SpringBoot--05.SpringBoot2.0學習小結
阿新 • • 發佈：2018-12-03
1、SpringBoot2.0學習小結
用springBoot建立專案時、只關注三點：《啟動器》、《全域性屬性》、《啟動類》
（1）、啟動器 ： pom.xml配置依賴
父工程座標
<parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.0.4.RELEASE</version> </parent>
新增web啟動器
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
</dependencies>管理jdk版本
<properties> <java.version>1.8</java.version> </properties>
完整pom.xml
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.leyou.demo</groupId> <artifactId>springboot-demo</artifactId> <version>1.0-SNAPSHOT</version> <properties> <java.version>1.8</java.version> </properties> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.0.4.RELEASE</version> </parent> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> </dependencies> </project>
（2）、全域性屬性：application.properties /application.yml
mybatis:
type-aliases-package: com.day01sboot.pojo
mapper-locations: classpath:mappers/**/*.xml
configuration:
map-underscore-to-camel-case: true
spring:
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://localhost:3306/mybatis?useSSL=false
username: root
password: sswqzx
server:
port: 8080
（3）、啟動類Application.java
@SpringBootApplication
@MapperScan("com.springcloud.mapper")//掃mapper包、不寫就要在mapper介面上寫
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class,args);
}
}
2、SpringBoot2.0整合SpringMvc
（1）、要在springboot中使用springmvc，只需要引入spring-boot-starter-web即可
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>（2）、自定義配置springMVC就修改application.yml
# 對映埠
server:
port: 803、SpringBoot2.0整合Jdbc和事務
(1)、在pom.xml新增SpringBoot提供的jdbc啟動器
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>（2）、資料庫驅動
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>（3）、事務：哪裡要處理事務就在哪裡添加註解、@Transactional
@Transactional
public void deleteById(Long id){
this.userMapper.deleteByPrimaryKey(id);
}（4）、連線池引數、application.yml
spring:
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://localhost:3306/mybatis
username: root
password: root4、SpringBoot2.0整合連線池
（1）、如果在pom.xml沒有引入連線池啟動器、SpringBoot自動幫我們引入了一個連線池 ：HikariCP 、名日：光
所以、只要在application.yml指定連線池引數就行了
spring:
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://localhost:3306/mybatis
username: root
password: root（2）、如果要要用其他的連線池、就在pom.xml引入依賴（啟動器）
<!-- Druid連線池 -->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
<version>1.1.6</version>
</dependency>5、SpringBoot2.0整合mybatis
(1)啟動器:也就是pom.xml依賴
<!--mybatis -->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.3.2</version>
</dependency>（2）、全域性屬性：配置resources/application.yml
mybatis:
# mybatis 別名掃描
type-aliases-package: com.leyou.pojo
# mapper.xml檔案位置,如果沒有對映檔案，請註釋掉
mapper-locations: classpath:mappers/**/*.xml注、mapper介面要麼要介面上加@Mapper註解、要麼在啟動類上加掃包註解：@MapperScan("com.springboot01.mapper")
（3）、三層事例：（思路、寫全springboot三要點。啟動器:pom.xml、啟動類：app.java、全域性屬性：application.yml）
專案結構圖：
A、建立maven工程、引入依賴:啟動器
pom.xml依賴、springboot叫啟動器、父工程 、jdk版本、web啟動器必引
注：不用的啟動器不能亂引。會出bug
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.day01springboot</groupId>
<artifactId>day01boot</artifactId>
<version>1.0-SNAPSHOT</version>
<!--父工程-->
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.4.RELEASE</version>
</parent>
<!--jdk版本-->
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<!--web啟動器-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!--mybatis依賴/啟動器-->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.3.2</version>
</dependency>
<!-- mysql 依賴 -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
</dependencies>
</project>B、編寫相關類，啟動類。。。(一個springboot只有一個啟動類)
App.java
package com.day01sboot;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
/**
* @ Author ：ShaoWei Sun.
* @ Date ：Created in 0:11 2018/12/1
*/
@MapperScan("com.day01sboot.mapper")//掃包、不用在一個個在mapper介面上加
@SpringBootApplication
public class App {
public static void main(String[] args) {
SpringApplication.run(App.class,args);
}
}
web層：controller/QueryController.java
package com.day01sboot.controller;
import com.day01sboot.pojo.User;
import com.day01sboot.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
/**
* @ Author ：ShaoWei Sun.
* @ Date ：Created in 9:38 2018/12/1
*/
@RestController
@RequestMapping("user")
public class QueryController {
@Autowired
private UserService userService;
@RequestMapping("query/{id}")
public User queryById(@PathVariable("id")Long id){
return userService.queryById(id);
}
}
Service層：service/UserService.java介面
package com.day01sboot.service;
import com.day01sboot.pojo.User;
/**
* @ Author ：ShaoWei Sun.
* @ Date ：Created in 9:44 2018/12/1
*/
public interface UserService {
User queryById(Long id);
}
Service層：service/UserServiceImpl.java實現類
package com.day01sboot.service.Impl;
import com.day01sboot.mapper.UserMapper;
import com.day01sboot.pojo.User;
import com.day01sboot.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
/**
* @ Author ：ShaoWei Sun.
* @ Date ：Created in 9:48 2018/12/1
*/
@Service
public class UserServiceImpl implements UserService {
@Autowired
private UserMapper userMapper;
@Override
public User queryById(Long id) {
return userMapper.queryById(id);
}
}持久層：mapper/UserMapper.java介面
package com.day01sboot.mapper;
import com.day01sboot.pojo.User;
/**
* @ Author ：ShaoWei Sun.
* @ Date ：Created in 0:55 2018/12/1
*/
public interface UserMapper {
User queryById(Long id);
}
對映檔案、存放SQL語句：resources/mappers/UserMapper.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">
<mapper namespace="com.day01sboot.mapper.UserMapper">
<resultMap type="User" id="userMap" autoMapping="true">
<id column="id" property="id"/>
</resultMap>
<sql id="commonSql">
id,user_name,password,name,age,sex,birthday,created,updated
</sql>
<select id="queryById" resultMap="userMap">
select <include refid="commonSql"></include> from tb_user where id = #{id}
</select>
<select id="findAllUsers" resultType="User">
select <include refid="commonSql"></include> from tb_user
</select>
<insert id="insertUser" useGeneratedKeys="true" keyColumn="id" keyProperty="id">
INSERT INTO tb_user (
user_name,
password,
name,
age,
sex,
birthday,
created,
updated
)
VALUES
(
#{userName},
#{password},
#{name},
#{age},
#{sex},
#{birthday},
NOW(),
NOW()
)
</insert>
<update id="updateUser">
UPDATE tb_user set
user_name = #{userName},
password = #{password},
name = #{name},
age = #{age},
sex = #{sex},
birthday = #{birthday},
updated = NOW()
WHERE
id = #{id}
</update>
<delete id="deleteUser">
delete from tb_user where
id = #{id}
</delete>
<!--
此處需要接收多個引數，有三種方式：
方式一：#{0} #{1}
方式二：#{param1} #{param2}
方式三：在介面方法的形參中加@Param註解指定名字，這裡通過#{名字}來接收引數，如果只有
一個引數，#{名字}可以自定義
-->
<select id="login" resultType="User">
select * from tb_user where user_name = #{userName} and password = #{password}
</select>
</mapper>實體類：pojo/User.java
package com.day01sboot.pojo;
import java.io.Serializable;
import java.util.Date;
public class User implements Serializable {
private static final long serialVersionUID = 1L;
private Long id;
// 使用者名稱
private String userName;
// 密碼
private String password;
// 姓名
private String name;
// 年齡
private Integer age;
// 性別，1男性，2女性
private Integer sex;
// 出生日期
private Date birthday;
// 建立時間
private Date created;
// 更新時間
private Date updated;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public Integer getSex() {
return sex;
}
public void setSex(Integer sex) {
this.sex = sex;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public Date getCreated() {
return created;
}
public void setCreated(Date created) {
this.created = created;
}
public Date getUpdated() {
return updated;
}
public void setUpdated(Date updated) {
this.updated = updated;
}
@Override
public String toString() {
return "User [id=" + id + ", userName=" + userName + ", password=" + password + ", name=" + name
+ ", age=" + age + ", sex=" + sex + ", birthday=" + birthday + ", created=" + created
+ ", updated=" + updated + "]";
}
}
資料庫：
C、springboot配置檔案、application.yml
mybatis:
type-aliases-package: com.day01sboot.pojo
mapper-locations: classpath:mappers/**/*.xml
configuration:
map-underscore-to-camel-case: true
spring:
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://localhost:3306/mybatis?useSSL=false
username: root
password: sswqzx
server:
port: 8080
《也學學大佬們、把原始碼傳到github
原始碼下載：https://github.com/sswqzx/day01boot
6、通用mapper....
極其方便的使用mybatis單表的增刪改查
支援單表、但不支援通用的多表聯合查詢
通用mapper使用：
繼承通用的Mapper<T>，必須指定泛型<T>
泛型(實體類)<T>的型別必須符合的要求
1、表名預設使用類名,駝峰轉下劃線(只對大寫字母進行處理),如UserInfo預設對應的表名為user_info。
2、表名可以使用@Table(name = "tableName")進行指定,對不符合第一條預設規則的可以通過這種方式指定表名.
3、表字段預設為Java物件的Field名字駝峰轉下劃線形式.
4、可以使用@Column(name = "fieldName")指定不符合第3條規則的欄位名
5、使用@Transient註解可以忽略欄位,新增該註解的欄位不會作為表字段使用.
6、建議一定是有一個@Id註解作為主鍵的欄位,可以有多個@Id註解的欄位作為聯合主鍵.
例項：
啟動類：pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/xsd/maven-4.0.0.xsd">
<parent>
<artifactId>SpringCloud01</artifactId>
<groupId>com.springclouds</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<groupId>com.springclouds</groupId>
<artifactId>user-service</artifactId>
<version>1.0-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
<groupId>tk.mybatis</groupId>
<artifactId>mapper-spring-boot-starter</artifactId>
</dependency>
</dependencies>
</project>啟動類：App.java
package com.springcloud;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import tk.mybatis.spring.annotation.MapperScan;
/**
* @ Author ：ShaoWei Sun.
* @ Date ：Created in 11:52 2018/11/30
*/
@SpringBootApplication
@MapperScan("com.springcloud.mapper")
public class App {
public static void main(String[] args) {
SpringApplication.run(App.class,args);
}
}
相關類：
controller/UserController.java
package com.springcloud.controller;
import com.springcloud.pojo.User;
import com.springcloud.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
/**
* @ Author ：ShaoWei Sun.
* @ Date ：Created in 11:14 2018/11/30
*/
@RequestMapping("/user")
@RestController
public class UserController {
@Autowired
private UserService userService;
@RequestMapping("/{id}")
public User queryById(@PathVariable("id")Long id){
return userService.queryById(id);
}
}
service/UserService.java
package com.springcloud.service;
import com.springcloud.mapper.UserMapper;
import com.springcloud.pojo.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
/**
* @ Author ：ShaoWei Sun.
* @ Date ：Created in 11:46 2018/11/30
*/
@Service
public class UserService {
@Autowired
private UserMapper userMapper;
public User queryById(Long id){
return userMapper.selectByPrimaryKey(id);
}
}
mapper/UserMapper
package com.springcloud.mapper;
import com.springcloud.pojo.User;
/**
* @ Author ：ShaoWei Sun.
* @ Date ：Created in 11:47 2018/11/30
*/
public interface UserMapper extends tk.mybatis.mapper.common.Mapper<User> {
}
pojo/User.java
package com.springcloud.pojo;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
import java.util.Date;
/**
* @ Author ：ShaoWei Sun.
* @ Date ：Created in 11:41 2018/11/30
*/
@Table(name = "tb_user")
public class User {
private static final Long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
// 使用者名稱
private String userName;
// 密碼
private String password;
// 姓名
private String name;
// 年齡
private Integer age;
// 性別，1男性，2女性
private Integer sex;
// 出生日期
private Date birthday;
// 建立時間
private Date created;
// 更新時間
private Date updated;
public static Long getSerialVersionUID() {
return serialVersionUID;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public Integer getSex() {
return sex;
}
public void setSex(Integer sex) {
this.sex = sex;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public Date getCreated() {
return created;
}
public void setCreated(Date created) {
this.created = created;
}
public Date getUpdated() {
return updated;
}
public void setUpdated(Date updated) {
this.updated = updated;
}
@Override
public String toString() {
return "User{" +
"id=" + id +
", userName='" + userName + '\'' +
", password='" + password + '\'' +
", name='" + name + '\'' +
", age=" + age +
", sex=" + sex +
", birthday=" + birthday +
", created=" + created +
", updated=" + updated +
'}';
}
}
全域性屬性：resources/application.yml
server:
port: 8081
spring:
datasource:
url: jdbc:mysql://localhost:3306/mybatis
username: root
password: sswqzx
mybatis:
type-aliases-package: com.springcloud.pojo