[整理]Java连接数据库的几种方法

JDBC硬编码连接

import java.sql.Connection;import java.sql.DriverManager;import java.sql.SQLException;public class JDBCConn {public static final String DRIVER = "com.microsoft.sqlserver.jdbc.SQLServerDriver";public static final String URL = "jdbc:sqlserver://localhost:1433;DatabaseName=books";public static final String USER = "sa";public static final String PWD = "ok";private Connection conn = null;public Connection getConn() {try {Class.forName(DRIVER);conn = DriverManager.getConnection(URL,USER,PWD);} catch (ClassNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}return conn;}}

 

读取propperties配置文件连接

1.创建读取配置文件的类

 import java.io.IOException;import java.io.InputStream;import java.util.Properties;/** * 单列类：获取属性文件 * @author macau */public class Env extends Properties {/** * 构造方法 */private Env() {InputStream is = (InputStream) this.getClass().getResourceAsStream("/db.properties");//创建输出流try {load(is);//读取流is.close();} catch (IOException e) {e.printStackTrace();}}private static Env instance;//当前类实例/** * 获得当前实例 * @return */public static Env getInstance() {if (instance == null) {makeInstance();}return instance;}/** * 创建当前类实例 */private static synchronized void makeInstance() {if (instance == null) {instance = new Env();}}}

2.通过读取配置文件的类获取数据库连接参数

 import java.sql.Connection;import java.sql.DriverManager;import java.sql.SQLException;public class PropConn {private String driver = Env.getInstance().getProperty("driver");private String url = Env.getInstance().getProperty("url");private String user = Env.getInstance().getProperty("user");private String pwd = Env.getInstance().getProperty("pwd");private Connection conn = null;public Connection getConn(){try {Class.forName(driver);conn = DriverManager.getConnection(url,user,pwd);} catch (ClassNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}return conn;}}

 

配置JNDI获取

1.在Tomcat安装目录的conf目录下的context.xml文件的<Context/>标记中添加配置

<Resource name="jdbc/books" auth="Container" type="javax.sql.DataSource"maxActive="1000" maxIdel="30" maxWait="10000"username="sa" password="ok"driverClassName="com.microsoft.sqlserver.jdbc.SQLServerDriver"url="jdbc:sqlserver://localhost:1433;DatabaseName=books" />

2.编码获取数据库连接

import java.sql.Connection;import java.sql.SQLException;import javax.naming.Context;import javax.naming.InitialContext;import javax.naming.NamingException;import javax.sql.DataSource;public class JNDIConn {private Connection conn = null;public Connection getConn() {try {Context context = new InitialContext();DataSource source = (DataSource) context.lookup("java:comp/env/jdbc/books");conn = source.getConnection();} catch (NamingException e) {e.printStackTrace();} catch (SQLException e) {e.printStackTrace();}return conn;}}