JAVA BLOB download read from the database-CodePudding

 @ Path ("/download ") 
@ POST 
@ Produces (MediaType APPLICATION_OCTET_STREAM) 
Public Response download (@ FormParam (dar) String dar) {
List List=ndsbBLOImpl. QueryFileById (dar); 
NdsbQyjbxxDTO dto=list. Get (0); 
String FJMC=dto. GetFjmc ();//attachment name 
Byte FJNR []=dto. GetFjnr ();//attachment content 
ResponseBuilder builder=Response. Ok (FJNR, "application/x - download; charset=utf-8"); 
Try {
Builder. The header (" the Content - the Disposition ", "legislation; Filename="+ URLEncoder. Encode (FJMC," utf-8 ") + ""); 
} the catch (UnsupportedEncodingException e) {
e.printStackTrace(); 
} 
The Response the Response=builder. The build (); 
return response; 
}

Download file has been 1 KB, open the display as follows:

CodePudding user response:

You should read from a database is a byte array, use the form of a stream to return

 @ Path ("/download ") 
@ POST 
@ Produces (MediaType APPLICATION_OCTET_STREAM) 
Public Response download (@ FormParam (dar) String dar) {
List List=ndsbBLOImpl. QueryFileById (dar); 
NdsbQyjbxxDTO dto=list. Get (0); 
String FJMC=dto. GetFjmc ();//attachment name 
Byte FJNR []=dto. GetFjnr ();//attachment content 
StreamingOutput stream=new StreamingOutput () {//implementation stream 
@ Override 
Public void write (OutputStream output) throws IOException, WebApplicationException {
Try {
The output. The write (FJNR);//read the database output to the stream of bytes 
} the catch (Exception e) {
Throw new WebApplicationException (e); 
} 
} 
}; 
//ResponseBuilder builder=Response. Ok (FJNR, "application/x - download; charset=utf-8"); 
ResponseBuilder builder=Response. Ok (stream);//the stream back to 
Try {
Builder. The header (" the Content - the Disposition ", "legislation; Filename="+ URLEncoder. Encode (FJMC," utf-8 ") + ""); 
} the catch (UnsupportedEncodingException e) {
e.printStackTrace(); 
} 
The Response the Response=builder. The build (); 
return response; 
}