Statement缺点-马育民老师

废弃，详见：[SQL注入与Statement缺点](https://www.malaoshi.top/show_1IX2aMXBCjLn.html "SQL注入与Statement缺点")

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在登录时会发生sql注入

```
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

public class SQL注入 {

public static void main(String[] args) throws Exception {
		// TODO Auto-generated method stub
		String url = "jdbc:mysql://127.0.0.1:3308/scott?useSSL=false";
		
//		正常的用户名、密码
//		String username = "lilei";
//		String password = "123456";

// sql注入
		String username = "' or 1=1 #";
		String password = "";

// 加载驱动
		Class.forName("com.mysql.jdbc.Driver");

Connection conn = DriverManager.getConnection(url, "root", "");
		
		Statement stmt = conn.createStatement();

String sql = "SELECT * FROM USER WHERE username='" + username + "' and password='"+ password + "'";
		System.out.println(sql);
		
		ResultSet rs = stmt.executeQuery(sql);

if (rs.next()) {
			String id = rs.getString(1);
			Object name = rs.getObject(2);
			Object passowrd = rs.getObject(3);

System.out.println("登录成功！");
			System.out.println(id + "," + name + "," + passowrd);
		} else {// 没有查询到此用户、密码，说明登录失败
			System.out.println("输入用户名或密码错误，请重新输入！");
		}

conn.close();
	}

}
```

原文出处：http://malaoshi.top/show_1EF63mLv7JCM.html