H2 Database Engine

H2 Database Engine

http://www.h2database.com/html/main.html

 

一個小型的database，可以跟著你的project跑，不用安裝一堆資料庫。

 

使用步驟：

 

1. JAR檔：c:\Program Files\H2\bin\h2.jar

 

2. web.xml設定：

    在web.xml加入下面的code，就可以使用http://localhost:8080/console連到它的console了。

	<!-- 
		H2-DB的設定
	 -->
	<listener>
		<listener-class>org.h2.server.web.DbStarter</listener-class>
	</listener>

	<context-param>
		<param-name>db.url</param-name>
		<!--
			<param-value>jdbc:h2:dbdata/test</param-value>會出現在eclipse\dbdata下面
		-->
		<!-- <param-value>jdbc:h2:/dbdata/test</param-value>會出現在d:\dbdata下面 -->
		<param-value>jdbc:h2:/workspace/TWM/H2Sample/dbdata/mycv</param-value>
	</context-param>
	<context-param>
		<param-name>db.user</param-name>
		<param-value>sa</param-value>
	</context-param>
	<context-param>
		<param-name>db.password</param-name>
		<param-value>sa</param-value>
	</context-param>
	<context-param>
		<param-name>db.tcpServer</param-name>
		<param-value>-tcpAllowOthers</param-value>
	</context-param>

	<servlet>
		<servlet-name>H2Console</servlet-name>
		<servlet-class>org.h2.server.web.WebServlet</servlet-class>
		<load-on-startup>1</load-on-startup>
	</servlet>

	<servlet-mapping>
		<servlet-name>H2Console</servlet-name>
		<url-pattern>/console/*</url-pattern>
	</servlet-mapping>

 3. Connection、JdbcDataSource and JdbcConnectionPool：

     根據官方的說法，其實是不需用到DataSource的，應為它用JDBC的方式取Connection已經很快了~~

	static private String url = "jdbc:h2:/workspace/TWM/H2Sample/dbdata/mycv";
	static private String user = "sa";
	static private String password = "sa";
	
	static private JdbcDataSource jdbcDataSource = null; 
	static private JdbcConnectionPool jdbcConnectionPool = null;
	static public Connection conn = null;
	
	static {
		logger.info("DBUtil init JdbcConnectionPool..");
		jdbcDataSource = new JdbcDataSource();
		jdbcDataSource.setURL(url);
		jdbcDataSource.setUser(user);
		jdbcDataSource.setPassword(password);
		jdbcConnectionPool = JdbcConnectionPool.create(jdbcDataSource);
		logger.info("DBUtil init JdbcConnectionPool success.");
	}
	
	/**
	 * get connection by data source
	 * @return current connection
	 * @throws SQLException
	 */
	static public Connection getConnection() throws Exception{
		if(conn == null){
			// Class.forName("org.h2.Driver");
			// conn = DriverManager.getConnection(url, user, password);
			
			conn = jdbcConnectionPool.getConnection();
		}
		return conn;
	}

 4. Hibernate.cfg.xml

<hibernate-configuration>
    <session-factory>
        <property name="hibernate.bytecode.use_reflection_optimizer">false</property>
        <property name="hibernate.connection.driver_class">org.h2.Driver</property>
        <property name="hibernate.connection.password">sa</property>
        <property name="hibernate.connection.url">jdbc:h2:/workspace/TWM/H2Sample/dbdata/mycv</property>
        <property name="hibernate.connection.username">sa</property>
        <property name="hibernate.dialect">org.hibernate.dialect.H2Dialect</property>
        
        <mapping resource="per/kirk/mycv/beans/Autobiography.hbm.xml" />
        <mapping resource="per/kirk/mycv/beans/Experience.hbm.xml" />
        <mapping resource="per/kirk/mycv/beans/Qualification.hbm.xml" />
        <mapping resource="per/kirk/mycv/beans/SchoolLevel.hbm.xml" />
        <mapping resource="per/kirk/mycv/beans/UserDetail.hbm.xml" />
    </session-factory>
</hibernate-configuration>

 

• 若是資料庫不存在，就會動態的建立一個，而帳號密碼就是第一次設定的那個。
  

• 若URL為jdbc:h2:~/test，~表示會將資料庫建立在你的HOME下面，像是c:\Documents and Settings\YOUR_NAME\