1.Spring自带方法,定义输出流就可以写入文件

final OutputStream os;                os = new FileOutputStream(new File("300.zip"));                FileCopyUtils.copy(blob.getBinaryStream(), os);

2.转成byte[]后写入

Blob blob = rs.getBlob("FSTREAM");                ByteArrayOutputStream swapStream = new ByteArrayOutputStream();                InputStream inputStream = blob.getBinaryStream();                byte[] buff = new byte[100]; //buff用于存放循环读取的临时数据                int rc = 0;                while ((rc = inputStream.read(buff, 0, 100)) > 0) {                    swapStream.write(buff, 0, rc);                }                byte[] fStreamByte = swapStream.toByteArray(); //in_b为转换之后的结果                final OutputStream os;                os = new FileOutputStream(new File("300.zip"));                os.write(fStreamByte);                os.close();