Multipart file upload class.

UploadService.java

import java.awt.image.BufferedImage;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;

import javax.imageio.ImageIO;

import org.apache.commons.codec.digest.DigestUtils;
import org.apache.commons.io.FilenameUtils;
import org.apache.commons.io.IOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.ApplicationContext;
import org.springframework.core.env.Environment;
import org.springframework.core.io.Resource;
import org.springframework.stereotype.Service;
import org.springframework.web.multipart.MultipartFile;

import com.fasterxml.jackson.databind.ObjectMapper;

@Service
public class UploadServiceImpl implements UploadService {
	private static final Logger logger = LoggerFactory.getLogger(UploadServiceImpl.class);

	@Autowired private ObjectMapper mapper;
	@Autowired private Environment environment;
	@Autowired private ApplicationContext applicationContext;

	@Value("${upload.path}") private String uploadPath;
	@Value("${upload.url}") private String uploadUrl;

	public class UploadedFile {
		private String url;
		private String hash;

		private Integer width;
		private Integer height;

		public UploadedFile(String url, String hash, Integer width, Integer height) {
			this.url=url;
			this.hash=hash;
			this.width=width;
			this.height=height;
		}

		public String getHash() {
			return hash;
		}
		public String getUrl() {
			return url;
		}
		public Integer getHeight() {
			return height;
		}
		public Integer getWidth() {
			return width;
		}
	}

	@Override
	public UploadedFile uploadImageFile(MultipartFile multipartFile) {
		String extension=FilenameUtils.getExtension(multipartFile.getOriginalFilename());
		BufferedOutputStream bos=null;
		InputStream is=null;

		try {
			File directory=new File(uploadPath);
			if(!directory.exists() && !directory.mkdirs()) { //경로 없으면 생성
				return null;
			}

			String hash=DigestUtils.md5Hex(multipartFile.getBytes());
			Resource outputResource=applicationContext.getResource("file:"+uploadPath+"/"+hash+"."+extension);
			File outputFile=outputResource.getFile();

			BufferedImage bImg=ImageIO.read(multipartFile.getInputStream()); //ImageIO는 stream을 닫아버려서 stream 재활용 불가.
			Integer width=bImg.getWidth();
			Integer height=bImg.getHeight();

			is=multipartFile.getInputStream();
			bos=new BufferedOutputStream(new FileOutputStream(outputFile));
			IOUtils.copy(is, bos);

			return new UploadedFile(uploadUrl+"/"+outputFile.getName(), hash, width, height);
		} catch(Exception e) {
			logger.error("Error on upload image", e);
			return null;
		} finally {
			IOUtils.closeQuietly(bos);
			IOUtils.closeQuietly(is);
		}
	}
}