Functions and parameters of Response. setContentType ()

Response. setContentType (MIME_TYPE) is used to differentiate different types of data in the client browser. Based on the MIME_TYPE, different program embedding modules in the browser are called to process the corresponding data.

For example, the WEB browser uses the MIME_TYPE to determine whether the file is a GIF image or a JSON string.

The MIME_TYPE is fully defined in the Tomcat installation directory \ conf \ web. xml. The type in the XML node is mime-mapping.

Common types include:

Text/html

Text/htm

Text/css

Image/bmp

Image/gif

Image/jpeg

Text/plain

Text/javascript

Video/mp4

Video/mpeg

Application/pdf

Image/png

Application/rtf

Application/zip

The Response. setContentType () method is used to set the content type sent to the client. At this time, the Response content has not been returned to the client browser. The given content type can include a description of character encoding, for example: text/html: charset = UTF-8, if this method is called before the getWriter () method is called, then, the response encoding will only be set from the given content type. If the getWriter () method is called, the response character encoding is not set.

You can only set the Content-type object header in HTTP. In Servlet, it is customary to first set the request and response content types and encoding methods:

Response. setContentType ("text/html; charset = UTF-8 ");

Request. setCharacterEncoding ("UTF-8 ");