1、数据库配置文件 database.properties
#jdbc properties
db.driver=oracle.jdbc.driver.OracleDriver
db.url=jdbc:oracle:thin:@172.16.11.81:1521:orcl
db.username=kpchen
db.password=kpchen
2、加载数据库配置文件JDBC.java
package com.ilfy.lbjn.utils;
import java.io.InputStream;
import java.util.Properties;
public class JDBC {
/**
* jdbc Properties
*/
private static Properties pro;
/**
* db user
*/
private String user;
/**
* db pass
*/
private String pass;
/**
* db driver
*/
private String driver;
/**
* db url
*/
private String url;
public JDBC() {
loadFile();
this.url = pro.getProperty("db.url");
this.pass = pro.getProperty("db.password");
this.driver = pro.getProperty("db.driver");
this.user = pro.getProperty("db.username");
}
/**
* 加载数据库配置文件 如果没有配置文件将使用默认值
*/
private void loadFile() {
if (pro == null) {
try {
pro = new Properties();
Class cls = JDBC.class;
ClassLoader cl = cls.getClassLoader();
InputStream in = cl.getResourceAsStream("database.properties");
pro.load(in);
} catch (Exception e) {
e.printStackTrace();
pro.put("db.driver", "org.gjt.mm.mysql.Driver");
pro.put("db.url", "jdbc:mysql://201.45.67.165:3306/login");
pro.put("db.username", "root");
pro.put("db.password", "root");
}
}
}
public String getUser() {
return user;
}
public String getPass() {
return pass;
}
public String getDriver() {
return driver;
}
public String getUrl() {
return url;
}
public String getProV(String key) {
return pro.getProperty(key);
}
}
3、封装增删改查 DBUtil.java
package com.ilfy.lbjn.utils;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import com.sun.rowset.CachedRowSetImpl;
public class DBUtil {
/**
* 数据库配置信息
*/
private static JDBC jdbc = new JDBC();
/**
* 数据库连接
*/
private Connection conn;
public DBUtil() {
conn = getConnection();
}
// 注册驱动
static {
try {
Class.forName(jdbc.getDriver());
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
}
/**
* 插入数据
*
* @param sql
* @param params
* @return
*/
public int insert(String sql, Object... params) {
return executeUpdate(sql, params);
}
/**
* 更新数据
*
* @param sql
* @param params
* @return
*/
public int update(String sql, Object... params) {
return executeUpdate(sql, params);
}
/**
* 删除数据
*
* @param sql
* @param params
* @return
*/
public int delete(String sql, Object... params) {
return executeUpdate(sql, params);
}
/**
* 执行DDL DML
*
* @param conn
* @param sql
* @return
*/
public int executeUpdate(String sql, Object... params) {
int rlt = 0;
try {
PreparedStatement pst = null;
pst = conn.prepareStatement(sql);
putParams(pst, params);
rlt = pst.executeUpdate();
pst.close();
} catch (SQLException e) {
e.printStackTrace();
}
return rlt;
}
/**
* 执行查询语句
*
* @param conn
* @param sql
* @return
*/
public CachedRowSetImpl query(String sql, Object... params) {
CachedRowSetImpl rowset = null;
PreparedStatement pst = null;
try {
pst = conn.prepareStatement(sql);
putParams(pst, params);
ResultSet rs = pst.executeQuery();
rowset = new CachedRowSetImpl();
rowset.populate(rs);
rs.close();
pst.close();
} catch (SQLException e) {
e.printStackTrace();
}
return rowset;
}
/**
* 获取数据库连接
*
* @return
*/
public Connection getConnection() {
Connection conn = null;
try {
conn = DriverManager.getConnection(jdbc.getUrl(), jdbc.getUser(),
jdbc.getPass());
} catch (SQLException e) {
e.printStackTrace();
}
return conn;
}
/**
* 往预编译语句中放置参数
*
* @param pst
* @param params
* []
* @throws SQLException
*/
private void putParams(PreparedStatement pst, Object... params)
throws SQLException {
if (params != null) {
for (int i = 0; i < params.length; i++) {
pst.setObject(i + 1, params[i]);
}
}
}
/**
* 关闭数据库链接
*/
public void close() {
if (this.conn != null) {
try {
this.conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
4、使用工具类DBUtil对数据库进行增删改查操作
package com.ilfy.lbjn.dao;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import com.ilfy.lbjn.pojo.User;
import com.ilfy.lbjn.utils.DBUtil;
import com.sun.rowset.CachedRowSetImpl;
/**
* @desc: lbjn
* @author: Administrator
* @createTime: 2014年11月10日 上午11:11:48
* @history:
* @version: v1.0
*/
public class UserDao {
/**
* @author: kpchen
* @createTime: 2014年11月10日 下午8:22:26
* @history:
* @return List
*/
public List findAllUsers() {
List userLists = new ArrayList();
DBUtil dbUtil = null;
User user = null;
CachedRowSetImpl rs = null;
String sql = "select * from tb_user";
try {
dbUtil = new DBUtil();
rs = dbUtil.query(sql);
while (rs.next()) {
user = new User(rs.getInt("USERID"), rs.getString("USERNAME"),
rs.getString("PASSWORD"), rs.getInt("ROLE"));
userLists.add(user);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
rs.close();
dbUtil.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
return userLists;
}
/**
* @author: kpchen
* @createTime: 2014年11月10日 下午8:22:20
* @history:
* @param id
* void
*/
public void delUser(String id) {
DBUtil dbUtil = null;
String sql = "delete from tb_user where userId=" + id;
try {
dbUtil = new DBUtil();
dbUtil.delete(sql);
} catch (Exception e) {
e.printStackTrace();
} finally {
dbUtil.close();
}
}
/**
* @author: kpchen
* @createTime: 2014年11月10日 下午8:40:26
* @history:
* @param user
* void
*/
public void addUser(User user) {
DBUtil dbUtil = null;
String sql = "insert into tb_user(userId,userName,password,role)values(?,?,?,?)";
Object[] obj = { user.getUserId(), user.getUserName(),
user.getPassword(), user.getRole() };
try {
dbUtil = new DBUtil();
dbUtil.insert(sql, obj);
} catch (Exception e) {
e.printStackTrace();
} finally {
dbUtil.close();
}
}
/**
* @author: kpchen
* @createTime: 2014年11月10日 下午8:48:02
* @history:
* @param id
* @return User
*/
public User getUserById(String id) {
DBUtil dbUtil = null;
User user = null;
CachedRowSetImpl rs = null;
String sql = "select * from tb_user where userId=" + id;
try {
dbUtil = new DBUtil();
rs = dbUtil.query(sql);
if (rs.next()) {
user = new User(rs.getInt("USERID"), rs.getString("USERNAME"),
rs.getString("PASSWORD"), rs.getInt("ROLE"));
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
rs.close();
dbUtil.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
return user;
}
/**
* @author: kpchen
* @createTime: 2014年11月10日 下午8:55:10
* @history:
* @param user
* void
*/
public void updateUser(User user) {
DBUtil dbUtil = null;
String sql = "update tb_user set userName=?, password=? ,role=? where userId = ?";
Object[] obj = { user.getUserName(), user.getPassword(),
user.getRole(), user.getUserId() };
try {
dbUtil = new DBUtil();
dbUtil.update(sql, obj);
} catch (Exception e) {
e.printStackTrace();
} finally {
dbUtil.close();
}
}
/**
* @author: kpchen
* @createTime: 2014年11月10日 下午9:18:30
* @history:
* @param where1
* @return List
*/
public List findUsersByUserName(String where1) {
List userLists = new ArrayList();
DBUtil dbUtil = null;
User user = null;
CachedRowSetImpl rs = null;
String sql = "select * from tb_user where 1=1 " + where1;
try {
dbUtil = new DBUtil();
rs = dbUtil.query(sql);
while (rs.next()) {
user = new User(rs.getInt("USERID"), rs.getString("USERNAME"),
rs.getString("PASSWORD"), rs.getInt("ROLE"));
userLists.add(user);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
rs.close();
dbUtil.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
return userLists;
}
}
5、源码：http://pan.baidu.com/s/14KoJc
