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Appendix D. JSP API Reference 549 double quotes, slashes, question marks, at signs, colons, and semicolons. Empty values may not behave the same way on all browsers. public void setVersion(int version) Sets the version of the cookie protocol this cookie complies with. A value of 0 means that the cookie must be sent to the browser as described by the original Netscape specification; 1 that the cookie must be sent as defined by RFC 2109. RequestDispatcher The RequestDispatcher class defines an object that receives requests from the client and sends them to any resource (such as a servlet, HTML file, or JSP file) in the same web container. The container creates the RequestDispatcher object, which is used as a wrapper around a resource located at a particular URI path or identified by a particular name. Synopsis Interface name: javax.servlet.RequestDispatcher Extends: None Implemented by: Internal container-dependent class. Methods public void forward(ServletRequest req, ServletResponse res) Forwards a request from a servlet to another resource (servlet, JSP file, or HTML file) on the server. For a RequestDispatcher obtained via getRequestDispatcher( ), the ServletRequest object has its path elements and parameters adjusted to match the path of the target resource. This method must be called before the response has been committed to the client (before response body output has been flushed). If the response has already been committed, this method throws an IllegalStateException. Uncommitted output in the response buffer is automatically cleared before the forward. The request and response parameters must be the same objects as were passed to the calling servlet's service method or be subclasses of the ServletRequestWrapper or ServletResponseWrapper classes that wrap them. public void include(ServletRequest req, ServletResponse res) Includes the response generated by a resource (servlet, JSP page, HTML file) in the response. Appendix D. JSP API Reference 550 The ServletResponse object's path elements and parameters remain unchanged from the caller's. The included servlet can't change the response status code or set headers; any attempt to make a change is ignored. The request and response parameters must be the same objects that were passed to the calling servlet's service method or be subclasses of the ServletRequestWrapper or ServletResponseWrapper classes that wrap them. D.3 Tag Handler Types The JSP specification defines a number of classes and interfaces in the javax.servlet.jsp.tagext package. These classes are used to develop tag handler classes for JSP custom actions. This section contains descriptions of each class and interfaces. Chapter 20 and Chapter 21 show examples of how you can use these classes and interfaces to develop custom actions. BodyContent The container creates an instance of the BodyContent class to encapsulate the element body of a custom action element if the corresponding tag handler implements the BodyTag interface. The container makes the BodyContent instance available to the tag handler by calling the setBodyContent( ) method, so the tag handler can process the body content. Synopsis Class name: javax.servlet.jsp.tagext.BodyContent Extends: javax.servlet.jsp.JspWriter Implements: None Implemented by: Internal container-dependent class. Constructor protected BodyContent(JspWriter e) Creates a new instance with the specified JspWriter as the enclosing writer. Methods public void clearBody( ) Removes all buffered content for this instance. . so the tag handler can process the body content. Synopsis Class name: javax.servlet.jsp.tagext.BodyContent Extends: javax.servlet.jsp.JspWriter Implements: None Implemented by: Internal. located at a particular URI path or identified by a particular name. Synopsis Interface name: javax.servlet.RequestDispatcher Extends: None Implemented by: Internal container-dependent class Forwards a request from a servlet to another resource (servlet, JSP file, or HTML file) on the server. For a RequestDispatcher obtained via getRequestDispatcher( ), the ServletRequest object