Managing HTTP Response Header Lines

JSP Tutorials - Herong's Tutorial Examples

∟Managing HTTP Response Header Lines

This chapter provides tutorial notes and example codes on HTTP response header lines. Topics include what is an HTTP response; what are response header line; controlling response header lines; viewing entire HTTP response message; 'page contentType' directive element; response object methods to change header lines; returning non-HTML response body; returning attachments for downloads.

These sections are omitted from this Web preview version. To view the full content, see information on how to obtain the full version this book.

What Is HTTP Response

HTTP Response Header Lines

Controlling Response Header Lines

Viewing Response Header Lines

Response Header Lines of Static Files

Response Header Lines Controlled by "page" Directive

Response Header Lines Controlled by response Object

Accessing File System from JSP Pages

Returning non-HTML Response Body

Returning Attachments for Web Download

Conclusions:

HTTP response contains header lines and a body. A full empty line is required to separate header lines and the body.
The most important response header lines are Content-Type and Content-Length.
"page contentType" directive elements can be used to set the Content-Type header line.
response.setContentType() and response.setContentLength() can be used to set Content-Type and Content-Length header lines.
response.addheader() and addHeader() can be used to set any types of header lines.
Value of Content-Length header line must match the number of bytes in the response body.
"Content-disposition" header line can be used to attachment as Web downloads.