--编辑my.ini配置文件内容（Mysql 8.0以上不需要，直接安装即可）
[mysql]
# 设置mysql客户端默认字符集
default-character-set=utf8
[mysqld]
#设置3306端口
port = 3306
# 设置mysql的安装目录
basedir=E:\MySQL5.7.13\mysql-5.7.13-winx64
# 设置mysql数据库的数据的存放目录
datadir=E:\MySQL5.7.13\mysql-5.7.13-winx64\data
# 允许最大连接数
max_connections=200
# 服务端使用的字符集默认为8比特编码的latin1字符集
character-set-server=utf8
# 创建新表时将使用的默认存储引擎
default-storage-engine=INNODB
# 安装好后, 免密码进入mysql
skip-grant-tables
--用管理员身份运行cmd，输入命令
//安装mysql
mysqld -install
//安装成功后,初始化数据文件
mysqld --initialize-insecure --user=mysql
//进入mysql管理界面
mysql -u root-p
//修改密码
update mysql.user set password=password('新密码') where user='root';
//mysql8修改密码
alter user 'root'@'localhost' identified by '密码'
点击连接进行下载：(mysql驱动)
https://github.com/epochong/mysql-connector-java-8.0.16.git
下载后在idea目录下新建lib目录，将下载好的驱动移动到lib目录下，并右击点击添加为库，再次点击驱动文件，若能展开，则驱动安装成功。
连接过程若出现驱动问题，需要注意查看驱动是否添加为库，英文版（add as library），查看驱动版本的问题（下载驱动需要对应与数据库，例mysql下载mysql驱动，sql server下载的是sql server驱动，查看是否在同一包下，有时候不在同一包下会找不到驱动）。
package jdbc_excise;
import java.sql.*;
public class Jdbc {
public static void main(String[] args) throws SQLException {
try {
Class.forName("com.mysql.jdbc.Driver");
String url = "jdbc:mysql://localhost:3306/student?useUnicode=true&characterEncoding=utf8&useSSL=false";
//通用模板：jdbc：数据库名字：//地址：端口/实际使用数据库名称?附加参数
String username = "root";
String password = "123456";
Connection connection = DriverManager.getConnection(url,username,password);
Statement statement = connection.createStatement();
//执行sql查询语句
String sql = "select * from student";
ResultSet resultSet = statement.executeQuery(sql);
while (resultSet.next()){
System.out.println("Sno="+resultSet.getObject("Sno"));
}
resultSet.close();
statement.close();
connection.close();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
}
}
**附狂神教程中安全连接解决办法 **
jdbc:mysql://localhost:3306/student?useUnicode=true&characterEncoding=utf8&useSSL=false
若mysql版本高于驱动版本，则需要将安全连接置为false；置为true会报错。
编写配置文件
--新建配置文件：db.properties-- driver=com.mysql.jdbc.Driver url=jdbc:mysql://localhost:3306/student?useUnicode=true&characterEncoding=utf8&useSSL=false username=root password=123456
封装工具类
package connect_jdbc.utils;
import java.io.IOException;
import java.io.InputStream;
import java.sql.*;
import java.util.Properties;
public class JdbcUtils {
private static String driver = null;;
private static String url =null;
private static String username = null;
private static String password = null;
static {
try{
//通过反射得到配置文件中的内容
InputStream in = JdbcUtils.class.getClassLoader().getResourceAsStream("db.properties");
Properties properties=new Properties();
properties.load(in);
driver = properties.getProperty("driver");
url = properties.getProperty("url");
username = properties.getProperty("username");
password = properties.getProperty("password");
//加载一次驱动
Class.forName(driver);
} catch (IOException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
}
//获取连接
public static Connection getConnection() throws SQLException {
return DriverManager.getConnection(url,username,password);
}
//释放连接
public static void release(Connection conn, Statement st, ResultSet rs){
if(rs!=null){
try {
rs.close();
} catch (SQLException throwables) {
throwables.printStackTrace();
}
}
if(st!=null){
try {
st.close();
} catch (SQLException throwables) {
throwables.printStackTrace();
}
}
if(conn!=null){
try {
conn.close();
} catch (SQLException throwables) {
throwables.printStackTrace();
}
}
}
}
编写测试类执行sql语句
//执行executeUpdate语句，实现增删改
package connect_jdbc.utils;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class JdbcTest {
public static void main(String[] args) throws SQLException {
Connection connection =null;
Statement st = null;
ResultSet rs =null;
try {
connection = JdbcUtils.getConnection();
} catch (SQLException throwables) {
throwables.printStackTrace();
}
st = connection.createStatement();
String sql = "insert into student (sno, sname, ssex, sclass, stel, sgroup, spassword)" +
"values (1907040136,'贺子奇','男','1900144','15735116626',3,'123456')";
int i = st.executeUpdate(sql);//返回值为整型，表示有几行受影响
if(i>0){
System.out.println("插入成功！");
}
JdbcUtils.release(connection,st,rs);
}
}
执行select语句
//执行executeQuery语句，实现查找
package connect_jdbc.utils;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class JdbcSelect {
public static void main(String[] args) {
Connection connection = null;
Statement st = null;
ResultSet res = null;
try {
connection = JdbcUtils.getConnection();
st = connection.createStatement();
String sqls = "select * from student";
res = st.executeQuery(sqls);//返回值为查找的结果集
while (res.next())//进行结果集的输出
{
System.out.println(res.getObject("sno")+" "+res.getObject("sname"));
}
} catch (SQLException throwables) {
throwables.printStackTrace();
}
JdbcUtils.release(connection,st,res);
}
}
问题描述：在使用statement函数执行sql操作时，当输入sql语句为：’ ‘or’1=1’或者’ 'or’values>0’时则会发生恒等于从而绕过查询语句，会发生将结果集绕过密码查询出来，从而形成安全威胁。
解决办法
将原先的statement函数改用preparedStatement函数，避免了sql注入，查询效率更高。
示例：
package connect_jdbc.utils;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
public class JdbcTestSe {
public static void main(String[] args) {
Connection connection =null;
PreparedStatement statement = null;
ResultSet res = null;
try {
connection = JdbcUtils.getConnection();
//与statement的区别，要使用？占位符代替参数，进行一次预编译
String sql = "insert into student (sno, sname, ssex, sclass, stel, sgroup, spassword)" +
"values (?,?,?,?,?,?,?)";
//手动给每一个参数（？）赋值
statement=connection.prepareStatement(sql);
statement.setString(1,"1907040124");
statement.setString(2,"薛晓军");
statement.setString(3,"男");
statement.setString(4,"19070144");
statement.setString(5,"15735116626");
statement.setString(6,"3");
statement.setString(7,"123456");
//执行
int i = statement.executeUpdate();
if(i>0)
{
System.out.println("插入成功！");
}
} catch (SQLException throwables) {
throwables.printStackTrace();
}
JdbcUtils.release(connection,statement,res);
}
}
