Currently encountered in the Web project to write URLs and path files have
- In WebContent. jsp/.html
- servlet classes in SRC
- SRC generic class for non-servlet classes
. jsp/.html
Action for Form form submission
1. Jump to. jsp
Use relative paths relative to the Web engineering root directory
<!-- from jsp1.jsp to jsp2.jsp Span style= "COLOR: #008000" >--> <!-- jsp1.jsp in the form --> < form action = "file/jsp2.jsp" >
<!---<!---<Action =".. /jsp1.jsp ">
2. Jump to Servlet1
Not relevant to the package
// Servlet1.java Map Address @WebServlet (name = "Servlet1", Urlpatterns = {"/servlet1"})
<!---<!---<Action =".. /servlet1 ">
Change the map address of the servlet so that the servlet maps to a folder with jsp2.jsp
// @WebServlet After modifying the map address of the Servlet1 (name = "Servlet1", Urlpatterns = {"/file/servlet1"})
<!---<!---<Action = "Servlet1">
Change the servlet mapping address again, the servlet maps to the virtual directory
// after modifying the mapping address of the SERVLET1 again, map to the Virtualfile virtual directory @WebServlet (name = "Servlet1", Urlpatterns = {"/virtualfile/ Servlet1 "})
<!---<!---<Action =".. /virtualfile/servlet1 ">
servlet classes in SRC
1. Map address in URL annotations, contact with JSP (HTML)
2. Access resource files in WebContent 1.txt (according to the engineering structure in Tomcat)
// use Getservletcontext (). Getrealpath () to get the absolute path to the Web project this. Getservletcontext (). Getrealpath ("/sourcefile/1.txt"); // filepath= // D:\tomcat\apache-tomcat-8.0.50-windows-x64\apache-tomcat-8.0.50\webapps\test3\sourceFile\1.txt New BufferedReader (new FileReader (FilePath));
2. Access the resource file in SRC
// access the files in src to get the absolute path according to the project directory in Tomcat // servlet does not map to virtual directory this. Getservletcontext (). Getrealpath ("/web-inf/classes/2.txt"new bufferedwriter ( New FileWriter (FilePath));
3. Redirect to Servlet (JSP), only with relative path
// REDIRECT uses relative path, URL changes response.sendredirect ("file/jsp2.jsp");
4, request forward to servlet (servlet), you can use relative path, absolute path
// relative Path RequestDispatcher rd = Request.getrequestdispatcher ("Servlet2"); Rd.forward (request,response); // Absolute Path RequestDispatcher rd = Request.getrequestdispatcher ("/servlet2"); Rd.forward (request,response);
SRC generic class for non-servlet classes
1. General class access to resource files in WebContent
// use class to get the directory where this class is located (without Pacakage, only to classes), // get the absolute path of the resource file using GetResource () // in WebContent two times to return to the parent directory (Web-inf, project name Urltest) New File (Normalclass. Class. getClassLoader (). GetResource (".. /.. /sourcefile/1.txt "new FileInputStream (FilePath);
2. General class interview resource file in src
// use class to get the directory where this class is located (without Pacakage, only to classes), // get the absolute path of the resource file using GetResource () New File (Normalclass. Class. getClassLoader (). GetResource ("2.txt"new FileInputStream (FilePath);
Various paths in Web engineering (Eclipse development)