<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-data-jdbcartifactId>
dependency>
可以看到没有帮我们导入驱动,因为SpringBoot不会知道我们使用的是什么数据库
默认版本:<mysql.version>8.0.22mysql.version>
<dependency>
<groupId>mysqlgroupId>
<artifactId>mysql-connector-javaartifactId>
dependency>
想要修改版本
1、直接依赖引入具体版本(maven的就近依赖原则)
2、重新声明版本(maven的属性的就近优先原则)
<properties>
<java.version>1.8java.version>
<mysql.version>5.1.49mysql.version>
properties>
@Configuration(proxyBeanMethods = false)
@Conditional(PooledDataSourceCondition.class)
@ConditionalOnMissingBean({ DataSource.class, XADataSource.class })
@Import({ DataSourceConfiguration.Hikari.class, DataSourceConfiguration.Tomcat.class,
DataSourceConfiguration.Dbcp2.class, DataSourceConfiguration.OracleUcp.class,
DataSourceConfiguration.Generic.class, DataSourceJmxConfiguration.class })
protected static class PooledDataSourceConfiguration
spring:
datasource:
url: jdbc:mysql://localhost:3306/db_account
username: root
password: 123456
driver-class-name: com.mysql.jdbc.Driver
@Slf4j
@SpringBootTest
class Boot05WebAdminApplicationTests {
@Autowired
JdbcTemplate jdbcTemplate;
@Test
void contextLoads() {
Long aLong = jdbcTemplate.queryForObject("select count(*) from account_tbl", Long.class);
log.info("记录总数:{}",aLong);
}
}
druid github地址
整合第三方技术的两种方式
<dependency>
<groupId>com.alibabagroupId>
<artifactId>druidartifactId>
<version>1.1.17version>
dependency>
<bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource"
destroy-method="close">
<property name="url" value="${jdbc.url}" />
<property name="username" value="${jdbc.username}" />
<property name="password" value="${jdbc.password}" />
<property name="maxActive" value="20" />
<property name="initialSize" value="1" />
<property name="maxWait" value="60000" />
<property name="minIdle" value="1" />
<property name="timeBetweenEvictionRunsMillis" value="60000" />
<property name="minEvictableIdleTimeMillis" value="300000" />
<property name="testWhileIdle" value="true" />
<property name="testOnBorrow" value="false" />
<property name="testOnReturn" value="false" />
<property name="poolPreparedStatements" value="true" />
<property name="maxOpenPreparedStatements" value="20" />
StatViewServlet 的用途
提供监控信息展示的html页面
提供监控信息的JSON API
<servlet>
<servlet-name>DruidStatViewservlet-name>
<servlet-class>com.alibaba.druid.support.http.StatViewServletservlet-class>
servlet>
<servlet-mapping>
<servlet-name>DruidStatViewservlet-name>
<url-pattern>/druid/*url-pattern>
servlet-mapping>
用于统计监控信息;如SQL监控、URI监控
需要给数据源中配置如下属性;可以允许多个filter,多个用,分割;如:
<property name="filters" value="stat,slf4j" />
<bean id="stat-filter" class="com.alibaba.druid.filter.stat.StatFilter">
<property name="slowSqlMillis" value="10000" />
<property name="logSlowSql" value="true" />
bean>
使用 slowSqlMillis 定义慢SQL的时长
<dependency>
<groupId>com.alibabagroupId>
<artifactId>druid-spring-boot-starterartifactId>
<version>1.1.17version>
dependency>
DruidSpringAopConfiguration.class
: 监控SpringBean的;配置项:spring.datasource.druid.aop-patternsDruidStatViewServletConfiguration.class
: 监控页的配置:spring.datasource.druid.stat-view-servlet;默认开启DruidWebStatFilterConfiguration.class
: web监控配置;spring.datasource.druid.web-stat-filter;默认开启DruidFilterConfiguration.class
:所有 Druid 自己 filter 的配置 private static final String FILTER_STAT_PREFIX = "spring.datasource.druid.filter.stat";
private static final String FILTER_CONFIG_PREFIX = "spring.datasource.druid.filter.config";
private static final String FILTER_ENCODING_PREFIX = "spring.datasource.druid.filter.encoding";
private static final String FILTER_SLF4J_PREFIX = "spring.datasource.druid.filter.slf4j";
private static final String FILTER_LOG4J_PREFIX = "spring.datasource.druid.filter.log4j";
private static final String FILTER_LOG4J2_PREFIX = "spring.datasource.druid.filter.log4j2";
private static final String FILTER_COMMONS_LOG_PREFIX = "spring.datasource.druid.filter.commons-log";
private static final String FILTER_WALL_PREFIX = "spring.datasource.druid.filter.wall";
spring:
datasource:
url: jdbc:mysql://localhost:3306/db_account
username: root
password: 123456
driver-class-name: com.mysql.jdbc.Driver
druid:
aop-patterns: com.atguigu.admin.* #监控SpringBean
filters: stat,wall # 底层开启功能,stat(sql监控),wall(防火墙)
stat-view-servlet: # 配置监控页功能
enabled: true
login-username: admin
login-password: admin
resetEnable: false
web-stat-filter: # 监控web
enabled: true
urlPattern: /*
exclusions: '*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*'
filter:
stat: # 对上面filters里面的stat的详细配置
slow-sql-millis: 1000
logSlowSql: true
enabled: true
wall:
enabled: true
config:
drop-table-allow: false
官方地址
Mybatis官方
官方 starter spring-boot-starter-*
第三方 *-spring-boot-starter
<dependency>
<groupId>org.mybatis.spring.bootgroupId>
<artifactId>mybatis-spring-boot-starterartifactId>
<version>2.1.4version>
dependency>
SqlSessionFactory
: 自动配置好了SqlSession
:自动配置了 SqlSessionTemplate 组合了SqlSession@Import(AutoConfiguredMapperScannerRegistrar.class)
;@EnableConfigurationProperties(MybatisProperties.class) : MyBatis配置项绑定类。
@AutoConfigureAfter({ DataSourceAutoConfiguration.class, MybatisLanguageDriverAutoConfiguration.class })
public class MybatisAutoConfiguration{}
@ConfigurationProperties(prefix = "mybatis")
public class MybatisProperties
# 配置mybatis规则
mybatis:
config-location: classpath:mybatis/mybatis-config.xml #全局配置文件位置
mapper-locations: classpath:mybatis/mapper/*.xml #sql映射文件位置
Mapper接口--->绑定Xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
>
<!-- public Account getAcct(Long id); -->
>
配置 private Configuration configuration; mybatis.configuration下面的所有,就是相当于改mybatis全局配置文件中的值
# 配置mybatis规则
mybatis:
# config-location: classpath:mybatis/mybatis-config.xml
mapper-locations: classpath:mybatis/mapper/*.xml
configuration:
map-underscore-to-camel-case: true
# 可以不写全局;配置文件,所有全局配置文件的配置都放在configuration配置项中即可
● 导入mybatis官方starter
● 编写mapper接口。标准@Mapper注解
● 编写sql映射文件并绑定mapper接口
● 在application.yaml中指定Mapper配置文件的位置,以及指定全局配置文件的信息 (建议;配置在mybatis.configuration)
@Mapper
public interface CityMapper {
@Select("select * from city where id=#{id}")
public City getById(Long id);
public void insert(City city);
}
@Mapper
public interface CityMapper {
@Select("select * from city where id=#{id}")
public City getById(Long id);
public void insert(City city);
}
● 引入mybatis-starter
● 配置application.yaml中,指定mapper-location位置即可
● 编写Mapper接口并标注@Mapper注解
● 简单方法直接注解方式
● 复杂方法编写mapper.xml进行绑定映射
● @MapperScan(“com.atguigu.admin.mapper”) 简化,其他的接口就可以不用标注@Mapper注解
MyBatis-Plus(简称 MP)是一个 MyBatis 的增强工具,在 MyBatis 的基础上只做增强不做改变,为简化开发、提高效率而生。
mybatis plus 官网
建议安装 MybatisX 插件
<dependency>
<groupId>com.baomidougroupId>
<artifactId>mybatis-plus-boot-starterartifactId>
<version>3.4.1version>
dependency>
自动配置
● MybatisPlusAutoConfiguration 配置类,MybatisPlusProperties 配置项绑定。mybatis-plus:xxx 就是对mybatis-plus的定制
● SqlSessionFactory 自动配置好。底层是容器中默认的数据源
● mapperLocations 自动配置好的。有默认值。classpath*:/mapper/**/*.xml;任意包的类路径下的所有mapper文件夹下任意路径下的所有xml都是sql映射文件。 建议以后sql映射文件,放在 mapper下
● 容器中也自动配置好了 SqlSessionTemplate
● @Mapper 标注的接口也会被自动扫描;建议直接 @MapperScan(“com.atguigu.admin.mapper”) 批量扫描就行
优点:
● 只需要我们的Mapper继承 BaseMapper 就可以拥有crud能力
@GetMapping("/user/delete/{id}")
public String deleteUser(@PathVariable("id") Long id,
@RequestParam(value = "pn",defaultValue = "1")Integer pn,
RedirectAttributes ra){
userService.removeById(id);
ra.addAttribute("pn",pn);
return "redirect:/dynamic_table";
}
@GetMapping("/dynamic_table")
public String dynamic_table(@RequestParam(value="pn",defaultValue = "1") Integer pn,Model model){
//表格内容的遍历
//从数据库中查出user表中的用户进行展示
//构造分页参数
Page<User> page = new Page<>(pn, 2);
//调用page进行分页
Page<User> userPage = userService.page(page, null);
model.addAttribute("users",userPage);
return "table/dynamic_table";
}
@Service
public class UserServiceImpl extends ServiceImpl<UserMapper,User> implements UserService {
}
public interface UserService extends IService<User> {
}
Redis 是一个开源(BSD许可)的,内存中的数据结构存储系统,它可以用作数据库、缓存和消息中间件。 它支持多种类型的数据结构,如 字符串(strings), 散列(hashes), 列表(lists), 集合(sets), 有序集合(sorted sets) 与范围查询, bitmaps, hyperloglogs 和 地理空间(geospatial) 索引半径查询。 Redis 内置了 复制(replication),LUA脚本(Lua scripting), LRU驱动事件(LRU eviction),事务(transactions) 和不同级别的 磁盘持久化(persistence), 并通过 Redis哨兵(Sentinel)和自动 分区(Cluster)提供高可用性(high availability)。
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-data-redisartifactId>
dependency>
自动配置:
阿里云环境搭建
1、阿里云按量付费redis。经典网络
2、申请redis的公网连接地址
3、修改白名单 允许0.0.0.0/0 访问
@Test
void testRedis(){
ValueOperations<String, String> operations = redisTemplate.opsForValue();
operations.set("hello","world");
String hello = operations.get("hello");
System.out.println(hello);
}
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-data-redisartifactId>
dependency>
<dependency>
<groupId>redis.clientsgroupId>
<artifactId>jedisartifactId>
dependency>
spring:
redis:
host: r-bp1nc7reqesxisgxpipd.redis.rds.aliyuncs.com
port: 6379
password: lfy:Lfy123456
client-type: jedis
jedis:
pool:
max-active: 10