Web&java. jsp
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Java Server Pages (JSP) allow you to separate the dynamic parts of your web pages from the static HTML. You write normal HTML code using a web page authoring tool, and then enclose dynamic code sections within special tags that mostly start with "<%" and end with "%>". JSP provides various tags like scriptlets, expressions, comments, and directives to embed Java code within web pages to add dynamic functionality. Common uses of JSP include dynamically generating content, connecting to databases to retrieve and display data, and controlling the page flow based on user input.
![JSP Declarations:
<%! declaration; [ declaration; ]
+ ... %>
<%! int i = 0; %>
<%! int a, b, c; %>
<%! Circle a = new Circle(2.0); %>](https://image.slidesharecdn.com/webjava-150331065812-conversion-gate01/85/Web-java-jsp-8-320.jpg)
Web&java. jsp
- 3. JavaServer Pages (JSP) позволяют вам отделить динамическую часть ваших страниц от статического HTML. Вы, как обычно, пишете обычный код в HTML, используя для этого любую программу для создания Web страниц. Затем вы заключаете динамическую часть кода в специальные таги, большинство которых начинаются с "<%" и завершаются "%>".
- 5. First jsp <html> <head> <title> Hello World Sample </title> </head> <body> <h1> <% String name = request.getParameter("name"); if (name == null || name.length() == 0) { %> Hello, world ! <% } else { %> Hello, world ! I'm <%= name%> <% } %> </h1> </body> </html>
- 6. Структура каталога web-app в каталоге src.
- 7. Синтаксис jsp. The Scriptlet:<% code fragment %> <html> <head> <title>Hello World</title></head> <body> Hello World!<br/> <% out.println("Your IP address is " + request.getRemoteAddr()); %> </body> </html>
- 8. JSP Declarations: <%! declaration; [ declaration; ] + ... %> <%! int i = 0; %> <%! int a, b, c; %> <%! Circle a = new Circle(2.0); %>
- 9. JSP Expression: <%= expression %> <html> <head> <title>A Comment Test</title></head> <body> <p> Today's date: <%= (new java.util.Date()).toLocaleString()%> </p> </body> </html> Today's date: 21-Sep-2015 21:24:25
- 10. JSP Comments: <%-- This is JSP comment --%> <html> <head> <title>A Comment test</title></head> <body> <h2>A Test of Comments</h2> <%-- This comment will not be visible in the page source --%> </body> </html>
- 11. JSP Directives: <%@ directive attribute="value" %> <%@ page ... %>Defines page- dependent attributes, such as scripting language, error page, and buffering requirements. <%@ include ... %>Includes a file during the translation phase. <%@ taglib ... %>Declares a tag library, containing custom actions, used in the page
- 12. JSP Actions: <jsp:action_name attribute="value" /> jsp:include Includes a file at the time the page is requested jsp:useBean Finds or instantiates a JavaBean jsp:setProperty Sets the property of a JavaBean jsp:getProperty Inserts the property of a JavaBean into the output jsp:forward Forwards the requester to a new page jsp:plugin Generates browser-specific code that makes an OBJECT or EMBED tag for the Java plugin jsp:element Defines XML elements dynamically. jsp:attribute Defines dynamically defined XML element's attribute. jsp:body Defines dynamically defined XML element's body. jsp:text Use to write template text in JSP pages and documents.
- 13. JSP Implicit Objects: request This is the HttpServletRequest object associated with the request. response This is the HttpServletResponse object associated with the response to the client. out This is the PrintWriter object used to send output to the client. session This is the HttpSession object associated with the request. application This is the ServletContext object associated with application context. config This is the ServletConfig object associated with the page. pageContext This encapsulates use of server-specific features like higher performance JspWriters. page This is simply a synonym for this, and is used to call the methods defined by the translated servlet class. Exception The Exception object allows the exception data to be accessed by designated JSP.
- 14. Простой проект с xml-базой данных и jsp
- 21. Result