springmvc上传和下载文件

版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/zhaozhirongfree1111/article/details/84590947

• pom依赖

 <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>1.7</maven.compiler.source>
    <maven.compiler.target>1.7</maven.compiler.target>
    <spring.version>4.2.5.RELEASE</spring.version>
    <slf4j.version>1.7.6</slf4j.version>
  </properties>

  <dependencies>
    <!-- 文件上传相关JAR包 -->
    <dependency>
      <groupId>commons-io</groupId>
      <artifactId>commons-io</artifactId>
      <version>1.3.2</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-web</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <!-- LOG -->
    <dependency>
      <groupId>org.slf4j</groupId>
      <artifactId>slf4j-api</artifactId>
      <version>${slf4j.version}</version>
    </dependency>
  </dependencies>

• controller

import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartFile;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.UUID;

/**
 * Created by zhaozhirong on 2018/11/27.
 */
@Controller
@RequestMapping("/file")
public class FileController {

    private final Logger logger = LoggerFactory.getLogger(FileController.class);
    @ResponseBody
    @RequestMapping("upload")
    public JsonResp uploadFile(
            @RequestParam(value = "file", required = true) MultipartFile file
    ) {
        JsonResp resp = new JsonResp();
        File uploadFile = null;
        InputStream is = null;
        FileOutputStream fos = null;
        try {
            if (file.isEmpty()) {
                resp.setRespInfo(JsonResp.FAIL, "Upload file can not be null or empty!");
                return resp;
            }
            is = file.getInputStream();
            File uploadDir = UploadUtil.getUploadDir();
            uploadFile = new File(uploadDir, UUID.randomUUID().toString());
            logger.debug("Upload file is: {}", uploadFile.getAbsolutePath());
            fos = new FileOutputStream(uploadFile);
            IOUtils.copy(is, fos);
            fos.flush();
            resp.setRespInfo(JsonResp.FAIL,"success");
            resp.setResult(uploadDir.getAbsolutePath());
        } catch (Exception e) {
            logger.error(e.getMessage(), e);
            resp.setRespInfo(JsonResp.FAIL, e.getMessage());
            return resp;
        } finally {
            if (fos != null) {
                try {
                    fos.close();
                } catch (IOException e) {
                    logger.error(e.getMessage(), e);
                    resp.setRespInfo(JsonResp.FAIL, e.getMessage());
                }
            }
            if (is != null) {
                try {
                    is.close();
                } catch (IOException e) {
                    logger.error(e.getMessage(), e);
                    resp.setRespInfo(JsonResp.FAIL, e.getMessage());
                }
            }
        }

        return resp;
    }

    @RequestMapping("/download")
    public ResponseEntity<byte[]> export(String filePath) throws IOException {
        HttpHeaders headers = new HttpHeaders();
        headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
        String fileName = filePath.substring(filePath.lastIndexOf(File.separator) + 1);
        headers.setContentDispositionFormData("attachment", fileName);
        return new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(new File(filePath)),
                headers, HttpStatus.CREATED);
    }
}

• 辅助类

/**
 * Created by qiuyujiang on 2018/11/15.
 */
public class JsonResp {

    public final static Integer SUCCESS = 0;
    public final static Integer FAIL = 1;

    private Integer code;
    private String message;
    private Object result;

    public void setRespInfo(int code, String message) {
        this.code = code;
        this.message = message;
    }

    public Integer getCode() {
        return code;
    }

    public void setCode(Integer code) {
        this.code = code;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    public Object getResult() {
        return result;
    }

    public void setResult(Object result) {
        this.result = result;
    }
}

• html

<!DOCTYPE html>
<html lang="en" xmlns="http://www.w3.org/1999/html">
<head>
    <meta charset="UTF-8">
    <link rel="icon" href="data:;base64,=">
    <title></title>
</head>
<body>
        <form id="file" enctype="multipart/form-data">
            文件:<input type="file" name="file"/><input type="button" onclick="test('file');" value="上传"/>
        </form>
</body>
</html>
<script src="/js/jquery-1.11.3.min.js"></script>
<script>
function test(formId) {
    var formData = new FormData($('#'+formId)[0]);
    $.ajax({
        type: 'POST',
        url: '/file/upload',
        data: formData,
        cache: false,
        processData: false,
        contentType: false,
        success: function(resp) {
            console.log(resp);
        }
    });
}
</script>