一、Statement接口
作用：用于执行静态 SQL 语句并返回它所生成结果的对象。
1. 创建数据库连接类及相册实体，代码如下：
1 package com.learn.jdbc.util;
2
3 import java.sql.Connection;
4 import java.sql.DriverManager;
5 import java.sql.PreparedStatement;
6 import java.sql.Statement;
7
8 /**
9 * 封装数据库连接类
10 * @author Administrator
11 *
12 */
13 public class DbUtil {
14 // 数据库连接
15 private static String dbUrl = "jdbc:mysql://localhost:3306/yizhuangxiu?useUnicode=true&characterEncoding=utf-8";
16 // 用户名
17 private static String dbUserName = "root";
18 // 密码
19 private static String dbUserPwd = "123456";
20 // 驱动名
21 private static String jdbcName = "com.mysql.jdbc.Driver";
22
23 /**
24 * 连接数据库
25 * @return
26 * @throws Exception
27 */
28 public Connection getCon() throws Exception{
29 Class.forName(jdbcName);
30 Connection con = DriverManager.getConnection(dbUrl, dbUserName, dbUserPwd);
31 return con;
32 }
33
34 /**
35 * 关闭连接
36 * @throws Exception
37 */
38 public void close(Statement stmt,Connection con) throws Exception{
39 if(stmt != null){
40 stmt.close();
41 if(con != null){
42 con.close();
43 }
44 }
45 }
46
47 /**
48 * 关闭连接
49 * @throws Exception
50 */
51 public void close(PreparedStatement pstmt,Connection con) throws Exception{
52 if(pstmt != null){
53 pstmt.close();
54 if(con != null){
55 con.close();
56 }
57 }
58 }
59
60
61 }
1 package com.learn.jdbc.model;
2
3 import java.io.File;
4
5 /**
6 * 相册模型
7 * @author Administrator
8 *
9 */
10 public class Album {
11
12 private int id;
13 private String name;
14 private int uid;
15 private long time;
16
17 private File content;
18 private File pic;
19
20 public Album(String name, int uid, long time) {
21 this.name = name;
22 this.uid = uid;
23 this.time = time;
24 }
25
26
27
28 public Album(int id, String name, int uid, long time) {
29 this.id = id;
30 this.name = name;
31 this.uid = uid;
32 this.time = time;
33 }
34
35 public Album(String name, int uid, long time, File content, File pic) {
36 super();
37 this.name = name;
38 this.uid = uid;
39 this.time = time;
40 this.content = content;
41 this.pic = pic;
42 }
43
44 public int getId() {
45 return id;
46 }
47
48 public void setId(int id) {
49 this.id = id;
50 }
51
52 public String getName() {
53 return name;
54 }
55
56 public void setName(String name) {
57 this.name = name;
58 }
59
60 public int getUid() {
61 return uid;
62 }
63
64 public void setUid(int uid) {
65 this.uid = uid;
66 }
67
68 public long getTime() {
69 return time;
70 }
71
72 public void setTime(long time) {
73 this.time = time;
74 }
75
76
77
78 public File getContent() {
79 return content;
80 }
81
82
83
84 public void setContent(File content) {
85 this.content = content;
86 }
87
88
89
90 public File getPic() {
91 return pic;
92 }
93
94
95
96 public void setPic(File pic) {
97 this.pic = pic;
98 }
99
100
101
102 @Override
103 public String toString() {
104 return "["+this.id+","+this.name+","+this.uid+","+this.time+"]";
105 }
106
107
108
109
110
111 }
2. 实现数据增加、修改、删除
1 package com.learn.jdbc.chap03;
2
3 import java.sql.Connection;
4 import java.sql.Statement;
5
6 import com.learn.jdbc.model.Album;
7 import com.learn.jdbc.util.DbUtil;
8
9 public class Demo3 {
10 private static DbUtil dbUtil=new DbUtil();
11
12 /**
13 * 添加相册-----用面向对象思想封装
14 * @param ab
15 * @return
16 * @throws Exception
17 */
18 private static int addInfo2(Album ab) throws Exception{
19 Connection con = dbUtil.getCon();
20 String sql = "insert into sp_album values (null,‘"+ab.getName()+"‘,"+ab.getUid()+","+ab.getTime()+")";
21 Statement stmt = con.createStatement();
22 int result=stmt.executeUpdate(sql);
23 dbUtil.close(stmt, con);
24 return result;
25 }
26
27 /**
28 * 添加相册-----普通封装
29 * @param name
30 * @param uid
31 * @param time
32 * @return
33 * @throws Exception
34 */
35 private static int addInfo(String name,int uid,long time) throws Exception{
36 Connection con = dbUtil.getCon();
37 String sql = "insert into sp_album values (null,‘"+name+"‘,"+uid+","+time+")";
38 Statement stmt = con.createStatement();
39 int result=stmt.executeUpdate(sql);
40 dbUtil.close(stmt, con);
41 return result;
42 }
43
44 public static void main(String[] args) throws Exception{
45 /*int result = addInfo("李四",8,System.currentTimeMillis());
46 if(result>0){
47 System.out.println("数据插入成功！");
48 }else{
49 System.out.println("数据插入失败！");
50 }*/
51
52 int result1 = addInfo2(new Album("呵呵",7,System.currentTimeMillis()));
53 if(result1>0){
54 System.out.println("数据插入成功！");
55 }else{
56 System.out.println("数据插入失败！");
57 }
58 }
59 }
1 package com.learn.jdbc.chap03;
2
3 import java.sql.Connection;
4 import java.sql.Statement;
5
6 import com.learn.jdbc.model.Album;
7 import com.learn.jdbc.util.DbUtil;
8
9 public class Demo4 {
10 private static DbUtil dbUtil = new DbUtil();
11
12 /**
13 * 更新相册
14 * @param ab
15 * @return
16 * @throws Exception
17 */
18 private static int updateInfo(Album ab) throws Exception {
19 Connection con = dbUtil.getCon();
20 String sql = "update sp_album set name=‘" + ab.getName() + "‘,uid="
21 + ab.getUid() + ",add_time=" + ab.getTime() + " where id="
22 + ab.getId();
23 Statement stmt = con.createStatement();
24 int result = stmt.executeUpdate(sql);
25 dbUtil.close(stmt, con);
26 return result;
27 }
28
29 public static void main(String[] args) throws Exception {
30 int result1 = updateInfo(new Album(12,"呵呵1", 6, System.currentTimeMillis()));
31 if (result1 > 0) {
32 System.out.println("数据修改成功！");
33 } else {
34 System.out.println("数据修改失败！");
35 }
36 }
37 }
1 package com.learn.jdbc.chap03;
2
3 import java.sql.Connection;
4 import java.sql.Statement;
5
6 import com.learn.jdbc.model.Album;
7 import com.learn.jdbc.util.DbUtil;
8
9 public class Demo5 {
10 private static DbUtil dbUtil = new DbUtil();
11 /**
12 * 删除数据
13 * @param id
14 * @return
15 * @throws Exception
16 */
17 private static int deleteInfo(int id) throws Exception{
18 Connection con = dbUtil.getCon();
19 String sql = "delete from sp_album where id="+id;
20 Statement stmt = con.createStatement();
21 int result = stmt.executeUpdate(sql);
22 dbUtil.close(stmt, con);
23 return result;
24 }
25
26 public static void main(String[] args) throws Exception {
27 int result1 = deleteInfo(13);
28 if (result1 > 0) {
29 System.out.println("数据删除成功！");
30 } else {
31 System.out.println("数据删除失败！");
32 }
33 }
34 }
所用到的表结构
CREATE TABLE `sp_album_test` ( `id` int(11) NOT NULL AUTO_INCREMENT, `name` varchar(255) DEFAULT ‘‘ COMMENT ‘相册名称‘, `uid` int(11) DEFAULT ‘0‘ COMMENT ‘用户id‘, `add_time` bigint(13) DEFAULT ‘0‘ COMMENT ‘创建时间‘, `content` longtext COMMENT ‘简介‘, `pic` longblob COMMENT ‘图像‘, PRIMARY KEY (`id`) ) ENGINE=MyISAM AUTO_INCREMENT=2 DEFAULT CHARSET=utf8 COMMENT=‘相册1‘ CREATE TABLE `sp_account` ( `id` int(11) NOT NULL AUTO_INCREMENT, `accountName` varchar(255) DEFAULT ‘‘ COMMENT ‘转账用户‘, `accountBalance` double DEFAULT ‘0‘ COMMENT ‘转账金额‘, PRIMARY KEY (`id`) ) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8 COMMENT=‘银行转账--Java测试‘
时间： 2024-10-13 11:42:41