / User=" + config.getJdbcUser());
         try
         { // Connect to the database
             Class.forName(config.getJdbcClass()).newInstance();
             conn = DriverManager.getConnection(jdbcURL, config.getJdbcUser(), config.getJdbcPwd());
             log.info("Connected successfully");
             // set the AutoCommit to false this session. You must commit
             // explicitly now
             conn.setAutoCommit(false);
             log.info("AutoCommit is " + conn.getAutoCommit());
             return conn;
         }
         catch (Exception e)
         {
             log.error("Failed to connect directly to '" + config.getJdbcURL() + "' / User=" + config.getJdbcUser());
             log.error(e.toString());
             throw new RuntimeException(e);
         }
     }

     public void releaseConnection(Connection conn, boolean commit) {
         // release connection
         try
         { // release connection
             if (conn == null)
             {
                 return;
             }
             // Commit or rollback connection depending on the exit code
             if (commit)
             { // success: commit all changes
                 conn.commit();
                 log.debug("REQUEST commited.");
             }
             else
             { // failure: rollback all changes
                 conn.rollback();
                 log.debug("REQUEST rolled back.");
             }
             // close connection / return to pool
             // conn.close();
             connPool.add(conn);
         }
         catch (SQLException e)
         {
             log.error("Error releasing connection", e);
             throw new RuntimeException(e);
         }
     }


     // ********************* private *********************

     private SampleDB initDatabase(ServletContext ctx, DBContext context) {
         SampleDB db = new SampleDB();
         // Open Database (and create if not existing)
         DBMSHandler dbms = context.getDbms();
         log.info("Opening database '{}' using handler '{}'", db.getClass().getSimpleName(), dbms.getClass().getSimpleName());
         db.open(context);
         // check if database was just created
         DBCommand cmd = context.createCommand();
         cmd.select(db.EMPLOYEES.count());
         if (context.getUtils().querySingleInt(cmd)==0)
         {   // Populate Database
             populateDatabase(db, context);
         }
         return db;
     }

     private static void populateDatabase(SampleDB db, DBContext context) {
         // Insert Sample Departments
         insertDepartmentSampleRecord(db, context, "Procurement", "ITTK");
         int idDevDep = insertDepartmentSampleRecord(db, context, "Development", "ITTK");
         int idSalDep = insertDepartmentSampleRecord(db, context, "Sales", "ITTK");
         // Insert Sample Employees
         insertEmployeeSampleRecord(db, context, "Mr.", "Eugen", "Miller", "M", idDevDep);
         insertEmployeeSampleRecord(db, context, "Mr.", "Max", "Mc. Callahan", "M", idDevDep);
         insertEmployeeSampleRecord(db, context, "Mrs.", "Anna", "Smith", "F", idSalDep);
         // Commit
         context.commit();
     }

     private static int insertDepartmentSampleRecord(SampleDB db, DBContext context, String department_name, String businessUnit) {
         // Insert a Department
         DBRecord rec = new DBRecord(context, db.DEPARTMENTS);
         rec.create();
         rec.set(db.DEPARTMENTS.NAME, department_name);
         rec.set(db.DEPARTMENTS.BUSINESS_UNIT, businessUnit);
         try {
             rec.update();
         } catch (Exception e) {
             log.error(e.getLocalizedMessage());
             return 0;
         }
         // Return Department ID
         return rec.getInt(db.DEPARTMENTS.ID);
     }

     /*
      * Insert a person
      */
     private static int insertEmployeeSampleRecord(SampleDB db, DBContext context, String salutation, String firstName, String lastName, String gender, int depID) {
         // Insert an Employee
         DBRecord rec = new DBRecord(context, db.EMPLOYEES);
         rec.create();
         rec.set(db.EMPLOYEES.SALUTATION, salutation);
         rec.set(db.EMPLOYEES.FIRST_NAME, firstName);
         rec.set(db.EMPLOYEES.LAST_NAME, lastName);
         rec.set(db.EMPLOYEES.GENDER, gender);
         rec.set(db.EMPLOYEES.DEPARTMENT_ID, depID);
         try {
             rec.update();
         } catch (Exception e) {
             log.error(e.getLocalizedMessage());
             return 0;
         }
         // Return Employee ID
         return rec.getInt(db.EMPLOYEES.ID);
     }

     /*
     private void initLogging() {

         // Init Logging
         ConsoleAppender consoleAppender = new ConsoleAppender();
         String pattern = "%-5p [%d{yyyy/MM/dd HH:mm}]: %m at %l %n";
         consoleAppender.setLayout(new PatternLayout(pattern));
         consoleAppender.activateOptions();

         org.apache.log4j.Logger.getRootLogger().addAppender(consoleAppender);
         org.apache.log4j.Logger.getRootLogger().setLevel(Level.ALL);

         Level loglevel = Level.DEBUG;
         log.info("Setting LogLevel to {}", loglevel);

         // RootLogger
         org.apache.log4j.Logger.getRootLogger().setLevel(Level.INFO);

         // Empire-db Logs
         org.apache.log4j.Logger empireLog = org.apache.log4j.Logger.getLogger("org.apache.empire.db.DBDatabase");
         empireLog.setLevel(loglevel);

         // Vue.js Sample
         org.apache.log4j.Logger miLog = org.apache.log4j.Logger.getLogger("org.apache.empire.rest");
         miLog.setLevel(loglevel);
     }
     */

 }
	/*
	* 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.empire.rest.app;
	import java.sql.Connection;
	import java.sql.DriverManager;
	import java.sql.SQLException;
	import java.util.HashMap;
	import java.util.LinkedList;
	import java.util.Locale;
	import java.util.Map;
	import java.util.Queue;
	import java.util.ResourceBundle;

	import javax.servlet.ServletContext;
	import javax.servlet.ServletContextEvent;
	import javax.servlet.ServletContextListener;

	import org.apache.empire.commons.StringUtils;
	import org.apache.empire.db.DBCommand;
	import org.apache.empire.db.DBContext;
	import org.apache.empire.db.DBRecord;
	import org.apache.empire.db.context.DBContextStatic;
	import org.apache.empire.dbms.DBMSHandler;
	import org.apache.empire.rest.service.Service;
	import org.apache.empire.vue.sample.db.SampleDB;
	import org.slf4j.Logger;
	import org.slf4j.LoggerFactory;

	public class SampleServiceApp
	{
	private static final Logger log = LoggerFactory.getLogger(SampleServiceApp.class);

	/**
	* Implementation of ServletContextListener which create the SampleServiceApp Singleton
	* @author doebele
	*/
	public static class ContextListener implements ServletContextListener {

	@Override
	public void contextInitialized(ServletContextEvent sce) {

	System.out.println("ServletContextListener:contextInitialized");
	// check singleton
	if (app!=null)
	throw new RuntimeException("FATAL: SampleServiceApp already created!");
	// create application
	ServletContext ctx = sce.getServletContext();
	app = new SampleServiceApp(ctx);
	// done
	log.debug("SampleServiceApp created sucessfully!");
	}

	@Override
	public void contextDestroyed(ServletContextEvent sce) {
	System.out.println("ServletContextListener:contextDestroyed");
	}
	}

	private static SampleServiceApp app;

	public static SampleServiceApp instance()
	{
	return app;
	}

	private SampleConfig config = new SampleConfig();

	private Map<Locale, ResourceTextResolver> textResolverMap = new HashMap<Locale, ResourceTextResolver>();

	protected SampleServiceApp(ServletContext ctx)
	{
	// Logging
	config.init(ctx.getRealPath("WEB-INF/config.xml"));

	String messageBundle ="lang.messages";
	textResolverMap.put(Locale.ENGLISH, new ResourceTextResolver(ResourceBundle.getBundle(messageBundle, Locale.ENGLISH)));
	textResolverMap.put(Locale.GERMAN, new ResourceTextResolver(ResourceBundle.getBundle(messageBundle, Locale.GERMAN)));

	// get connection
	Connection conn = getJDBCConnection(ctx);
	try {
	// DB
	DBMSHandler dbms = getDBMSHandler(config.getDatabaseProvider(), conn);
	DBContext context = new DBContextStatic(dbms, conn);
	SampleDB db = initDatabase(ctx, context);
	// Add to context
	ctx.setAttribute(Service.Consts.ATTRIBUTE_DB, db);
	// sce.getServletContext().setAttribute(MobileImportServiceConsts.ATTRIBUTE_DATASOURCE, ds);
	// sce.getServletContext().setAttribute(MobileImportServiceConsts.ATTRIBUTE_CONFIG, config);
	} finally {
	releaseConnection(conn, true);
	}
	}

	public TextResolver getTextResolver(Locale locale) {
	TextResolver tr = textResolverMap.get(locale);
	return (tr!=null ? tr : textResolverMap.get(Locale.ENGLISH));
	}

	/**
	* Creates an Empire-db DatabaseDriver for the given provider and applies dbms specific configuration
	*/
	private DBMSHandler getDBMSHandler(String provider, Connection conn)
	{
	try
	{ // Get Driver Class Name
	String dbmsHandlerClass = config.getDbmsHandlerClass();
	if (StringUtils.isEmpty(dbmsHandlerClass))
	throw new RuntimeException("Configuration error: Element 'dbmsHandlerClass' not found in node 'properties-"+provider+"'");

	// Create dbms
	DBMSHandler dbms = (DBMSHandler) Class.forName(dbmsHandlerClass).newInstance();

	// Configure dbms
	config.readProperties(dbms, "properties-"+provider, "dbmsHandlerProperties");

	// done
	return dbms;

	} catch (Exception e)
	{ // catch any checked exception and forward it
	e.printStackTrace();
	throw new RuntimeException(e);
	}
	}

	/*
	* Our own simple Connection pool
	*/
	private final Queue<Connection> connPool = new LinkedList<Connection>();

	/*
	* getJDBCConnection
	*/
	public Connection getJDBCConnection(ServletContext appContext)
	{
	Connection conn = connPool.poll();
	if (conn!=null)
	return conn;

	// Establish a new database connection
	String jdbcURL = config.getJdbcURL();
	if (jdbcURL.indexOf("file:") > 0)
	jdbcURL = StringUtils.replace(jdbcURL, "file:", "file:" + appContext.getRealPath("/"));
	// Connect
	log.info("Connecting to Database'" + jdbcURL + "' / User=" + config.getJdbcUser());
	try
	{ // Connect to the database
	Class.forName(config.getJdbcClass()).newInstance();
	conn = DriverManager.getConnection(jdbcURL, config.getJdbcUser(), config.getJdbcPwd());
	log.info("Connected successfully");
	// set the AutoCommit to false this session. You must commit
	// explicitly now
	conn.setAutoCommit(false);
	log.info("AutoCommit is " + conn.getAutoCommit());
	return conn;
	}
	catch (Exception e)
	{
	log.error("Failed to connect directly to '" + config.getJdbcURL() + "' / User=" + config.getJdbcUser());
	log.error(e.toString());
	throw new RuntimeException(e);
	}
	}

	public void releaseConnection(Connection conn, boolean commit) {
	// release connection
	try
	{ // release connection
	if (conn == null)
	{
	return;
	}
	// Commit or rollback connection depending on the exit code
	if (commit)
	{ // success: commit all changes
	conn.commit();
	log.debug("REQUEST commited.");
	}
	else
	{ // failure: rollback all changes
	conn.rollback();
	log.debug("REQUEST rolled back.");
	}
	// close connection / return to pool
	// conn.close();
	connPool.add(conn);
	}
	catch (SQLException e)
	{
	log.error("Error releasing connection", e);
	throw new RuntimeException(e);
	}
	}


	// ******************* private *******************

	private SampleDB initDatabase(ServletContext ctx, DBContext context) {
	SampleDB db = new SampleDB();
	// Open Database (and create if not existing)
	DBMSHandler dbms = context.getDbms();
	log.info("Opening database '{}' using handler '{}'", db.getClass().getSimpleName(), dbms.getClass().getSimpleName());
	db.open(context);
	// check if database was just created
	DBCommand cmd = context.createCommand();
	cmd.select(db.EMPLOYEES.count());
	if (context.getUtils().querySingleInt(cmd)==0)
	{ // Populate Database
	populateDatabase(db, context);
	}
	return db;
	}

	private static void populateDatabase(SampleDB db, DBContext context) {
	// Insert Sample Departments
	insertDepartmentSampleRecord(db, context, "Procurement", "ITTK");
	int idDevDep = insertDepartmentSampleRecord(db, context, "Development", "ITTK");
	int idSalDep = insertDepartmentSampleRecord(db, context, "Sales", "ITTK");
	// Insert Sample Employees
	insertEmployeeSampleRecord(db, context, "Mr.", "Eugen", "Miller", "M", idDevDep);
	insertEmployeeSampleRecord(db, context, "Mr.", "Max", "Mc. Callahan", "M", idDevDep);
	insertEmployeeSampleRecord(db, context, "Mrs.", "Anna", "Smith", "F", idSalDep);
	// Commit
	context.commit();
	}

	private static int insertDepartmentSampleRecord(SampleDB db, DBContext context, String department_name, String businessUnit) {
	// Insert a Department
	DBRecord rec = new DBRecord(context, db.DEPARTMENTS);
	rec.create();
	rec.set(db.DEPARTMENTS.NAME, department_name);
	rec.set(db.DEPARTMENTS.BUSINESS_UNIT, businessUnit);
	try {
	rec.update();
	} catch (Exception e) {
	log.error(e.getLocalizedMessage());
	return 0;
	}
	// Return Department ID
	return rec.getInt(db.DEPARTMENTS.ID);
	}

	/*
	* Insert a person
	*/
	private static int insertEmployeeSampleRecord(SampleDB db, DBContext context, String salutation, String firstName, String lastName, String gender, int depID) {
	// Insert an Employee
	DBRecord rec = new DBRecord(context, db.EMPLOYEES);
	rec.create();
	rec.set(db.EMPLOYEES.SALUTATION, salutation);
	rec.set(db.EMPLOYEES.FIRST_NAME, firstName);
	rec.set(db.EMPLOYEES.LAST_NAME, lastName);
	rec.set(db.EMPLOYEES.GENDER, gender);
	rec.set(db.EMPLOYEES.DEPARTMENT_ID, depID);
	try {
	rec.update();
	} catch (Exception e) {
	log.error(e.getLocalizedMessage());
	return 0;
	}
	// Return Employee ID
	return rec.getInt(db.EMPLOYEES.ID);
	}

	/*
	private void initLogging() {

	// Init Logging
	ConsoleAppender consoleAppender = new ConsoleAppender();
	String pattern = "%-5p [%d{yyyy/MM/dd HH:mm}]: %m at %l %n";
	consoleAppender.setLayout(new PatternLayout(pattern));
	consoleAppender.activateOptions();

	org.apache.log4j.Logger.getRootLogger().addAppender(consoleAppender);
	org.apache.log4j.Logger.getRootLogger().setLevel(Level.ALL);

	Level loglevel = Level.DEBUG;
	log.info("Setting LogLevel to {}", loglevel);

	// RootLogger
	org.apache.log4j.Logger.getRootLogger().setLevel(Level.INFO);

	// Empire-db Logs
	org.apache.log4j.Logger empireLog = org.apache.log4j.Logger.getLogger("org.apache.empire.db.DBDatabase");
	empireLog.setLevel(loglevel);

	// Vue.js Sample
	org.apache.log4j.Logger miLog = org.apache.log4j.Logger.getLogger("org.apache.empire.rest");
	miLog.setLevel(loglevel);
	}
	*/

	}