httpservlet.html

j2ee api,很好的api。我这现在有

<CODE>protected &nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../javax/servlet/http/HttpServlet.html#doOptions(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)">doOptions</A></B>(<A HREF="../../../javax/servlet/http/HttpServletRequest.html" title="interface in javax.servlet.http">HttpServletRequest</A>&nbsp;req,
          <A HREF="../../../javax/servlet/http/HttpServletResponse.html" title="interface in javax.servlet.http">HttpServletResponse</A>&nbsp;resp)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Called by the server (via the <code>service</code> method)
 to allow a servlet to handle a OPTIONS request.

 </TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>protected &nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../javax/servlet/http/HttpServlet.html#doPost(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)">doPost</A></B>(<A HREF="../../../javax/servlet/http/HttpServletRequest.html" title="interface in javax.servlet.http">HttpServletRequest</A>&nbsp;req,
       <A HREF="../../../javax/servlet/http/HttpServletResponse.html" title="interface in javax.servlet.http">HttpServletResponse</A>&nbsp;resp)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Called by the server (via the <code>service</code> method)
 to allow a servlet to handle a POST request.

 </TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>protected &nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../javax/servlet/http/HttpServlet.html#doPut(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)">doPut</A></B>(<A HREF="../../../javax/servlet/http/HttpServletRequest.html" title="interface in javax.servlet.http">HttpServletRequest</A>&nbsp;req,
      <A HREF="../../../javax/servlet/http/HttpServletResponse.html" title="interface in javax.servlet.http">HttpServletResponse</A>&nbsp;resp)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Called by the server (via the <code>service</code> method)
 to allow a servlet to handle a PUT request.

 </TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>protected &nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../javax/servlet/http/HttpServlet.html#doTrace(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)">doTrace</A></B>(<A HREF="../../../javax/servlet/http/HttpServletRequest.html" title="interface in javax.servlet.http">HttpServletRequest</A>&nbsp;req,
        <A HREF="../../../javax/servlet/http/HttpServletResponse.html" title="interface in javax.servlet.http">HttpServletResponse</A>&nbsp;resp)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Called by the server (via the <code>service</code> method)
 to allow a servlet to handle a TRACE request.

 </TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>protected &nbsp;long</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../javax/servlet/http/HttpServlet.html#getLastModified(javax.servlet.http.HttpServletRequest)">getLastModified</A></B>(<A HREF="../../../javax/servlet/http/HttpServletRequest.html" title="interface in javax.servlet.http">HttpServletRequest</A>&nbsp;req)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Returns the time the <code>HttpServletRequest</code>
 object was last modified,
 in milliseconds since midnight January 1, 1970 GMT.
 </TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>protected &nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../javax/servlet/http/HttpServlet.html#service(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)">service</A></B>(<A HREF="../../../javax/servlet/http/HttpServletRequest.html" title="interface in javax.servlet.http">HttpServletRequest</A>&nbsp;req,
        <A HREF="../../../javax/servlet/http/HttpServletResponse.html" title="interface in javax.servlet.http">HttpServletResponse</A>&nbsp;resp)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Receives standard HTTP requests from the public
 <code>service</code> method and dispatches
 them to the <code>do</code><i>XXX</i> methods defined in 
 this class. </TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../javax/servlet/http/HttpServlet.html#service(javax.servlet.ServletRequest, javax.servlet.ServletResponse)">service</A></B>(<A HREF="../../../javax/servlet/ServletRequest.html" title="interface in javax.servlet">ServletRequest</A>&nbsp;req,
        <A HREF="../../../javax/servlet/ServletResponse.html" title="interface in javax.servlet">ServletResponse</A>&nbsp;res)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Dispatches client requests to the protected
 <code>service</code> method. </TD>
</TR>
</TABLE>
&nbsp;<A NAME="methods_inherited_from_class_javax.servlet.GenericServlet"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor">
<TD><B>Methods inherited from class javax.servlet.<A HREF="../../../javax/servlet/GenericServlet.html" title="class in javax.servlet">GenericServlet</A></B></TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="../../../javax/servlet/GenericServlet.html#destroy()">destroy</A>, <A HREF="../../../javax/servlet/GenericServlet.html#getInitParameter(java.lang.String)">getInitParameter</A>, <A HREF="../../../javax/servlet/GenericServlet.html#getInitParameterNames()">getInitParameterNames</A>, <A HREF="../../../javax/servlet/GenericServlet.html#getServletConfig()">getServletConfig</A>, <A HREF="../../../javax/servlet/GenericServlet.html#getServletContext()">getServletContext</A>, <A HREF="../../../javax/servlet/GenericServlet.html#getServletInfo()">getServletInfo</A>, <A HREF="../../../javax/servlet/GenericServlet.html#getServletName()">getServletName</A>, <A HREF="../../../javax/servlet/GenericServlet.html#init()">init</A>, <A HREF="../../../javax/servlet/GenericServlet.html#init(javax.servlet.ServletConfig)">init</A>, <A HREF="../../../javax/servlet/GenericServlet.html#log(java.lang.String)">log</A>, <A HREF="../../../javax/servlet/GenericServlet.html#log(java.lang.String, java.lang.Throwable)">log</A></CODE></TD>
</TR>
</TABLE>
&nbsp;<A NAME="methods_inherited_from_class_java.lang.Object"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor">
<TD><B>Methods inherited from class java.lang.<A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A></B></TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#clone()" title="class or interface in java.lang">clone</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#equals(java.lang.Object)" title="class or interface in java.lang">equals</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#finalize()" title="class or interface in java.lang">finalize</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#getClass()" title="class or interface in java.lang">getClass</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#hashCode()" title="class or interface in java.lang">hashCode</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#notify()" title="class or interface in java.lang">notify</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#notifyAll()" title="class or interface in java.lang">notifyAll</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#toString()" title="class or interface in java.lang">toString</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#wait()" title="class or interface in java.lang">wait</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#wait(long)" title="class or interface in java.lang">wait</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#wait(long, int)" title="class or interface in java.lang">wait</A></CODE></TD>
</TR>
</TABLE>
&nbsp;
<P>

<!-- ============ FIELD DETAIL =========== -->


<!-- ========= CONSTRUCTOR DETAIL ======== -->

<A NAME="constructor_detail"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TD COLSPAN=1><FONT SIZE="+2">
<B>Constructor Detail</B></FONT></TD>
</TR>
</TABLE>

<A NAME="HttpServlet()"><!-- --></A><H3>
HttpServlet</H3>
<PRE>
public <B>HttpServlet</B>()</PRE>
<DL>
<DD>Does nothing, because this is an abstract class.
<P>
</DL>

<!-- ============ METHOD DETAIL ========== -->

<A NAME="method_detail"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TD COLSPAN=1><FONT SIZE="+2">
<B>Method Detail</B></FONT></TD>
</TR>
</TABLE>

<A NAME="doGet(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)"><!-- --></A><H3>
doGet</H3>
<PRE>
protected void <B>doGet</B>(<A HREF="../../../javax/servlet/http/HttpServletRequest.html" title="interface in javax.servlet.http">HttpServletRequest</A>&nbsp;req,
                     <A HREF="../../../javax/servlet/http/HttpServletResponse.html" title="interface in javax.servlet.http">HttpServletResponse</A>&nbsp;resp)
              throws <A HREF="../../../javax/servlet/ServletException.html" title="class in javax.servlet">ServletException</A>,
                     <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/io/IOException.html" title="class or interface in java.io">IOException</A></PRE>
<DL>
<DD>Called by the server (via the <code>service</code> method) to
 allow a servlet to handle a GET request. 

 <p>Overriding this method to support a GET request also
 automatically supports an HTTP HEAD request. A HEAD
 request is a GET request that returns no body in the
 response, only the request header fields.

 <p>When overriding this method, read the request data,
 write the response headers, get the response's writer or 
 output stream object, and finally, write the response data.
 It's best to include content type and encoding. When using
 a <code>PrintWriter</code> object to return the response,
 set the content type before accessing the
 <code>PrintWriter</code> object.

 <p>The servlet container must write the headers before
 committing the response, because in HTTP the headers must be sent
 before the response body.

 <p>Where possible, set the Content-Length header (with the
 <A HREF="../../../javax/servlet/ServletResponse.html#setContentLength(int)"><CODE>ServletResponse.setContentLength(int)</CODE></A> method),
 to allow the servlet container to use a persistent connection 
 to return its response to the client, improving performance.
 The content length is automatically set if the entire response fits
 inside the response buffer.

 <p>When using HTTP 1.1 chunked encoding (which means that the response
 has a Transfer-Encoding header), do not set the Content-Length header.

 <p>The GET method should be safe, that is, without
 any side effects for which users are held responsible.
 For example, most form queries have no side effects.
 If a client request is intended to change stored data,
 the request should use some other HTTP method.

 <p>The GET method should also be idempotent, meaning
 that it can be safely repeated. Sometimes making a
 method safe also makes it idempotent. For example, 
 repeating queries is both safe and idempotent, but
 buying a product online or modifying data is neither
 safe nor idempotent. 

 <p>If the request is incorrectly formatted, <code>doGet</code>
 returns an HTTP "Bad Request" message.
<P>
<DD><DL>
</DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>req</CODE> - an <A HREF="../../../javax/servlet/http/HttpServletRequest.html" title="interface in javax.servlet.http"><CODE>HttpServletRequest</CODE></A> object that
			contains the request the client has made
			of the servlet<DD><CODE>resp</CODE> - an <A HREF="../../../javax/servlet/http/HttpServletResponse.html" title="interface in javax.servlet.http"><CODE>HttpServletResponse</CODE></A> object that
			contains the response the servlet sends
			to the client
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.4/docs/api/java/io/IOException.html" title="class or interface in java.io">IOException</A></CODE> - if an input or output error is 
				detected when the servlet handles
				the GET request
<DD><CODE><A HREF="../../../javax/servlet/ServletException.html" title="class in javax.servlet">ServletException</A></CODE> - if the request for the GET
					could not be handled<DT><B>See Also:</B><DD><A HREF="../../../javax/servlet/ServletResponse.html#setContentType(java.lang.String)"><CODE>ServletResponse.setContentType(java.lang.String)</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="getLastModified(javax.servlet.http.HttpServletRequest)"><!-- --></A><H3>
getLastModified</H3>
<PRE>
protected long <B>getLastModified</B>(<A HREF="../../../javax/servlet/http/HttpServletRequest.html" title="interface in javax.servlet.http">HttpServletRequest</A>&nbsp;req)</PRE>
<DL>
<DD>Returns the time the <code>HttpServletRequest</code>
 object was last modified,
 in milliseconds since midnight January 1, 1970 GMT.
 If the time is unknown, this method returns a negative