base64和在线url链接转为MultipartFile
1.base64转为MultipartFile
import org.apache.commons.codec.binary.Base64;
import org.springframework.web.multipart.MultipartFile;
import java.io.*;
public class Base64ToMultipartFileConverter {
public static MultipartFile base64ToMultipartFile(String base64) {
//base64编码后的图片有头信息所以要分离出来 [0]data:image/png;base64, 图片内容为索引[1]
String[] baseStrs = base64.split(",");
//取索引为1的元素进行处理
byte[] b = Base64.decodeBase64(baseStrs[1]);
for (int i = 0; i < b.length; ++i) {
if (b[i] < 0) {
b[i] += 256;
}
}
//处理过后的数据通过Base64DecodeMultipartFile转换为MultipartFile对象
return new Base64DecodeMultipartFile(b, baseStrs[0]);
}
}
class Base64DecodeMultipartFile implements MultipartFile {
private final byte[] imgContent;
private final String header;
public Base64DecodeMultipartFile(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 void transferTo(File dest) throws IOException, IllegalStateException {
new FileOutputStream(dest).write(imgContent);
}
}
2.url转为MultipartFile
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.util.StreamUtils;
import java.net.URL;
import java.net.URLConnection;
import java.io.InputStream;
import java.io.IOException;
import java.io.ByteArrayInputStream;
@Component
@Slf4j
public class UrlToMultipartFileConverter {
public static MultipartFile convert(String url) {
URLConnection connection = null;
InputStream inputStream = null;
byte[] bytes = null;
try {
connection = new URL(url).openConnection();
inputStream = connection.getInputStream();
bytes = StreamUtils.copyToByteArray(inputStream);
} catch (Exception e) {
log.error(e.toString());
}
String contentType = connection.getContentType();
String[] contentTypes = contentType.split("/");
String filename = "file." + contentTypes[1];
return new ByteArrayMultipartFile(bytes, filename, contentType);
}
private static class ByteArrayMultipartFile implements MultipartFile {
private final byte[] content;
private final String name;
private final String originalFilename;
private final String contentType;
public ByteArrayMultipartFile(byte[] content, String name, String contentType) {
this.content = content;
this.name = name;
this.originalFilename = name;
this.contentType = contentType;
}
@Override
public String getName() {
return name;
}
@Override
public String getOriginalFilename() {
return originalFilename;
}
@Override
public String getContentType() {
return contentType;
}
@Override
public boolean isEmpty() {
return content.length == 0;
}
@Override
public long getSize() {
return content.length;
}
@Override
public byte[] getBytes() throws IOException {
return content;
}
@Override
public InputStream getInputStream() throws IOException {
return new ByteArrayInputStream(content);
}
@Override
public void transferTo(java.io.File file) throws IOException, IllegalStateException {
throw new UnsupportedOperationException();
}
}
}