springBoot整合mybatis、jsp 或 HTML

springBoot整合mybatis、jsp

Spring Boot的主要優點：

1：  為所有Spring開發者更快的入門；

2：  開箱即用，提供各種默認配置來簡化項目配置；

3：  內嵌式容器簡化Web項目；

 4：  沒有冗余代碼生成和XML配置的要求

 

本項目使用到的工具：

• 開發工具：Intellij IDEA 2018.1.4
• springboot:2.0.1.RELEASE
• jdk：1.8.0_40
• maven:3.3.9

 

開始搭建：

項目創建

 

 

 

 

 

 

 finish即可。

建好后的 項目結構：

 

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.dengwei</groupId>
    <artifactId>springdemo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>springdemo</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.1.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <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>
            <version>1.3.2</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <!--springBoot整合jsp-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-tomcat</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.tomcat.embed</groupId>
            <artifactId>tomcat-embed-jasper</artifactId>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>


</project>

 

 

 

 

 

我們先建一個controller層，寫一個簡單的類訪問一下：

 

 

 

 HelloSpringBootController:

package com.dengwei.springdemo.controller;

import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.HashMap;
import java.util.Map;

@RestController
public class HelloSpringBootController {
    @RequestMapping("/index")
    public String hello(){
        return "hello springBoot";
    }

    @RequestMapping("/hello")
    public Map<String,String> getMap(){
        HashMap<String, String> map = new HashMap<String,String>();
        map.put("key1","姓名");
        map.put("key2","年齡");
        map.put("key3","性別");
        return map;
    }

}

 

 下面我們啟動一下：

每一個springBoot項目中都有一個XXXAplication類，這個類就是springBoot的啟動類。

注意：因為我們前面添加了數據庫相關的依賴，但是我們還沒有具體配置，如果直接運行的話會報錯：

 

***************************
APPLICATION FAILED TO START
***************************
Description:
Failed to auto-configure a DataSource: 'spring.datasource.url' is not specified and no embedded datasource could be auto-configured.
Reason: Failed to determine a suitable driver class
Action:
Consider the following:
If you want an embedded database (H2, HSQL or Derby), please put it on the classpath.

 

If you have database settings to be loaded from a particular profile you may need to activate it (no profiles are currently active).

解決：

在@EnableAutoConfiguretion中添加   exclude= {DataSourceAutoConfiguration.class}，排除此類的autoconfig。啟動以后就可以正常運行。

 

 

 好的，啟動沒問題，我們下面正式進入mybatis與jsp的整合：

 

 建model層：

 

package com.dengwei.springdemo.model;

public class User {
    private Integer id;
    private String userName;
    private String password;

    public Integer getId() {
        return id;
    }

    public void setId(Integer 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;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", userName='" + userName + '\'' +
                ", password='" + password + '\'' +
                '}';
    }
}

 

 2：建mapper層：

   注意：我們這里的sql語句是通過注解的形式和接口寫在一起的，也可以通過xml的形式配置，可以見另外一篇博客：

 

 

package com.dengwei.springdemo.mapper;


import com.dengwei.springdemo.model.User;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;


public interface IUserMapper {

    @Select("SELECT id,user_name userName, pass_word password FROM user WHERE id = #{id}")
    User queryById(@Param("id") Integer id);
}

 

 3：建Service層：

 

package com.dengwei.springdemo.Service;


import com.dengwei.springdemo.mapper.IUserMapper;
import com.dengwei.springdemo.model.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class UserService {
    @Autowired
    private IUserMapper userMapper;
    public User queryUser(Integer id){
        return  userMapper.queryById(id);
    }
}

 

 4：控制層訪問：

 

package com.dengwei.springdemo.controller;


import com.dengwei.springdemo.Service.UserService;
import com.dengwei.springdemo.model.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

@Controller
@RequestMapping("/controller")
public class UserController {
    @Autowired
    private UserService userService;

    @RequestMapping("/user")
    @ResponseBody
    public User getUser(Integer id){
        User user = userService.queryUser(id);
        return user;
    }

}

 

 數據庫連接配置文件：

 

 

spring.mvc.view.prefix=/WEB-INF/jsp/
spring.mvc.view.suffix=.jsp 3 #jdbc相關 4 spring.datasource.url=jdbc:mysql://localhost:3306/floor_shop
spring.datasource.username=root 6 spring.datasource.password=admin 7 spring.datasource.driver-class-name=com.mysql.jdbc.Driver

 

 啟動springBoot:

 注意：前面我們排除了對數據庫相關的自動配置，現在我們配置了數據庫實體配置，所以把之前的排除要刪掉，並且多添加@MapperScan("mapper映射文件的地址")

 

package com.dengwei.springdemo;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;

@SpringBootApplication
@EnableAutoConfiguration
@MapperScan("com.dengwei.springdemo.mapper")
public class SpringdemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringdemoApplication.class, args);
    }
}

 

 好的直接啟動即可。上面我們簡單實現了數據庫的查詢，增刪改就自己取寫一寫吧。

 

下面我們看看springBoot整合jsp:

1、在原來的依賴中添加依賴：

 

 <!--對jsp訪問的支持-->
        <dependency>
            <groupId>org.apache.tomcat.embed</groupId>
            <artifactId>tomcat-embed-jasper</artifactId>
        </dependency>

 

2、跳轉頁面：

 

 springBoot整合thymeleaf：

 <!--模板引擎thmeleaf對HTML的支持-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>

跳轉頁面：

不用加前后綴，可以直接跳轉頁面：

 

關於thymeleaf的基礎使用參考：

https://www.jianshu.com/p/6953671d4645

 

 

             在我們第一次新建的HelloSpringBootController中 新建一個helloJsp()方法，注意：我們之前用的注解是@RestController ,這個注解相當於@Controller  +  @ResponseBody

  表示標注的類或則方法返回的都是json格式的，而我們這次需要訪問jsp頁面所以需要換成@Controller注解。在需要的返回json格式的方法上添加@ResponseBody，而不是整個類的所有方法都返回json格式。

 

 

下面我們看一下springBoot中的全局異常捕獲：

異常捕獲的核心標簽：@ControllerAdvice   +   @ExceptionHandler(RuntimeException.class)

package com.dengwei.springdemo.controller;

import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RequestMapping;

@ControllerAdvice
public class GlobalExceptionHandler {
    @ExceptionHandler(RuntimeException.class)
    @RequestMapping
    public String errorPage(){
        return "index";
    }
}

 

 

 好了，就先到這兒吧！