• Java 连接 SqlServer工具类


    1.下载 server2008R2驱动jar包

    下载jar包

     http://www.microsoft.com/zh-cn/download/confirmation.aspx?id=21599

    2.代码实现

     1)实体:

    package entity;
    
    import java.io.Serializable;
    import java.util.Date;
    
    public class User implements Serializable{
        private int id;
        private String username;
        private String password;
        private Date createtime;
        public int getId() {
            return id;
        }
        public void setId(int id) {
            this.id = id;
        }
        public String getUsername() {
            return username;
        }
        public void setUsername(String username) {
            this.username = username;
        }
        public String getPassword() {
            return password;
        }
        public void setPassword(String password) {
            this.password = password;
        }
        public Date getCreatetime() {
            return createtime;
        }
        public void setCreatetime(Date createtime) {
            this.createtime = createtime;
        }
        public User(int id, String username, String password, Date createtime) {
            super();
            this.id = id;
            this.username = username;
            this.password = password;
            this.createtime = createtime;
        }
        
        public User(String username, String password, Date createtime) {
            super();
            this.username = username;
            this.password = password;
            this.createtime = createtime;
        }
        public User() {
            super();
        
        }
        @Override
        public String toString() {
            return "User [id=" + id + ", username=" + username + ", password="
                    + password + ", createtime=" + createtime + "]";
        }
        
    }

    2.dao

    package dao;
    
    
    import java.util.List;
    
    import entity.User;
    
    public interface UserDao {
        public void add(User u);
        
        public User getByUsername(String username);
        
        public void update(User u);
        
        public void delete(String username);
        
        public List<User> findAll();
    }

    3.ImplDao

    package daoImpl;
    
    import java.sql.Connection;
    import java.sql.PreparedStatement;
    import java.sql.ResultSet;
    import java.util.ArrayList;
    import java.util.Date;
    
    
    
    import java.util.List;
    
    import jdbcutil.JdbcUtil;
    import dao.UserDao;
    import entity.User;
    
    
    
    public class UserDaoImpl implements UserDao {
    
        @Override
        public void add(User u) {
            
            Connection con = null;
            PreparedStatement stmt = null;
            ResultSet rs = null;
            
            try {
                con = JdbcUtil.getConnection();
                String sql = "insert into [user](username,password,createtime) values(?,?,?)";
                stmt= con.prepareStatement(sql);
                stmt.setString(1, "test");
                stmt.setString(2,"123456");
                stmt.setDate(3, new java.sql.Date(u.getCreatetime().getTime()));
                stmt.executeUpdate();
                
            } catch (Exception e) {
                
                e.printStackTrace();
            }finally
            {
                JdbcUtil.close(rs, stmt, con);
            }
    
        }
    
        @Override
        public User getByUsername(String username) {
            
            Connection con = null;
            PreparedStatement stmt = null;
            ResultSet rs = null;
            
            try {
                con = JdbcUtil.getConnection();
                String sql = "select * from [user] where username=?";
                stmt = con.prepareStatement(sql);
                stmt.setString(1, username);
                rs = stmt.executeQuery();        
                while(rs.next())
                {
                    int id = rs.getInt("id");
                    String name = rs.getString("username");
                    String password = rs.getString("password");
                    Date time = rs.getDate("createtime");
                    
                    User u = new User(id,username,password,time);
                    
                    return u;
                    
                }
            } catch (Exception e) {
                
                e.printStackTrace();
            }
            finally
            {
                
                JdbcUtil.close(rs, stmt, con);            
            }
            return null;
        }
    
        @Override
        public void update(User u) {
            
            Connection con = null;
            PreparedStatement stmt = null;
            ResultSet rs = null;
            
            try {
                con = JdbcUtil.getConnection();
                
                String sql = "update [user] set password=? where username=?";
                
                stmt = con.prepareStatement(sql);
                
                stmt.setString(1, u.getPassword());
                
                stmt.setString(2, u.getUsername());
                
                stmt.executeUpdate();
                
            } catch (Exception e) {
                
                e.printStackTrace();
            }
            finally
            {
                
                JdbcUtil.close(rs, stmt, con);
            }
        }
    
        @Override
        public void delete(String username) {
            
            Connection con = null;
            PreparedStatement stmt = null;
            ResultSet rs = null;
            
            try {
                con = JdbcUtil.getConnection();
                
                String sql = "delete from [user] where username=?";
                
                stmt = con.prepareStatement(sql);
                
                stmt.setString(1,username);
            
                stmt.executeUpdate();
                
            } catch (Exception e) {
                
                e.printStackTrace();
            }
            finally
            {
                
                JdbcUtil.close(rs, stmt, con);
            }
        }
    
        @Override
        public List<User> findAll() {
            List<User> list = new ArrayList<User>();
            
            Connection con = null;
            PreparedStatement stmt = null;
            ResultSet rs = null;
            
            try {
                con = JdbcUtil.getConnection();
                String sql = "select * from [user]";
                
                stmt = con.prepareStatement(sql);
                
                rs = stmt.executeQuery();
                
                while(rs.next())
                {
                    User u = new User(rs.getInt("id"), rs.getString("username"),rs.getString("password"),rs.getDate("createtime"));
                    list.add(u);
                    
                }
                return list;
                
            } catch (Exception e) {
                
                e.printStackTrace();
            }
            finally
            {
                    JdbcUtil.close(rs, stmt, con);
                
            }
            
            return null;
        }
        
    
    
    }

    4.JDBC工具类

    package jdbcutil;
    
    import java.io.InputStream;
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import java.sql.Statement;
    import java.util.Properties;
    
    
    
    public class JdbcUtil {
        
        private static String className;
        private static String url;
        private static String user;
        private static String password;
        
        static
        {
            
            try {
                InputStream in = JdbcUtil.class.getClassLoader().getResourceAsStream("dbinfo.properties");
                
                Properties props = new Properties();
                props.load(in);
                
                className = props.getProperty("className");
                
                url = props.getProperty("url");
                
                user = props.getProperty("user");
                
                password = props.getProperty("password");
                
                //System.out.println(className);
                
                //System.out.println(url);
                
                //注册驱动
                Class.forName(className);
                
            } catch (Exception e) {
                
                e.printStackTrace();
            }
            
        }
        
        public static Connection getConnection() throws Exception
        {
            return DriverManager.getConnection(url, user, password);
            
        }
        
        public static void close(ResultSet rs, Statement stmt,Connection con)
        {
            
            if(rs!=null)
            {
                try {
                    rs.close();
                } catch (SQLException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                
                rs= null;
            }
            
            if(stmt!=null)
            {
                try {
                    stmt.close();
                } catch (SQLException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                
                stmt= null;
            }
            
            if(con!=null)
            {
                try {
                    con.close();
                } catch (SQLException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                
                con= null;
            }
        }
    }    

    5.用于测试SQLServer驱动是否正确

    package test;
    
    import java.sql.Connection;
    import java.sql.DriverManager;
    
    
    
    public class JdbcTest {
        public static void test()
        {
            Connection conn = null;
            try {
                Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
                
                //注意url中没有microsoft才能使用,网上增加了microsoft的会出现No suitable driver found for//jdbc:microsoft:sqlserver:……的错误
                //若安装多个实例时,要确认相应的port及实例名
                String url="jdbc:sqlserver://localhost:1433;DatabaseName=JavaTestDB";
                String user="sa";
                String password="123456";
                conn= DriverManager.getConnection(url,user,password);
                
                System.out.println("链接成功");
                
            } catch (Exception e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            finally
            {
                if(conn!=null)
                {
                    try {
                        conn.close();
                    } catch (Exception e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                    
                    conn = null;
                    
                }
                
            }
        
        }
    }

    备注: dbinfo.properties文件:

    6.添加SQLServer jar包 

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  • 原文地址:https://www.cnblogs.com/zoro-zero/p/4806788.html
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