我要评论1.引入依赖
<dependency> <groupid>mysql</groupid> <artifactid>mysql-connector-java</artifactid> <version>5.1.45</version> </dependency>
2.项目目录结构
jdbc.properties内容
driver=com.mysql.jdbc.driver url=jdbc:mysql://localhost:3306/shiro?useunicode=true&characterencoding=utf-8&usessl=false username=root password=123456
util类
package com.cxb.shiro;
import java.io.ioexception;
import java.util.properties;
/**
* 获取资源文件的util
* @author 81046
*
*/
public class propertiesutil {
static properties properties = new properties();
public propertiesutil() {
}
public static boolean loadfile(string filename){
try {
properties.load(propertiesutil.class.getclassloader().getresourceasstream(filename));
} catch (ioexception e) {
e.printstacktrace();
return false;
}
return true;
}
public static string getpropertyvalue(string key){
return properties.getproperty(key);
}
}
package com.cxb.shiro;
import java.sql.connection;
import java.sql.drivermanager;
import java.sql.sqlexception;
public class jdbcutils {
//通过上面的工具就可以获取到properties文件中的键值从而可以加载驱动 获取链接 从而 可以增删改查
private static connection conn = null;
public static connection getconn(){
propertiesutil.loadfile("jdbc.properties");
string driver = propertiesutil.getpropertyvalue("driver");
string url = propertiesutil.getpropertyvalue("url");
string username = propertiesutil.getpropertyvalue("username");
string password = propertiesutil.getpropertyvalue("password");
try {
class.forname(driver);
conn = drivermanager.getconnection(url,username,password);
} catch (classnotfoundexception e) {
e.printstacktrace();
} catch (sqlexception e) {
e.printstacktrace();
close();
}
return conn;
}
public static void close(){
try {
conn.close();
} catch (sqlexception e) {
e.printstacktrace();
}
}
}
/**
* 通过用户名到数据库中获取凭证密码
* @param username
* @return
*/
private static string getpasswordbyusername(string username) {
//sql语句
string sql = "select password from users where username = " +"'" + username+"'";
connection conn = jdbcutils.getconn();
statement stmt=null;
resultset ret = null;
string password=null;
try {
stmt = conn.createstatement();
//执行语句，得到结果集
ret = stmt.executequery(sql);
while (ret.next()) {
//这里只查询的密码
password = ret.getstring(1);
}
ret.close();
conn.close();//关闭连接
} catch (sqlexception e1) {
e1.printstacktrace();
}
return password;
}总结
以上为个人经验，希望能给大家一个参考，也希望大家多多支持代码网。
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