文件断点续传

/*** 文件操作工具类*/
public class FileUtils {/*** 写入文件* @param target* @param src* @throws IOException*/public static void write(String target, InputStream src) throws IOException {OutputStream os = new FileOutputStream(target);byte[] buf = new byte[1024];int len;while (-1 != (len = src.read(buf))) {os.write(buf,0,len);}os.flush();os.close();}/*** 分块写入文件* @param target* @param targetSize* @param src* @param srcSize* @param chunks* @param chunk* @throws IOException*/public static void writeWithBlok(String target, Long targetSize, InputStream src, Long srcSize, Integer chunks, Integer chunk) throws IOException {RandomAccessFile randomAccessFile = new RandomAccessFile(target,"rw");randomAccessFile.setLength(targetSize);if (chunk == chunks - 1 && chunk != 0) {randomAccessFile.seek(chunk * (targetSize - srcSize) / chunk);} else {randomAccessFile.seek(chunk * srcSize);}byte[] buf = new byte[1024];int len;while (-1 != (len = src.read(buf))) {randomAccessFile.write(buf,0,len);}randomAccessFile.close();}/*** 生成随机文件名* @return*/public static String generateFileName() {return UUID.randomUUID().toString();}
}