【SpringMvc】SpringMvc图片下载的几种返回方式

男娘i 2022-11-21 11:47 205阅读 0赞

### 文章目录 ###

*  代码
 *  扩展

# 代码 #

import org.apache.tomcat.util.http.fileupload.FileUtils;
    import org.springframework.core.io.ByteArrayResource;
    import org.springframework.core.io.FileSystemResource;
    import org.springframework.core.io.Resource;
    import org.springframework.http.MediaType;
    import org.springframework.http.ResponseEntity;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.ResponseBody;
    import org.springframework.web.bind.annotation.RestController;
    
    
    import javax.imageio.ImageIO;
    import java.awt.image.BufferedImage;
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.IOException;
    import java.nio.file.Files;
    
    /**
     * @author: Curiosity
     * @Date: 2020/11/1 15:44
     * @Description: SpringMvc返回文件的几种方式
     */
    @RestController
    public class ImageController {
        
        private static final String PATH = "D:\\360MoveData\\Users\\Desktop\\QQ截图20190608195316.png";
    
        /**
         * 通过byte 数组获取图片
         *
         * @return
         * @throws IOException
         */
    
        @RequestMapping(value = "/image", produces = MediaType.IMAGE_JPEG_VALUE)
        public byte[] getImageByByteArray() throws IOException {
        
            File file = new File(PATH);
            try (FileInputStream inputStream = new FileInputStream(file)) {
        
                byte[] bytes = new byte[inputStream.available()];
                inputStream.read(bytes, 0, inputStream.available());
                return bytes;
            }
    
        }
    
        /**
         * 通过FileSystemResource返回图片
         *
         * @return
         * @throws IOException
         */
        @RequestMapping(value = "/image1", produces = MediaType.IMAGE_JPEG_VALUE)
        public ResponseEntity<Resource> getImageByFileSystemResource() throws IOException {
        
            File file = new File(PATH);
            FileSystemResource fileSystemResource = new FileSystemResource(file);
            return ResponseEntity.ok(fileSystemResource);
        }
    
    
        /**
         * 通过ByteArrayResource返回图片
         *
         * @return
         * @throws IOException
         */
        @RequestMapping(value = "/image2", produces = MediaType.IMAGE_JPEG_VALUE)
        public ResponseEntity<Resource> getImageByByteArrayResource() throws IOException {
        
            File file = new File(PATH);
            ByteArrayResource byteArrayResource = new ByteArrayResource(Files.readAllBytes(file.toPath()));
            return ResponseEntity.ok(byteArrayResource);
        }
    
    
    }

# 扩展 #

> 可以通过`BufferedImage`做为返回值去返回图片,前提是需要加入`BufferedImageHttpMessageConverter` 转换器

@Bean 
    public BufferedImageHttpMessageConverter bufferedImageHttpMessageConverter(){
         
    		return new BufferedImageHttpMessageConverter(); 
    }