Programming Articles - Page 2812 of 3366

The contentType attribute sets the character encoding for the JSP page and for the generated response page. The default content type is text/html, which is the standard content type for HTML pages.If you want to write out XML from your JSP, use the following page directive −The following statement directs the browser to render the generated page as HTML −The following directive sets the content type as a Microsoft Word document −You can also specify the character encoding for the response. For example, if you wanted to specify that the resulting page that is returned to the browser uses ISO ... Read More

The autoFlush attribute specifies whether the buffered output should be flushed automatically when the buffer is filled, or whether an exception should be raised to indicate the buffer overflow.A value of true (default) indicates automatic buffer flushing and a value of false throws an exception.The following directive causes the servlet to throw an exception when the servlet's output buffer is full −This directive causes the servlet to flush the output buffer when full −Usually, the buffer and the autoFlush attributes are coded on a single page directive as follows −

The buffer attribute specifies the buffering characteristics for the server output response object.You may code value of "none" to specify no buffering so that the servlet output is immediately directed to the response object or you may code a maximum buffer size in kilobytes, which directs the servlet to write to the buffer before writing to the response object.To direct the servlet to write the output directly to the response output object, use the following −

If you want to handle errors within the same page and want to take some action instead of firing an error page, you can make use of the try....catch block.Following is a simple example which shows how to use the try...catch block. Let us put the following code in main.jsp −           Try...Catch Example                   Access the main.jsp, it should generate an output somewhat like the following −An exception occurred: / by zero

The buffer attribute specifies the buffering characteristics for the server output response object.You may code a value of "none" to specify no buffering so that the servlet output is immediately directed to the response object or you may code a maximum buffer size in kilobytes, which directs the servlet to write to the buffer before writing to the response object.To direct the servlet to write the output directly to the response output object, use the following −Use the following to direct the servlet to write the output to a buffer of size not less than 8 kilobytes −

Following table lists out the attributes associated with the page directive −S.No.Attribute & Purpose1bufferSpecifies a buffering model for the output stream.2autoFlushControls the behavior of the servlet output buffer.3contentTypeDefines the character encoding scheme.4errorPageDefines the URL of another JSP that reports on Java unchecked runtime exceptions.5isErrorPageIndicates if this JSP page is a URL specified by another JSP page's errorPage attribute.6extendsSpecifies a superclass that the generated servlet must extend.7importSpecifies a list of packages or classes for use in the JSP as the Java import statement does for Java classes.8infoDefines a string that can be accessed with the servlet's getServletInfo() method.9isThreadSafeDefines the threading model ... Read More

The page directive is used to provide instructions to the container. These instructions pertain to the current JSP page. You may code page directives anywhere in your JSP page. By convention, page directives are coded at the top of the JSP page.Following is the basic syntax of the page directive −You can write the XML equivalent of the above syntax as follows −AttributesFollowing table lists out the attributes associated with the page directive −S.No.Attribute & Purpose1bufferSpecifies a buffering model for the output stream.2autoFlushControls the behavior of the servlet output buffer.3contentTypeDefines the character encoding scheme.4errorPageDefines the URL of another JSP that ... Read More

You can make use of JSTL tags to write an error page ShowError.jsp with better structure and more information −           Show Error Page               Opps...                             Error:             ${pageContext.exception}                                 URI:             ${pageContext.errorData.requestURI}                             ... Read More

JSP gives you an option to specify Error Page for each JSP using page attribute. Whenever the page throws an exception, the JSP container automatically invokes the error page.Following is an example to specifiy an error page for a main.jsp. To set up an error page, use the directive.           Error Handling Example               We will now write one Error Handling JSP ShowError.jsp, which is given below. Notice that the error-handling page includes the directive . This directive causes the JSP compiler ... Read More

The exception object is a wrapper containing the exception thrown from the previous page. It is typically used to generate an appropriate response to the error condition.When you are writing a JSP code, you might make coding errors which can occur at any part of the code. There may occur the following type of errors in your JSP code −Checked exceptionsA checked exception is an exception that is typically a user error or a problem that cannot be foreseen by the programmer. For example, if a file is to be opened, but the file cannot be found, an exception occurs. ... Read More