首先，最基本的连接方式：
private String url = "jdbc:odbc:Driver={SQL Server};Server=DELL-PC;Database=MedicalData";private String user = "sa";private String password = "netlab";private Connection conn;Class.forName("sun.jdbc.odbc.JdbcOdbcDriver").newInstance();conn = DriverManager.getConnection(url, user, password);PreparedStatement partnames=conn.prepareStatement(sql);rs=partnames.executeQuery();Statement partnames=conn.createStatement();partnames.executeUpdate(sql);遇到问题：[Microsoft][ODBC SQL Server Driver]连接占线导致另一个 hstmt查了很多文章以后，感觉应该是由于短时间大量访问，导致没有释放资源，如rs，statement，conn等
这是查到了连接池 ，数据库连接池：查到了链接 这篇帖子的四楼方法，如下：
在util包中新建两个文件，一个是DataSourceFactory.java,另一个是databaseresource.properties配置文件，还有几个jar包，commons-dbcp-1.2.1.jar，commons-pool-1.3.jar，msbase.jar，mssqlserver.jar，msutil.jar，这5个jar包自己去网上下载下来
DataSourceFactory.java的内容如下
package util;import org.apache.commons.dbcp.*;import java.sql.*;import java.util.*;public class DataSourceFactory {private static String PROPERTIES_FILE = "/util/databaseresource.properties";private static DataSourceFactory instance = null;private BasicDataSource ds1;private DataSourceFactory() {Properties prop = new Properties();try {prop.load(this.getClass().getResourceAsStream(PROPERTIES_FILE));ds1 = (BasicDataSource)BasicDataSourceFactory.createDataSource(prop);} catch (Exception e) {e.printStackTrace();} }public static DataSourceFactory getInstance() {if(instance == null) {instance = new DataSourceFactory();}return instance;}public Connection getConnection() {Connection conn = null;try {conn = ds1.getConnection();} catch (Exception e) {e.printStackTrace();return null;}return conn;}}databaseresource.properties中的内容如下：（去除//之后的注释）driverClassName=com.microsoft.jdbc.sqlserver.SQLServerDriverurl=jdbc:microsoft:sqlserver://127.0.0.1:1433;DatabaseName=friend//friend为数据库名username=sa//数据库连接用户名password=null//数据库连接密码defaultAutoCommit=true//是否自动提交事务maxActive=10//连接池最大连接数弄好后在程序中用Connectionconn=DataSourceFactory.getInstance().getConnection();就可以等到数据库连接了
于是有了我的代码：
如下：
package com.k.sqlsever;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;import util.DataSourceFactory;public class SQLSeverLink {private String url = "jdbc:odbc:Driver={SQL Server};Server=DELL-PC;Database=MedicalData";private String user = "sa";private String password = "netlab";private Connection conn;public void link(){try {//Class.forName("sun.jdbc.odbc.JdbcOdbcDriver").newInstance();//conn = DriverManager.getConnection(url, user, password);conn = DataSourceFactory.getInstance().getConnection();} catch (Exception e) {// TODO: handle exceptione.printStackTrace();}}public void closeLink(){if(conn!=null)try {conn.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}public ResultSet select(String sql){ResultSet rs= null;try {PreparedStatement partnames=conn.prepareStatement(sql);rs=partnames.executeQuery();} catch (Exception e) {// TODO: handle exceptione.printStackTrace();}return rs;}public void update(String sql){try {Statement partnames=conn.createStatement();partnames.executeUpdate(sql);System.out.println("update success!");} catch (Exception e) {// TODO: handle exceptione.printStackTrace();}} /*** @param args*/ public static void main(String[] args) {// TODO Auto-generated method stubtry {Connection conn = DataSourceFactory.getInstance().getConnection();PreparedStatement partnames=conn.prepareStatement("SELECT * FROM dbo.MS_CHK_ALL WHERE id=1");ResultSet rs=partnames.executeQuery();while(rs.next()){String Data=rs.getString("chk_code");System.out.println(Data);}} catch ( Exception e) {// TODO Auto-generated catch blocke.printStackTrace();} }}这次又出现了新的问题，运行一小会以后，
[Microsoft][SQLServer 2000 Driver for JDBC]Error establishing socket.
我估计还是老问题，资源未释放
忍无可忍，笨方法： 每处理100条以后，，断开连接，重连数据库。sleep 100ms 再继续进行
if(i%100==0){serverLink.closeLink();serverLink.link();try {Thread.sleep(100);} catch (InterruptedException e) {// TODO Auto-generated catch blocke.printStackTrace();}}
辽远或偏僻的地方，而会常常想起这一次的旅行，想起那座山，那个城，那些人……
