Druid DBUtils ORM 封裝

package com.msi.druid;

import java.io.IOException; import java.io.InputStream; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.List; import java.util.Properties; import javax.sql.DataSource; import org.apache.commons.dbutils.QueryRunner; import org.apache.commons.dbutils.handlers.BeanListHandler; import com.alibaba.druid.pool.DruidDataSource; import com.alibaba.druid.pool.DruidDataSourceFactory; import com.alibaba.druid.pool.DruidPooledConnection; import com.msi.model.User;

public class DBHelper {

private static DBHelper dbHlper = null;
private static DruidDataSource druidDataSource;
private DataSource dataSource;
private QueryRunner runner = null;

public static DBHelper getInstance() {
	if (dbHlper == null) {
		dbHlper = new DBHelper();
	}
	return dbHlper;
}

static {
	Properties properties = loadProperties("db_server.properties");
	try {
		druidDataSource = (DruidDataSource) DruidDataSourceFactory
				.createDataSource(properties);
	} catch (Exception e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	}
}

public DruidDataSource getDruidDataSource() {
	return druidDataSource;
}

// 當不支持的時候,顯式調用Connection
public DruidPooledConnection getConnection() throws SQLException {
	return druidDataSource.getConnection();
}

public DataSource getDataSource() {
	this.dataSource = DBHelper.getInstance().getDruidDataSource();
	return dataSource;
}

public static Properties loadProperties(String fileName) {
	// TODO Auto-generated method stub
	Properties p = new Properties();

	// 方法1獲取配置
	// InputStream inStream =
	// DBHelper.class.getClass().getResourceAsStream("/db_dang.properties");
	InputStream inStream = null;
	try {

// 獲取配置的第二種方式 // String path = DBHelper.class.getClassLoader().getResource("\") // .getPath(); // path = new File(path).getParent(); // String profilepath = path + File.separator + fileName; // System.out.println("file ==="+profilepath); // inStream = new FileInputStream(new File(profilepath));

inStream = DBHelper.class.getClass().getResourceAsStream("/"+fileName);
		p.load(inStream);
	} catch (IOException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	} finally {
		try {
			if (inStream != null) {
				inStream.close();
			}
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	return p;
}

public QueryRunner initRunner() {
	this.dataSource = DBHelper.getInstance().getDataSource();
	if (this.dataSource != null) {
		this.runner = new QueryRunner(this.dataSource);
	}
	return runner;
}

public QueryRunner getRunner() {
	return initRunner();
}

public static void main(String[] args) throws SQLException {
	// TODO Auto-generated method stub
	List<User> userList = DBHelper
			.getInstance()
			.getRunner()
			.query("select * from t_user",
					new BeanListHandler<User>(User.class));
	for (int i = 0; i < userList.size(); i++) {
		System.out.print(userList.get(i) + "\r\n");
	}

	DruidPooledConnection conn = DBHelper.getInstance().getConnection();
	Statement stmt = conn.createStatement();
	ResultSet rs = stmt.executeQuery("select * from t_user");
	User user = null;
	while (rs.next()) {
		user = new User();
		user.setUserName(rs.getString("userName"));
		System.err.println(user.getUserName());
	}
}

}

配置以下 driverClassName=com.mysql.jdbc.Driver url=jdbc:mysql://localhost:3306/db_diary username=root password=yan filters=stat initialSize=2 maxActive=300 maxWait=60000 timeBetweenEvictionRunsMillis=60000 minEvictableIdleTimeMillis=300000 validationQuery=SELECT 1 testWhileIdle=true testOnBorrow=false testOnReturn=false poolPreparedStatements=true maxPoolPreparedStatementPerConnectionSize=200

WebXml中配置監控功能

<!-- 啓用Web監控統計功能須要在Web應用的web.xml中加入這個Servlet聲明 -->

<servlet>
	<servlet-name>DruidStatView</servlet-name>
	<servlet-class>com.alibaba.druid.support.http.StatViewServlet</servlet-class>
</servlet>
<servlet>
	<description>This is the description of my J2EE component</description>
	<display-name>This is the display name of my J2EE component</display-name>
	<servlet-name>DruidServlet</servlet-name>
	<servlet-class>com.msi.servlet.DruidServlet</servlet-class>
</servlet>

<servlet-mapping>
	<servlet-name>DruidStatView</servlet-name>
	<url-pattern>/druid/*</url-pattern>
</servlet-mapping>