Java與Mysql基礎(chǔ)應(yīng)用
確保已有java jdk
確保已安裝mysql
1.百度搜索 mysql-connector-java-8.0.21.jar 并下載
2.在項(xiàng)目中創(chuàng)建lib文件夾并放入 mysql-connector-java-8.0.21.jar
3.右鍵 mysql-connector-java-8.0.21.jar =>Build Path=>Add to Build Path
Java獲取Mysql數(shù)據(jù)
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class MainTest {
public static void main(String[] args) {
// 聲明Connection對(duì)象
Connection con;
// 驅(qū)動(dòng)程序名
String driver = "com.mysql.cj.jdbc.Driver";
// URL指向要訪問的數(shù)據(jù)庫名 test
String url = "jdbc:mysql://localhost:3306/test?serverTimezone=UTC&useSSL=false";
// MySQL配置時(shí)的用戶名
String user = "root";
// MySQL配置時(shí)的密碼
String password = "********";
// 遍歷查詢結(jié)果集
try {
// 加載驅(qū)動(dòng)程序
Class.forName(driver);//此驅(qū)動(dòng)程序在4.0版本后可不在加載 不加載也可正常使用
//靜態(tài)代碼塊--->類加載，就執(zhí)行 為防二次注冊(cè) 推薦使用Class.forName加載驅(qū)動(dòng)
//DriverManager.registerDriver(new com.mysql.cj.jdbc.Driver());
// 1.getConnection()方法，連接MySQL數(shù)據(jù)庫?。?/span>
con = DriverManager.getConnection(url, user, password);
if (!con.isClosed())//判斷是否成功連接
System.out.println("ntt成功以 " + user + " 身份連接到數(shù)據(jù)庫?。?！");
// 2.創(chuàng)建statement類對(duì)象，用來執(zhí)行SQL語句?。?/span>
Statement st = con.createStatement();
// 要執(zhí)行的SQL語句
String sql = "select * from author";
// 3.ResultSet類，用來存放獲取的結(jié)果集??！
ResultSet rs = st.executeQuery(sql);
int ID = 0;
String Name = null;
String Sex = null;
int Age = 0;
System.out.println("ntt執(zhí)行結(jié)果如下所示:");
System.out.println("tt-----------------------------------------------------------------");
System.out.println("tt|t" + "ID" + "t" + "姓名" + "tt" + "性別" + "t" + "年齡t|");
System.out.println("tt-----------------------------------------------------------------");
while (rs.next()) {//4.遍歷查詢
// 獲取 ID 這列數(shù)據(jù)
ID = rs.getInt("id");
// 獲取 Name 這列數(shù)據(jù)
Name = rs.getString("author");
// 獲取 Sex 這列數(shù)據(jù)
Sex = rs.getString("sex");
// 獲取 Age 這列數(shù)據(jù)
Age = rs.getInt("age");
// 輸出結(jié)果
System.out.println("tt|t" + ID + "t" + Name + "tt" + Sex + "t" + Age + "t|tt");
}
System.out.println("tt-----------------------------------------------------------------");
rs.close();//5.釋放資源
st.close();
con.close();
}
catch (ClassNotFoundException e) {
// 數(shù)據(jù)庫驅(qū)動(dòng)類異常處理
System.out.println("Sorry,can`t find the Driver!");
e.printStackTrace();
}
catch (SQLException e) {
// 數(shù)據(jù)庫連接失敗異常處理
e.printStackTrace();
}
catch (Exception e) {
e.printStackTrace();
}
finally {
System.out.println("tttttttt獲取數(shù)據(jù)庫數(shù)據(jù)完畢！?。?);
}
}
}
運(yùn)行結(jié)果：
成功以 root 身份連接到數(shù)據(jù)庫?。?！
執(zhí)行結(jié)果如下所示:
-----------------------------------------------------------------
| ID 姓名 性別 年齡 |
-----------------------------------------------------------------
| 1 yj man 22 |
| 2 迪麗熱巴 girl 18 |
| 3 阿巴阿巴 pig 1 |
-----------------------------------------------------------------
獲取數(shù)據(jù)庫數(shù)據(jù)完畢?。?！優(yōu)化釋放資源 close
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class JDBCUti {
public static void main(String[] args) {
// 聲明Connection對(duì)象
Connection con = null;
// 驅(qū)動(dòng)程序名
String driver = "com.mysql.cj.jdbc.Driver";
// URL指向要訪問的數(shù)據(jù)庫名 test
String url = "jdbc:mysql://localhost:3306/test?serverTimezone=UTC&useSSL=false";
// MySQL配置時(shí)的用戶名
String user = "root";
// MySQL配置時(shí)的密碼
String password = "********";
// 聲明Statement對(duì)象 用來執(zhí)行SQL語句
Statement st = null;
// 聲明ResultSet對(duì)象 ResultSet類，用來存放獲取的結(jié)果集?。?/span>
ResultSet rs = null;
// 遍歷查詢結(jié)果集
try {
// 加載驅(qū)動(dòng)程序
Class.forName(driver);
// 1.getConnection()方法，連接MySQL數(shù)據(jù)庫??！
con = DriverManager.getConnection(url, user, password);
if (!con.isClosed())//判斷是否成功連接
System.out.println("ntt成功以 " + user + " 身份連接到數(shù)據(jù)庫?。。?);
// 2.創(chuàng)建statement類對(duì)象，用來執(zhí)行SQL語句??！
st = con.createStatement();
// 要執(zhí)行的SQL語句
String sql = "select * from author";
// 3.ResultSet類，用來存放獲取的結(jié)果集??！
rs = st.executeQuery(sql);
int ID = 0;
String Name = null;
String Sex = null;
int Age = 0;
System.out.println("ntt執(zhí)行結(jié)果如下所示:");
System.out.println("tt-----------------------------------------------------------------");
System.out.println("tt|t" + "ID" + "t" + "姓名" + "tt" + "性別" + "t" + "年齡t|");
System.out.println("tt-----------------------------------------------------------------");
while (rs.next()) {//4.遍歷查詢
// 獲取 ID 這列數(shù)據(jù)
ID = rs.getInt("id");
// 獲取 Name 這列數(shù)據(jù)
Name = rs.getString("author");
// 獲取 Sex 這列數(shù)據(jù)
Sex = rs.getString("sex");
// 獲取 Age 這列數(shù)據(jù)
Age = rs.getInt("age");
// 輸出結(jié)果
System.out.println("tt|t" + ID + "t" + Name + "tt" + Sex + "t" + Age + "t|tt");
}
System.out.println("tt-----------------------------------------------------------------");
}
catch (ClassNotFoundException e) {
// 數(shù)據(jù)庫驅(qū)動(dòng)類異常處理
System.out.println("Sorry,can`t find the Driver!");
e.printStackTrace();
}
catch (SQLException e) {
// 數(shù)據(jù)庫連接失敗異常處理
e.printStackTrace();
}
catch (Exception e) {
e.printStackTrace();
}
finally {
//5.優(yōu)化釋放資源
JDBCUtil.release(con, st, rs);
System.out.println("tttttttt獲取數(shù)據(jù)庫數(shù)據(jù)完畢！??！");
}
}
}import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
/*
* 關(guān)閉的封裝
*/
public class JDBCUtil {
public static void release(Connection con,Statement st,ResultSet rs) {
closeRs(rs);
closeSt(st);
closeConn(con);
}
private static void closeRs(ResultSet rs) {
try {
if(rs != null) {
rs.close();
}
}
catch(SQLException e) {
e.printStackTrace();
}
finally {
rs = null;
}
}
private static void closeSt(Statement st) {
try {
if(st != null) {
st.close();
}
}
catch(SQLException e) {
e.printStackTrace();
}
finally {
st = null;
}
}
private static void closeConn(Connection con) {
try {
if(con != null) {
con.close();
}
}
catch(SQLException e) {
e.printStackTrace();
}
finally {
con = null;
}
}
}優(yōu)化連接對(duì)象
import java.io.ObjectInputStream.GetField;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
class JDBC{
public static Connection getCon() {//獲取連接對(duì)象
// 聲明Connection對(duì)象
Connection con = null;
// 驅(qū)動(dòng)程序名
String driver = "com.mysql.cj.jdbc.Driver";
// URL指向要訪問的數(shù)據(jù)庫名 test
String url = "jdbc:mysql://localhost:3306/test?serverTimezone=UTC&useSSL=false";
// MySQL配置時(shí)的用戶名
String user = "root";
// MySQL配置時(shí)的密碼
String password = "********";
try {
// 加載驅(qū)動(dòng)程序
Class.forName(driver);
// 1.getConnection()方法，連接MySQL數(shù)據(jù)庫?。?/span>
con = DriverManager.getConnection(url, user, password);
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return con;
}
}
public class Demo1 {
public static void main(String[] args) {
// 聲明Connection對(duì)象
Connection con = null;
// 聲明Statement對(duì)象 用來執(zhí)行SQL語句
Statement st = null;
// 聲明ResultSet對(duì)象 ResultSet類，用來存放獲取的結(jié)果集?。?/span>
ResultSet rs = null;
// 遍歷查詢結(jié)果集
try {
con = JDBC.getCon();
if (!con.isClosed())//判斷是否成功連接
System.out.println("ntt成功連接到數(shù)據(jù)庫?。。?);
// 2.創(chuàng)建statement類對(duì)象，用來執(zhí)行SQL語句！！
st = con.createStatement();
// 要執(zhí)行的SQL語句
String sql = "select * from author";
// 3.ResultSet類，用來存放獲取的結(jié)果集??！
rs = st.executeQuery(sql);
int ID = 0;
String Name = null;
String Sex = null;
int Age = 0;
System.out.println("ntt執(zhí)行結(jié)果如下所示:");
System.out.println("tt-----------------------------------------------------------------");
System.out.println("tt|t" + "ID" + "t" + "姓名" + "tt" + "性別" + "t" + "年齡t|");
System.out.println("tt-----------------------------------------------------------------");
while (rs.next()) {//4.遍歷查詢
// 獲取 ID 這列數(shù)據(jù)
ID = rs.getInt("id");
// 獲取 Name 這列數(shù)據(jù)
Name = rs.getString("author");
// 獲取 Sex 這列數(shù)據(jù)
Sex = rs.getString("sex");
// 獲取 Age 這列數(shù)據(jù)
Age = rs.getInt("age");
// 輸出結(jié)果
System.out.println("tt|t" + ID + "t" + Name + "tt" + Sex + "t" + Age + "t|tt");
}
System.out.println("tt-----------------------------------------------------------------");
}
catch (SQLException e) {
// 數(shù)據(jù)庫連接失敗異常處理
e.printStackTrace();
}
catch (Exception e) {
e.printStackTrace();
}
finally {
//5.釋放資源
JDBCUtil.release(con, st, rs);
System.out.println("tttttttt獲取數(shù)據(jù)庫數(shù)據(jù)完畢！??！");
}
}
}配置文件 properties
1.在src下聲明jdbc.properties文件
driverClass=com.mysql.cj.jdbc.Driver
url=jdbc:mysql://localhost:3306/test?serverTimezone=UTC&useSSL=false
user=root
password=xxxxxxxx2.在工具類中使用靜態(tài)代碼塊讀取屬性
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream.GetField;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;
import com.test.JDBCUtil;
/*
*使用配置文件
*/
class JDBC{
// 聲明Connection對(duì)象
static Connection con = null;
// 驅(qū)動(dòng)程序名
static String driver = null;
// URL指向要訪問的數(shù)據(jù)庫名 test
static String url = null;
// MySQL配置時(shí)的用戶名
static String user = null;
// MySQL配置時(shí)的密碼
static String password = null;
static {
try {
//創(chuàng)建一個(gè)屬性配置對(duì)象
Properties properties = new Properties();
//InputStream is = new FileInputStream("jdbc.properties");//放項(xiàng)目根目錄下則可使用 如放在src下則報(bào)錯(cuò)未找到
//使用類加載器，讀取src底下的資源文件
InputStream is = JDBCUtil.class.getClassLoader().getResourceAsStream("jdbc.properties");
//導(dǎo)入輸入流
properties.load(is);
//讀取屬性
driver = properties.getProperty("driverClass");
url = properties.getProperty("url");
user = properties.getProperty("user");
password = properties.getProperty("password");
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static Connection getCon() {//獲取連接對(duì)象
try {
// 加載驅(qū)動(dòng)程序
Class.forName(driver);
// 1.getConnection()方法，連接MySQL數(shù)據(jù)庫?。?/span>
con = DriverManager.getConnection(url, user, password);
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return con;
}
}
public class Demo2 {
public static void main(String[] args) {
// 聲明Connection對(duì)象
Connection con = null;
// 聲明Statement對(duì)象 用來執(zhí)行SQL語句
Statement st = null;
// 聲明ResultSet對(duì)象 ResultSet類，用來存放獲取的結(jié)果集！！
ResultSet rs = null;
// 遍歷查詢結(jié)果集
try {
con = JDBC.getCon();
if (!con.isClosed())//判斷是否成功連接
System.out.println("ntt成功連接到數(shù)據(jù)庫?。?！");
// 2.創(chuàng)建statement類對(duì)象，用來執(zhí)行SQL語句??！
st = con.createStatement();
// 要執(zhí)行的SQL語句
String sql = "select * from author";
// 3.ResultSet類，用來存放獲取的結(jié)果集??！
rs = st.executeQuery(sql);
int ID = 0;
String Name = null;
String Sex = null;
int Age = 0;
System.out.println("ntt執(zhí)行結(jié)果如下所示:");
System.out.println("tt-----------------------------------------------------------------");
System.out.println("tt|t" + "ID" + "t" + "姓名" + "tt" + "性別" + "t" + "年齡t|");
System.out.println("tt-----------------------------------------------------------------");
while (rs.next()) {//4.遍歷查詢
// 獲取 ID 這列數(shù)據(jù)
ID = rs.getInt("id");
// 獲取 Name 這列數(shù)據(jù)
Name = rs.getString("author");
// 獲取 Sex 這列數(shù)據(jù)
Sex = rs.getString("sex");
// 獲取 Age 這列數(shù)據(jù)
Age = rs.getInt("age");
// 輸出結(jié)果
System.out.println("tt|t" + ID + "t" + Name + "tt" + Sex + "t" + Age + "t|tt");
}
System.out.println("tt-----------------------------------------------------------------");
}
catch (SQLException e) {
// 數(shù)據(jù)庫連接失敗異常處理
e.printStackTrace();
}
catch (Exception e) {
e.printStackTrace();
}
finally {
//5.釋放資源
JDBCUtil.release(con, st, rs);
System.out.println("tttttttt獲取數(shù)據(jù)庫數(shù)據(jù)完畢！??！");
}
}
}Mysql的CRUD
常見的MySQL語句命令
進(jìn)入mysql 命令行：mysql -uroot -p;
查看所有數(shù)據(jù)庫：show databases;
創(chuàng)建數(shù)據(jù)庫：create database niu charset utf8;
刪除數(shù)據(jù)庫：drop database niu;
選擇數(shù)據(jù)庫：use databases;
查看所有表：show tables;
查看創(chuàng)建數(shù)據(jù)庫的語句：show create database databasename;
查看創(chuàng)建表的語句：show create table tablename;
查看表結(jié)構(gòu)：desc tablenmae;
庫操作
創(chuàng)建數(shù)據(jù)庫：create database shujukuba;
創(chuàng)建帶字符集的數(shù)據(jù)庫：create database mydb2 CHARACTER SET=utf8;
創(chuàng)建帶校驗(yàn)的數(shù)據(jù)庫：create database mydb3 CHARACTER SET=utf8 COLLATE utf8_general_ci;
顯示數(shù)據(jù)庫：show databases;
刪除數(shù)據(jù)庫：drop database shujukuba;
修改數(shù)據(jù)庫編碼：ALTER DATABASE shujukuba character set gb2312;
表操作
創(chuàng)建數(shù)據(jù)庫表（創(chuàng)建一個(gè)表名為：employee，該表中含有id、name、sex、birthday、job字段）：
create table employee
(
id int,
name varchar(40),
sex char(4),
birthday date,
job varchar(100),
);
表中增加image字段：alter table employee add image blob;
修改job值，使其長度為60（原長度為1000）：alter table employee modify job varchar(60);
刪除sex列：alter table employee drop sex;
表名改為user（原名employee）：rename table employee to user;
修改表的字符集為utf-8：alter table user character set utf8;
列name修改為username：alter table user change column name username varchar(100);
刪除表：drop table user;
增刪改查實(shí)例
新建表employee：
create table employee
(
id int,
name varchar(40),
sex varchar(4),
birthday date,
entry_date date,
salary decimal(8,2),
resume text
);
插入數(shù)據(jù)：
insert into employee(id,name,sex,birthday,entry_date,salary,resume) values(1,'zhangsan','male','1993-03-04','2016-11-10','1000','i am a developer');
指定某些列插入數(shù)據(jù)：insert into employee(id) values(6);
插入漢字：insert into employee(id,name) values(6,'張三');
修改表數(shù)據(jù)：
將所有員工薪水修改為5000元：update employee set salary=5000;
將姓名為’zs’的員工薪水修改為3000元：update employee set salary = 3000 where name='zhangsan';
將姓名為’aaa’的員工薪水修改為4000元,job改為ccc：update employee set salary = 4000,job='ccc' where name='張三';
將wu的薪水在原有基礎(chǔ)上增加1000元：update employee set salary = salary+1000 where name='張三';
刪除表數(shù)據(jù)：
刪除表中名稱為“zs”的記錄：delete from employee where job='ccc';
刪除表中所有記錄：delete from employee;
使用truncate刪除表中記錄：truncate table employee;
查詢表數(shù)據(jù)：
查詢表中所有學(xué)生的信息：select id,name,chinese,english,math from student;
查詢表中所有學(xué)生的姓名和對(duì)應(yīng)的英語成績(jī)：select name,english from student;
查詢姓名為wu的學(xué)生成績(jī)：select * from student where name='張三';
查詢英語成績(jī)大于90分的同學(xué)：select * from student where english>'90';
查詢英語分?jǐn)?shù)在 80－90之間的同學(xué)：select * from student where english>=80 and english=<90;
常見MySQL字段含義
自增長：auto_increment
非空：not null
默認(rèn)值：default
唯一：unique
指定字符集：charset
主鍵：primary key使用單元測(cè)試，測(cè)試代碼
1.定義一個(gè)類，TestXXXX，里面定義方法testXXX
2.添加junit的支持
右鍵工程 --- Build Path --- add Library --- Junit --- Junit43.在方法的上面加上注釋（標(biāo)記）
@Test
public void testQuery(){
...
}4.光標(biāo)選中方法名字，然后右鍵執(zhí)行單元測(cè)試。或打開outline視圖，然后選擇方法右鍵執(zhí)行
插入
//核心代碼
// 要執(zhí)行的SQL語句
String sql = "insert into user(name,sex,birthday,entry_date,salary,resume) values('xx','man','199x-xx-xx','2020-7-11','1000','i am a developer')";
// ResultSet類，存放獲取的結(jié)果集
rs = st.executeQuery(sql);
if(rs>0){
System.out.println("添加成功");
}else{
System.out.println("添加失敗");
}刪除
//核心代碼
// 要執(zhí)行的SQL語句
String sql = "delete from user where id=2";
// ResultSet類，存放獲取的結(jié)果集
rs = st.executeQuery(sql);
if(rs>0){
System.out.println("刪除成功");
}else{
System.out.println("刪除失敗");
}更新
//核心代碼
// 要執(zhí)行的SQL語句
String sql = "update user set name='yj',birthday='1998-xx-xx' where id=1";
// ResultSet類，存放獲取的結(jié)果集
rs = st.executeQuery(sql);
if(rs>0){
System.out.println("刪除成功");
}else{
System.out.println("刪除失敗");
}//核心代碼
// 要執(zhí)行的SQL語句
String sql = "update user set name=?,birthday=? where id=?";
PreparedStatement ps = con.prepareStatement(sql);
ps.setString(1,"姓名");//從左到右數(shù) 1代表第一個(gè)?
ps.setString(2,"生日");//傳入什么類型 就set什么類型
ps.setInt(3,1);
rs = ps.executeQuery();
if(rs>0){
System.out.println("刪除成功");
}else{
System.out.println("刪除失敗");
}//封裝成通用方法
public static int executeDML(String sql,Object...objs){//sql為要執(zhí)行的mysql語句
try {
ps = con.prepareStatement(sql);
for(int i=0;i<objs.length;i++){
ps.setObject(i+1,objs[i]);
}
return ps.executeUpdate();
} catch (SQLException e) {
e.printStackTrace();
}
return -1;
}完結(jié)封裝
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream.GetField;
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 java.util.Properties;
import com.test.JDBCUtil;
class JDBC{
// 聲明Connection對(duì)象
static Connection con = null;
// 驅(qū)動(dòng)程序名
static String driver = null;
// URL指向要訪問的數(shù)據(jù)庫名 test
static String url = null;
// MySQL配置時(shí)的用戶名
static String user = null;
// MySQL配置時(shí)的密碼
static String password = null;
static {
try {
//創(chuàng)建一個(gè)屬性配置對(duì)象
Properties properties = new Properties();
//InputStream is = new FileInputStream("jdbc.properties");//放項(xiàng)目根目錄下則可使用 如放在src下則報(bào)錯(cuò)未找到
//使用類加載器，讀取src底下的資源文件
InputStream is = JDBCUtil.class.getClassLoader().getResourceAsStream("jdbc.properties");
//導(dǎo)入輸入流
properties.load(is);
//讀取屬性
driver = properties.getProperty("driverClass");
url = properties.getProperty("url");
user = properties.getProperty("user");
password = properties.getProperty("password");
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static Connection getCon() {//獲取連接對(duì)象
try {
// 加載驅(qū)動(dòng)程序
Class.forName(driver);//可省略
// 1.getConnection()方法，連接MySQL數(shù)據(jù)庫！！
con = DriverManager.getConnection(url, user, password);
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return con;
}
}
public class Demo3 {
// 聲明Connection對(duì)象
static Connection con = null;
// 聲明Statement對(duì)象 用來執(zhí)行SQL語句
static Statement st = null;
// 聲明ResultSet對(duì)象 ResultSet類，用來存放獲取的結(jié)果集！！
static ResultSet rs = null;
//聲明PreparedStatement對(duì)象，用來針對(duì)?
static PreparedStatement ps = null;
public static int executeDML(String sql,Object...objs){//sql為要執(zhí)行的mysql語句
//增刪改的封裝方法
try {
ps = con.prepareStatement(sql);
for(int i=0;i<objs.length;i++){
ps.setObject(i+1,objs[i]);
}
return ps.executeUpdate();
} catch (SQLException e) {
e.printStackTrace();
}
return -1;
}
public static void main(String[] args) {
try {
con = JDBC.getCon();
st = con.createStatement();
// 要執(zhí)行的SQL語句
String sql = "update user set name=?,birthday=? where id=?";
int i = executeDML(sql, "蒼老師","2100-10-10",1);//此封裝方法可以將增 刪 改 合為一句
if(i>0){
System.out.println("修改成功");
}else{
System.out.println("修改失敗");
}
}
catch (SQLException e) {
// 數(shù)據(jù)庫連接失敗異常處理
e.printStackTrace();
}
catch (Exception e) {
e.printStackTrace();
}
finally {
//5.釋放資源
JDBCUtil.release(con, st, rs);
}
}
}
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其它服務(wù)：網(wǎng)站建設(shè)、企業(yè)郵箱、數(shù)字證書ssl、400電話、
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