Beispiel Upload file mit Spring Boot

<?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>org.o7planning</groupId>
    <artifactId>SpringBootFileUpload</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>SpringBootFileUpload</name>
    <description>Spring Boot + File Upload Example</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.0.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-thymeleaf</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

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

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

</project>

package org.o7planning.sbfileupload;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class SpringBootFileUploadApplication {

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

spring.servlet.multipart.max-file-size=5MB
spring.servlet.multipart.max-request-size=5MB

package org.o7planning.sbfileupload.form;

import org.springframework.web.multipart.MultipartFile;

public class MyUploadForm {

    private String description;

    // Upload files.
    private MultipartFile[] fileDatas;

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public MultipartFile[] getFileDatas() {
        return fileDatas;
    }

    public void setFileDatas(MultipartFile[] fileDatas) {
        this.fileDatas = fileDatas;
    }

}

package org.o7planning.sbfileupload.controller;

import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.util.ArrayList;
import java.util.List;

import javax.servlet.http.HttpServletRequest;

import org.o7planning.sbfileupload.form.MyUploadForm;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.multipart.MultipartFile;

@Controller
public class MyFileUploadController {

   @RequestMapping(value = "/")
   public String homePage() {

      return "index";
   }

   // GET: Show upload form page.
   @RequestMapping(value = "/uploadOneFile", method = RequestMethod.GET)
   public String uploadOneFileHandler(Model model) {

      MyUploadForm myUploadForm = new MyUploadForm();
      model.addAttribute("myUploadForm", myUploadForm);

      return "uploadOneFile";
   }

   // POST: Do Upload
   @RequestMapping(value = "/uploadOneFile", method = RequestMethod.POST)
   public String uploadOneFileHandlerPOST(HttpServletRequest request, //
         Model model, //
         @ModelAttribute("myUploadForm") MyUploadForm myUploadForm) {

      return this.doUpload(request, model, myUploadForm);

   }

   // GET: Show upload form page.
   @RequestMapping(value = "/uploadMultiFile", method = RequestMethod.GET)
   public String uploadMultiFileHandler(Model model) {

      MyUploadForm myUploadForm = new MyUploadForm();
      model.addAttribute("myUploadForm", myUploadForm);

      return "uploadMultiFile";
   }

   // POST: Do Upload
   @RequestMapping(value = "/uploadMultiFile", method = RequestMethod.POST)
   public String uploadMultiFileHandlerPOST(HttpServletRequest request, //
         Model model, //
         @ModelAttribute("myUploadForm") MyUploadForm myUploadForm) {

      return this.doUpload(request, model, myUploadForm);

   }

   private String doUpload(HttpServletRequest request, Model model, //
         MyUploadForm myUploadForm) {

      String description = myUploadForm.getDescription();
      System.out.println("Description: " + description);

      // Root Directory.
      String uploadRootPath = request.getServletContext().getRealPath("upload");
      System.out.println("uploadRootPath=" + uploadRootPath);

      File uploadRootDir = new File(uploadRootPath);
      // Create directory if it not exists.
      if (!uploadRootDir.exists()) {
         uploadRootDir.mkdirs();
      }
      MultipartFile[] fileDatas = myUploadForm.getFileDatas();
      //
      List<File> uploadedFiles = new ArrayList<File>();
      List<String> failedFiles = new ArrayList<String>();

      for (MultipartFile fileData : fileDatas) {

         // Client File Name
         String name = fileData.getOriginalFilename();
         System.out.println("Client File Name = " + name);

         if (name != null && name.length() > 0) {
            try {
               // Create the file at server
               File serverFile = new File(uploadRootDir.getAbsolutePath() + File.separator + name);

               BufferedOutputStream stream = new BufferedOutputStream(new FileOutputStream(serverFile));
               stream.write(fileData.getBytes());
               stream.close();
               //
               uploadedFiles.add(serverFile);
               System.out.println("Write file: " + serverFile);
            } catch (Exception e) {
               System.out.println("Error Write file: " + name);
               failedFiles.add(name);
            }
         }
      }
      model.addAttribute("description", description);
      model.addAttribute("uploadedFiles", uploadedFiles);
      model.addAttribute("failedFiles", failedFiles);
      return "uploadResult";
   }

}

<div  xmlns:th="http://www.thymeleaf.org"
   style="border:1px solid #ccc;padding:5px;">
 
   <a th:href="@{/uploadOneFile}">Upload One File</a>
   
   &nbsp;|&nbsp;
   
   <a th:href="@{/uploadMultiFile}">Upload Multi File</a>
   
   
 </div>

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">

   <head>
      <meta charset="UTF-8">
      <title>Spring Boot File Upload Example</title>
   </head>
   
   <body>
      <th:block th:include="/_menu"></th:block>
      
      <h3>Spring Boot File Upload Example</h3>
      
      <ul>
        <li><a th:href="@{/uploadOneFile}">Upload One File Example</a></li>
        <li><a th:href="@{/uploadMultiFile}">Upload Multiple Files Example</a></li>
      </ul>
      
   </body>
</html>

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">

   <head>
      <meta charset="UTF-8">
      <title>Upload One File</title>
   </head>
  
   <body>
      <th:block th:include="/_menu"></th:block>
      
      <h3>Upload One File:</h3>
      
      <!-- MyUploadForm -->
      
      <form th:object="${myUploadForm}" method="POST"
         action="" enctype="multipart/form-data">
         Description:
         <br>
         <input th:field="*{description}" style="width:300px;"/>                
         <br/><br/>  
         File to upload: <input th:field="*{fileDatas}" type="file"/>
         <br />  
         <input type="submit" value="Upload">
      </form>
      
   </body>
</html>

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">

   <head>
      <meta charset="UTF-8">
      <title>Upload Multi File</title>
   </head>
   
   <body>
      <th:block th:include="/_menu"></th:block>
      <h3>Upload Multiple File:</h3>
      
      <!-- MyUploadForm -->
      <form th:object="${myUploadForm}" method="POST"
         action="" enctype="multipart/form-data">
         Description:
         <br>
         <input th:field="*{description}" style="width:300px;"/>                
         <br/><br/>                 
         File to upload (1): <input th:field="*{fileDatas}" type="file"/><br />      
         File to upload (2): <input th:field="*{fileDatas}" type="file"/><br />    
         File to upload (3): <input th:field="*{fileDatas}" type="file"/><br />    
         File to upload (4): <input th:field="*{fileDatas}" type="file"/><br />    
         File to upload (5): <input th:field="*{fileDatas}" type="file"/><br />    
         <input type="submit" value="Upload">
      </form>
      
   </body>
</html>

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">
   <head>
      <meta charset="UTF-8">
      <title>Upload Result</title>
   </head>
   
   <body>
      <th:block th:include="/_menu"></th:block>
      
      Description: <span th:utext="${description}"></span>
      <br/>
      <h3>Uploaded Files:</h3>
      
      <ul th:each="file : ${uploadedFiles}">
         <li th:utext="${file}"></li>  
      </ul>      
      
      <h3>Failed:</h3>
      <ul th:each="file : ${failedFiles}">
         <li style="color:red;" th:utext="${file}"></li>  
      </ul>
      
   </body>
   
</html>