Servlet tips --sending HTML information

最新推荐文章于 2021-07-16 20:38:27 发布

最新推荐文章于 2021-07-16 20:38:27 发布 · 74 阅读

文章标签：

#HTML #Servlet #Web #XML

本文详细介绍了Servlet中响应处理的基础知识，包括设置响应类型、缓冲区管理、状态码设定、HTTP头设置、请求重定向及错误页面配置等内容，并提供了长期运行Servlet的错误检查建议。

1. Response basics:

public void ServletResponse.setContentType(String); //content type of response

pubic PrintWriter ServletResponse.getWriter(); //charactor output

public ServletOutStream ServletResponse.getOutputStream(); //Stream output

2. Response buffering

ServletResponse.setBufferSize(int); //set buffer size

ServletResponse.getBufferSize(int); //get buffer size

ServletResponse.isCommited() // is sent?

ServletResponse.reset(); // reset,clear all buffer content

ServletResponse.flushBuffer(); //sent

3.Status Codes : public static final int fields of HttpServletResponse

HttpServletResponse.sendStatus(in t sc); //set status, should be called before committed.

HttpServletResponse.sendError(.., ..), //send error and clean buffer.

4. setting a Http Header: HttpServletResponse.setHeader(..,..) and so on.

5. redirecting a request:

HttpServletResponse.setStatus(HttpServletResponse.SC_MOVED_TEMPORARILY); HttpServletResponse.setHeader("Location", site)

EQUALS TO

HttpServletResponse.sendRedirect(site);

6. Error Pages configured in web.xml:

<error-page> <error-code>code</error-code><location>/error.html</location></error-page>

7. Logging: GenericServlet.log(String, [...]);

8. Configure exception page in web.xml: <error-page> <exception-type> class </exception-type> <location>./pathname</location></error-page>

9. dynamically creating a exception(error) page : mainly using request.getAttribute("javax.servlet.error.status_code"); request.getAttribute("javax.servlet.error.message"); request.getAttribute("javax.servlet.error.exception_type");

10. A long-running servlet that doesn't mind committing the response early should call checkError() regularly to determine if it can halt processing before completion.