SpringBoot中实现接收文件和对象

首先，我们需要添加SpringBoot Web和Multipart依赖，其pom.xml配置如下：

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-websocket</artifactId>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-test</artifactId>
    <scope>test</scope>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-tomcat</artifactId>
    <scope>provided</scope>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-aop</artifactId>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-security</artifactId>
</dependency>

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
</dependency>

<dependency>
    <groupId>commons-io</groupId>
    <artifactId>commons-io</artifactId>
</dependency>

<dependency>
    <groupId>javax.websocket</groupId>
    <artifactId>javax.websocket-api</artifactId>
    <version>1.1</version>
</dependency>

<dependency>
    <groupId>org.apache.tomcat.websocket</groupId>
    <artifactId>tomcat-websocket-api</artifactId>
    <version>8.5.4</version>
</dependency>

<dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-validator</artifactId>
</dependency>

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-context-support</artifactId>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-mail</artifactId>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-devtools</artifactId>
    <optional>true</optional>
</dependency>

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

<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-dbcp2</artifactId>
</dependency>

<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi-ooxml</artifactId>
    <version>4.1.0</version>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-freemarker</artifactId>
</dependency>

<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-collections4</artifactId>
</dependency>

<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-lang3</artifactId>
</dependency>

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.31</version>
</dependency>

<dependency>
    <groupId>commons-fileupload</groupId>
    <artifactId>commons-fileupload</artifactId>
    <version>1.4</version>
</dependency>

其中需要注意的是，multipart支持是在SpringBoot Web中默认开启的。接下来，我们分别讲解如何接收文件和对象。

一、接收文件

我们可以通过以下代码接收文件：

@PostMapping("/upload")
public @ResponseBody String upload(@RequestParam("file") MultipartFile file) {
    try {
        // 文件存储在应用根目录下的upload文件夹中
        File dir = new File("upload");
        if (!dir.exists()) {
            dir.mkdirs();
        }
        file.transferTo(new File(dir.getAbsolutePath(), file.getOriginalFilename()));
        return "Upload Success";
    } catch (IOException e) {
        e.printStackTrace();
        return "Upload Failed";
    }
}

在上面的代码中，我们首先通过@RequestParam注解标记要接收一个名为file的文件，然后将接收到的文件保存在应用根目录下的upload文件夹中。

二、接收对象

我们可以通过以下代码接收对象：

@PostMapping("/saveUser")
public @ResponseBody String saveUser(@RequestBody User user) {
    // TODO: 保存用户到数据库中
    return "Save Success";
}

public class User {
    private String name;
    private Integer age;
    // 省略getter和setter
}

在上面的代码中，我们通过@PostMapping注解标记要接收一个POST请求，然后通过@RequestBody注解将请求体中的JSON数据转换为User对象。这样，我们就能够接收到一个包含name和age属性的User对象，并对其进行后续处理。

至此，我们就完成了SpringBoot中实现接收文件和对象的完整攻略讲解。