[二十]SpringBoot 之（多）文件上傳

時間 2019-11-14

原文原文鏈接

（1）新建maven Java projecthtml

新建一個名稱爲spring-boot-fileuploadmaven java項目java

（2）在pom.xml加入相應依賴；web

<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>me.shijunjie</groupId>
    <artifactId>spring-boot-fileuploadmaven</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>spring-boot-fileuploadmaven</name>
    <url>http://maven.apache.org</url>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.3.4.RELEASE</version>
    </parent>

    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- thmleaf模板依賴. -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
    </dependencies>

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

            <!-- <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin 
                </artifactId> <dependencies> springloaded hotdeploy <dependency> <groupId>org.springframework</groupId> 
                <artifactId>springloaded</artifactId> <version>1.2.4.RELEASE</version> </dependency> 
                </dependencies> <executions> <execution> <goals> <goal>repackage</goal> </goals> 
                <configuration> <classifier>exec</classifier> </configuration> </execution> 
                </executions> </plugin> -->

            <!-- java編譯插件 -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

（3）新建一個表單頁面（這裏使用thymeleaf）spring

在src/main/resouces新建templates(若是看過博主以前的文章，應該知道，templates是spring boot存放模板文件的路徑)，在templates下新建一個file.html:apache

<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
    xmlns:th="http://www.thymeleaf.org"
    xmlns:sec="http://www.thymeleaf.org/thymeleaf-extras-springsecurity3">
<head>
<title>Hello World!</title>
</head>
<body>
    <form method="POST" enctype="multipart/form-data" action="/upload">
        <p>
            文件：<input type="file" name="file" />
        </p>
        <p>
            <input type="submit" value="上傳" />
        </p>
    </form>
</body>
</html>

（4）編寫controller;app

package me.shijunjie.controller;

import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.List;

import javax.servlet.http.HttpServletRequest;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.multipart.MultipartHttpServletRequest;


@Controller
public class FileUploadController {
    //訪問路徑爲：http://127.0.0.1:8080/file
    @RequestMapping("/file")
    public String file(){
        return "/file";
    }
    
    @RequestMapping("/mutifile")
    public String mutifile(){
        return "/mutifile";
    }

    @RequestMapping("/upload")
    @ResponseBody
    public String handleFileUpload(@RequestParam("file")MultipartFile file){
        if(!file.isEmpty()){
            try {
                BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream(new File(file.getOriginalFilename())));
                out.write(file.getBytes());
                out.flush();
                out.close();
            }catch(FileNotFoundException e) {
                e.printStackTrace();
                return "上傳失敗,"+e.getMessage();
            }catch (IOException e) {
                e.printStackTrace();
                return "上傳失敗,"+e.getMessage();
            }

            return "上傳成功";

        }else{

            return "上傳失敗，由於文件是空的.";

        }
    }

    /**

     * 多文件具體上傳時間，主要是使用了MultipartHttpServletRequest和MultipartFile

     * @param request

     * @return

     */

    @RequestMapping(value="/batch/upload", method=RequestMethod.POST) 
    public @ResponseBody 
    String handleFileUpload(HttpServletRequest request){ 
        List<MultipartFile> files =((MultipartHttpServletRequest)request).getFiles("file"); 
        MultipartFile file = null;
        BufferedOutputStream stream = null;
        for (int i =0; i< files.size(); ++i) { 
            file = files.get(i); 
            if (!file.isEmpty()) { 
                try { 
                    byte[] bytes = file.getBytes(); 
                    stream = 
                            new BufferedOutputStream(new FileOutputStream(new File(file.getOriginalFilename()))); 
                    stream.write(bytes); 
                    stream.close(); 
                } catch (Exception e) { 
                    stream =  null;
                    return "You failed to upload " + i + " =>" + e.getMessage(); 
                } 
            } else { 
                return "You failed to upload " + i + " becausethe file was empty."; 
            } 
        } 
        return "upload successful"; 

    } 
}

（6）對上傳的文件作一些限制；maven

package me.shijunjie.spring_boot_fileuploadmaven;

import javax.servlet.MultipartConfigElement;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.context.embedded.MultipartConfigFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;

@SpringBootApplication
@ComponentScan(value="me.shijunjie")
public class App 
{
    @Bean 
    public MultipartConfigElement multipartConfigElement() { 
        MultipartConfigFactory factory = new MultipartConfigFactory();
        //// 設置文件大小限制 ,超了，頁面會拋出異常信息，這時候就須要進行異常信息的處理了;
        factory.setMaxFileSize("128KB"); //KB,MB
        /// 設置總上傳數據總大小
        factory.setMaxRequestSize("256KB"); 
        //Sets the directory location wherefiles will be stored.
        //factory.setLocation("路徑地址");
        return factory.createMultipartConfig(); 
    } 

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