JSP built-in object -- Exception

The exception object is an instance of throwable, which represents errors and exceptions generated in JSP scripts and is part of the JSP page exception mechanism. You do not need to handle exceptions in JSP scripts, even checked exceptions. In fact, all possible exceptions contained in JSP can be handled on the error handling page.

Open the servlet class generated on the common JSP page and you will find the following code snippets.

Try {

} Catch (throwable t ){

If (_ jspx_page_context! = NULL) // this judgment is determined by the page compilation command page (errorpage)

}

Note: When the iserrorpage of the JSP page command is true, the page provides the built-in exception object.