1、原生jdbc连接oracle数据库简单介绍

一。jbdc的常用API
1.Connection:数据库的链接对象
2.statement:数据库sql执行对象
3.preparedStatment：sql的预编译处理对象，是statement子接口
4.resultset：返回查询的结果集

二。jdbc开发步骤
1.在项目中加入驱动jar包
2.写jdbc链接代码
注意：日期对象的处理。从结果集中获取时间是用getTimestamp(),得到的是Timestamp对象（时间戳）
Timestamp是util.Date的子类。他们之间的互相转换是：
util.Date = Timestamp直接转换
Timestamp = new TimeStamp(util.Date.getTime());

三。工厂模式
1.工厂类，专门用来生产某一个对象的实例

四。preparedStatment 预编译sql命令接口
1.会对sql语句进行编译检查，可以用参数占位符的方式编写sql语句
2.作用：比普通statement接口执行效率更高。可以防止sql注入的侵入

　　SQL实例：

 1 drop table user_info;
 2 drop table group_info;
 3 drop table contacts_info;
 4 
 5 select * from user_info
 6 select * from group_info
 7 select * from contacts_info
 8 
 9 delete from user_info;
10 delete from group_info;
11 
12 
13 --创建用户信息表
14 create table user_info(
15     user_id int identity(1,1) primary key,
16     user_name nvarchar(30) unique not null,
17     user_password nvarchar(30) not null
18     )
19     
20 --创建联系人群组信息表
21 create table group_info(
22     group_id int identity(1,1) primary key,
23     group_name nvarchar(30),
24     group_state nchar(3) default '可修改',
25     check(group_state in ('可修改','不可改')),
26     user_id int,
27     foreign key (user_id) references user_info(user_id)
28     )
29     
30 --创建联系人信息表
31 create table contacts_info(
32     con_id int identity(1,1) primary key,
33     con_name nvarchar(30) not null,
34     con_sex nchar(1) default '男',
35     check(con_sex in ('男','女')),
36     con_age int,
37     con_cellphone nvarchar(30),
38     con_telephone nvarchar(30),
39     con_birth datetime,
40     con_email nvarchar(30),
41     con_static nchar(3) default '未删除',
42     check(con_static in ('未删除','已删除')),
43     group_id int,
44     foreign key (group_id) references group_info(group_id)
45     )

java实例1：创建jdbc工厂类

　　jdbc.properties

jdbc.driver=oracle.jdbc.driver.OracleDriver
jdbc.url=jdbc:oracle:thin:@localhost:1521:orcl
jdbc.username=C##java06
jdbc.password=java123

    JDBCFactory.java类

 1 package com.demo1207;
 2 
 3 import java.io.IOException;
 4 import java.io.InputStream;
 5 import java.sql.Connection;
 6 import java.sql.DriverManager;
 7 import java.sql.ResultSet;
 8 import java.sql.SQLException;
 9 import java.sql.Statement;
10 import java.util.Properties;
11 
12 public class JDBCFactory {
13  //    private static final String DRIVER = "oracle.jdbc.driver.OracleDriver";
14 //    private static final String URL = "jdbc:oracle:thin:@localhost:1521:orcl";
15 //    private static final String USERNAME = "C##java06";
16 //    private static final String PASSWORD = "java123";
17 
18     static String DRIVER;
19     static String URL;
20     static String USERNAME;
21     static String PASSWORD;
22     static{
23         //只会在类第一次加载时被执行一次，适合做资源文件的读取
24         //加载数据库配置文件资源
25         Properties pro = new Properties();
26         //把资源读取成字节输入流
27         InputStream is = JDBCFactory.class.getResourceAsStream("jdbc.properties");
28         
29         try {
30             //通过资源对象加载字节输入流
31             pro.load(is);
32             //资源对象通过key来获取对应的文件中的值，注意：静态代码块只能使用静态属性
33             DRIVER = pro.getProperty("jdbc.driver");
34             URL = pro.getProperty("jdbc.url");
35             USERNAME = pro.getProperty("jdbc.username");
36             PASSWORD = pro.getProperty("jdbc.password");
37         } catch (IOException e) {
38             // TODO Auto-generated catch block
39             e.printStackTrace();
40         }
41     }
42     
43     /**
44      * 获取数据库链接
45      * @return 如果有异常则会返回null
46      */
47     public static Connection getConn(){
48         Connection conn = null;
49         try {
50             Class.forName(DRIVER);
51             conn = DriverManager.getConnection(URL, USERNAME, PASSWORD);
52         } catch (Exception e) {
53             e.printStackTrace();
54         }
55         return conn;
56     }
57     
58     public static void closeAll(Connection conn,Statement st,ResultSet rs){
59         if(conn!=null){
60             try {
61                 conn.close();
62             } catch (SQLException e) {
63                 e.printStackTrace();
64             }
65         }
66         if(st!=null){
67             try {
68                 st.close();
69             } catch (SQLException e) {
70                 e.printStackTrace();
71             }
72         }
73         if(rs!=null){
74             try {
75                 rs.close();
76             } catch (SQLException e) {
77                 // TODO Auto-generated catch block
78                 e.printStackTrace();
79             }
80         }
81     }
82 }

java实例2:调用工厂类

在java类中写一个Student对象，用来封装学员信息
查询学员信息表，将结果集封装到List<Student>
提示：学员对象的时间字段用util.Date. 每个属性都要封装

　　Student.java

 1 package com.demo1207;
 2 
 3 import java.util.Date;
 4 
 5 public class Student {
 6     private int student_id;
 7     private String student_name;
 8     private String student_sex;
 9     private int student_age;
10     private int class_id;
11     private Date birthday;
12     public int getStudent_id() {
13         return student_id;
14     }
15     public void setStudent_id(int student_id) {
16         this.student_id = student_id;
17     }
18     public String getStudent_name() {
19         return student_name;
20     }
21     public void setStudent_name(String student_name) {
22         this.student_name = student_name;
23     }
24     public String getStudent_sex() {
25         return student_sex;
26     }
27     public void setStudent_sex(String student_sex) {
28         this.student_sex = student_sex;
29     }
30     public int getStudent_age() {
31         return student_age;
32     }
33     public void setStudent_age(int student_age) {
34         this.student_age = student_age;
35     }
36     public int getClass_id() {
37         return class_id;
38     }
39     public void setClass_id(int class_id) {
40         this.class_id = class_id;
41     }
42     public Date getBirthday() {
43         return birthday;
44     }
45     public void setBirthday(Date birthday) {
46         this.birthday = birthday;
47     }
48     
49     
50 }

　　JdbcTest.java

 1 package com.demo1207;
 2 
 3 import java.sql.Connection;
 4 import java.sql.DriverManager;
 5 import java.sql.ResultSet;
 6 import java.sql.SQLException;
 7 import java.sql.Statement;
 8 import java.util.ArrayList;
 9 import java.util.List;
10 
11 public class JdbcTest {
12     public static void main(String[] args) {
13         Connection conn = null;
14         Statement st = null;
15         ResultSet rs = null;
16         try {
17             conn = JDBCFactory.getConn();
18             System.out.println(conn);
19             
20             //处理sql命令的对象
21             st = conn.createStatement();
22             
23             String sql = "insert into student_info values(sq_student.nextval,'叶挺',1,22,1,sysdate)";
24             //st来执行sql语句，注意executeUpdate是执行增删改的语句
25             st.executeUpdate(sql);
26             
27             //执行查询业务
28             String sql2 = "select * from student_info";
29             rs = st.executeQuery(sql2);
30             List<Student> list = new ArrayList<>();
31             while(rs.next()){
32                 Student stu = new Student();
33                 stu.setStudent_id(rs.getInt(1));
34                 stu.setStudent_name(rs.getString(2));
35                 stu.setStudent_sex(rs.getString(3));
36                 stu.setStudent_age(rs.getInt(4));
37                 stu.setClass_id(rs.getInt(5));
38                 stu.setBirthday(rs.getTimestamp(6));
39                 list.add(stu);
40                 System.out.print(rs.getInt(1)+"\t");
41                 System.out.print(rs.getString("student_name")+"\t");
42                 System.out.print(rs.getString(3)+"\t");
43                 System.out.print(rs.getInt(4)+"\t");
44                 System.out.print(rs.getInt(5)+"\t");
45                 System.out.println(rs.getTimestamp(6));
46             }
47         } catch (Exception e) {
48             e.printStackTrace();
49         } finally {
50             JDBCFactory.closeAll(conn, st, rs);
51         }
52     }
53 }

java实例3：调用jdbc工厂类来验证登录

PreparedDemo.java

 1 package com.demo1207;
 2 
 3 import java.sql.Connection;
 4 import java.sql.PreparedStatement;
 5 import java.sql.ResultSet;
 6 
 7 public class PreparedDemo {
 8     public static void main(String[] args) {
 9         Connection conn = null;
10         PreparedStatement ps = null;
11         ResultSet rs = null;
12         
13         try {
14             conn = JDBCFactory.getConn();
15             String sql = "select * from user_info where username=? and pass_word=?";
16             ps = conn.prepareStatement(sql);
17             //将参数占位符赋值
18             ps.setString(1, "张三");
19             ps.setString(2, "123456");
20             
21             //执行sql 和statement的执行方法一样
22             rs = ps.executeQuery();
23             if(rs.next()){
24                 System.out.println(rs.getString(2)+"登录成功");
25             }else{
26                 System.out.println("登录失败");
27             }
28         } catch (Exception e) {
29             e.printStackTrace();
30         } finally {
31             JDBCFactory.closeAll(conn, ps, rs);
32         }
33     }
34 }

java实例4：调用工厂类进行增删改查

 1 package com.demo1207;
 2 
 3 import java.sql.Connection;
 4 import java.sql.PreparedStatement;
 5 import java.sql.ResultSet;
 6 import java.sql.Timestamp;
 7 import java.util.Date;
 8 
 9 public class CRUDDemo {
10     Connection conn;
11     PreparedStatement ps;
12     ResultSet rs;
13     
14     public  void create(){
15         try {
16             conn = JDBCFactory.getConn();
17             
18             String sql = "insert into student_info values(sq_student.nextval,?,?,?,?,?)";
19             ps = conn.prepareStatement(sql);
20             
21             ps.setString(1, "田甜");
22             ps.setString(2, "2");
23             ps.setInt(3, 22);
24             ps.setInt(4, 1);
25             ps.setTimestamp(5, new Timestamp(new Date().getTime()));
26             ps.executeUpdate();
27             System.out.println("新增成功");
28         } catch (Exception e) {
29             e.printStackTrace();
30         } finally {
31             JDBCFactory.closeAll(conn, ps, rs);
32         }
33     }
34     
35     public void delete(){
36         try {
37             conn = JDBCFactory.getConn();
38             
39             String sql = "delete from student_info where student_id=?";
40             ps = conn.prepareStatement(sql);
41             
42             ps.setInt(1, 1);
43             ps.executeUpdate();
44             System.out.println("删除成功");
45         } catch (Exception e) {
46             e.printStackTrace();
47         } finally {
48             JDBCFactory.closeAll(conn, ps, rs);
49         }
50     }
51     
52     public void update(){
53         try {
54             conn = JDBCFactory.getConn();
55             
56             String sql = "update student_info set student_name=?,student_sex=?,student_age=?,class_id=?,birthday=? where student_id=?";
57             ps = conn.prepareStatement(sql);
58             
59             ps.setString(1, "哈哈");
60             ps.setString(2, "2");
61             ps.setInt(3, 28);
62             ps.setInt(4, 1);
63             ps.setTimestamp(5, new Timestamp(new Date().getTime()));
64             ps.setInt(6, 2);
65             ps.executeUpdate();
66             System.out.println("修改成功");
67         } catch (Exception e) {
68             e.printStackTrace();
69         } finally {
70             JDBCFactory.closeAll(conn, ps, rs);
71         }
72     }
73     
74     public void query(){
75         try {
76             conn = JDBCFactory.getConn();
77             
78             String sql = "select * from student_info";
79             ps = conn.prepareStatement(sql);
80             
81             rs = ps.executeQuery();
82             while(rs.next()){
83                 System.out.println();
84             }
85         } catch (Exception e) {
86             e.printStackTrace();
87         } finally {
88             JDBCFactory.closeAll(conn, ps, rs);
89         }
90     }
91 }

作业：

一。用户管理
1.用户注册：要求用户名不能重复
2.用户登录
二。联系人组群管理
1.用户新建联系人组群：每个用户注册时都会默认新建一个名字叫“我的联系人”这么一个组群，该组群不能修改，
                每个用户可以新建n个联系人组群。
2.用户修改联系组群：修改组群名字
3.用户删除组群：删除组群后，将该组的所有联系人移到默认组群“我的联系人”
三。联系人管理
1.用户新建联系人：需要指定联系人到哪个组群。联系人信息（姓名，年龄，性别，移动电话，固定电话，生日，邮箱）
2.用户修改联系人：可以修改联系人所有信息，包括组群
3.用户删除联系人：
4.查询联系人：
    a.按姓名模糊查询
    b.按组群查询
    c.按电话号码模糊查询