base64转MultipartFile工具类

工具类 

import org.springframework.core.io.Resource;
import org.springframework.web.multipart.MultipartFile;
import sun.misc.BASE64Decoder;

import java.io.*;
import java.nio.file.Path;

/**
 * base64转MultipartFile工具类
 * @author:caiLei
 */
public class BASE64DecodedMultipartFileUtil implements MultipartFile {
    private final byte[] imgContent;
    private final String header;

    public BASE64DecodedMultipartFileUtil(byte[] imgContent, String header) {
        this.imgContent = imgContent;
        this.header = header.split(";")[0];
    }

    @Override
    public String getName() {
        return System.currentTimeMillis() + Math.random() + "." + header.split("/")[1];
    }

    @Override
    public String getOriginalFilename() {
        return System.currentTimeMillis() + (int) Math.random() * 10000 + "." + header.split("/")[1];
    }

    @Override
    public String getContentType() {
        return header.split(":")[1];
    }

    @Override
    public boolean isEmpty() {
        return imgContent == null || imgContent.length == 0;
    }

    @Override
    public long getSize() {
        return imgContent.length;
    }

    @Override
    public byte[] getBytes() throws IOException {
        return imgContent;
    }

    @Override
    public InputStream getInputStream() throws IOException {
        return new ByteArrayInputStream(imgContent);
    }

    @Override
    public Resource getResource() {
        return null;
    }



    @Override
    public void transferTo(Path dest) throws IOException, IllegalStateException {

    }

    @Override
    public void transferTo(File dest) throws IOException, IllegalStateException {
        new FileOutputStream(dest).write(imgContent);
    }

    public static MultipartFile base64ToMultipart(String base64) {
        try {
            String[] baseStrs = base64.split(",");

            BASE64Decoder decoder = new BASE64Decoder();
            byte[] b = new byte[0];
            b = decoder.decodeBuffer(baseStrs[0]);

            for (int i = 0; i < b.length; ++i) {
                if (b[i] < 0) {
                    b[i] += 256;
                }
            }
            return new BASE64DecodedMultipartFileUtil(b, baseStrs[0]);
        } catch (IOException e) {
            ApiAssert.failure(ErrorCodeEnum.DECODE_PICTURE_ERROR);
            e.printStackTrace();
            return null;
        }
    }

}