Java Web project gets various paths

1. You can do this in the Init method of the servlet

String path = Getservletcontext (). Getrealpath ("/"); This gets the full path of the Web project for example: E:\eclipseM9\workspace\tree\ Tree is the root of my Web Project 2. You can also call This.getclass () in any class at any time. getClassLoader (). GetResource ("/"). GetPath (); this will get Full path to classes directory for example: E:\eclipsem9/workspace/tree/web-inf/classes/This method can also be used in the WEB environment to determine the path, more useful 3.request.getcontextpath ( ); Get the Web root context environment such as/tree Www.2cto.comtree is the root of my Web project context/*jsp get the path Path=request.getrealpath ("") of the current directory;/* Get Jbossweb Release Temp directory warurl=.../tmp/deploy/tmp14544test-exp.war/path=c:\jboss-4.0.5.ga\server\default\tmp\deploy\ tmp14544test-exp.war\string path = (String) request.getcontextpath ();/* Gets the real path to the project (test) application path=/teststring Path = Request.getrequesturi ();/* Get the actual path where the application resides path=/test/admin/admindex.jspstring Savepath=request.getrealpath ( Request.getservletpath ());/* Gets the disk absolute path of the current file//java gets the path to the current directory, file File=new file ("."); String Path=file.getabsolutepath ();p ath=file.getpath ();/* Get JBoss Run directory path=c:\jboss-4.0.5.ga\bin\---------------- -----------------------------Java relative path/absolute path summary 1. The basic concept of Understanding absolute path: absolute path is yourThe real path to the file or directory on the hard disk on the home page (URL and physical path) For example: C:xyz est.txt represents the absolute path to the Test.txt file. The http://www.sun.com/index.htm also represents a URL absolute path. Relative path: The path relative to a base directory. Contains the relative path to the web (relative to the directory in HTML), for example: In a servlet, "/" represents a directory of Web apps. and the relative representation of the physical path. For example: "./" represents the current directory, ". /"represents the parent directory. This similar representation also belongs to the relative path. For additional information about Uri,url,urn, please refer to RFC documentation standards. RFC 2396:uniform Resource Identifiers (URI): Generic Syntax, (http://www.ietf.org/rfc/rfc2396.txt)  2. About jsp/ The relative path and absolute path in the servlet. 2.1 Server-side address server-side relative address refers to the address of your Web application, which is resolved on the server side (different from HTML and JavaScript relative address, They are parsed by the client browser) in other words, the relative addresses in the JSP and servlet should be relative to your Web application, which is relative to http://192.168.0.1/webapp/. Where it is used: request.getrequestdispatcher (address) in Forward:servlet; This address is parsed on the server side, so You want to forward to a.jsp should write: Request.getrequestdispatcher ("/user/a.jsp") this/relative to the current Web application WebApp, its absolute address is:/http 192.168.0.1/webapp/user/a.jsp. Sendredirect: <%response.sendredirect ("/rtccp/user/a.jsp") in the JSP; the relative addresses in all HTML pages of the%>2.22 and client addresses are relative to the server root directory ( HTTP://192.168.0.1/), instead of (with the directory of the Web app under the directory) http://192.168.0.1/webapp/. The address of the Action property of the form form in HTML should be relative to the server root directory (http://192.168.0.1/), so if submitted to a.jsp for: action= "/webapp/user/a.jsp" or action= "<%=request.getcontextpath ()% >"/user/ a.jsp; submitted to the servlet as actiom= "/webapp/handleservlet" JavaScript is also parsed on the client, so its relative path is the same as the form form.   Therefore, in general, in the Jsp/html page and other references such as css,javascript.action and other properties are preferably preceded by <%=request.getcontextpath ()%> To ensure that the referenced files belong to a directory in your Web app. In addition, you should try to avoid the use of similar ".", "./", ". /.. /"Similar relative path relative to the location of the file, so that when the file is moved, it is prone to problems.  3. Obtain the current applied relative path and absolute path in the Jsp/servlet 3.1 jsp to get the absolute path for the current app's relative path and absolute path root: Request.getrequesturi () file: Application.getrealpath (Request.getrequesturi ()); absolute path to the current Web application: Application.getrealpath ("/"); Gets the upper-level directory of the requested file: New file (Application.getrealpath (Request.getrequesturi ())). GetParent () 3.2 servlet gets the absolute path corresponding to the current app's relative path and absolute path root: Request.getservletpath (); absolute path to file: Request.getsession (). Getservletcontext (). Getrealpath (Request.getrequesturi ()) Absolute path for the current web app: Servletconfig.getservletcontext (). Getrealpath ("/");( ServletContext objects are available in several ways: Javax.servlet.http.HttpSession.getServletContext () Javax.servlet.jsp.PageContext.getServletContext () javax.seRvlet. Servletconfig.getservletcontext ()) 4.java gets the relative path in class, absolute path method 4.1 In separate Java class obtains absolute path according to Java.io.File doc block, know: By default, the directory represented by new File ("/") is: System.getproperty ("User.dir"). The program obtains the current path of the execution class package Org.cheng.file; import Java.io.file; public class filetest ... {public static void main (string[] args) throws Exception ... {System.out.println (Thread.CurrentThread (). Getcontextclassloader (). GetResource (""));  system.out.println ( FileTest.class.getClassLoader (). GetResource (""));  system.out.println (Classloader.getsystemresource ("")); System.out.println (FileTest.class.getResource ("")); System.out.println (FileTest.class.getResource ("/"));//class file is located in the path System.out.println (new file ("/"). GetAbsolutePath ()); System.out.println (System.getproperty ("User.dir"));}} 4.2 The Java class in the server obtains the current path (1). The weblogicwebapplication system file root directory is the root directory where your WebLogic installation is located. For example: If your WebLogic is installed in c:beaweblogic700 ..... So, your file root path is C:. So there are two ways you can access your server-side files: A. Use absolute path: For example, put your parameter file in C:yourconfigyourconf.properties, use new directly FileInputStream ("Yourconfig/yoUrconf.properties "); B. Using a relative path: the root of the relative path is the root of your webapplication, which is the top-level directory of Web-inf, where you put your parameter file in Yourwebappyourconfigyourconf.properties, so you use: New FileInputStream ("./yourconfig/yourconf.properties"), both of which can be chosen by themselves. (2). Tomcat outputs System.getproperty ("User.dir") in the class, and%tomcat_home%/bin (3) is displayed. Resin is not the relative path that your JSP puts, it is the JSP engine that executes this JSP to compile the path of the servlet to the root. For example, use the new file method to test file F = new ("A.htm"), which is a.htm in the Resin installation directory (4). How to read a relative path? Examples of getresource or getResourceAsStream in Java files are: GetClass (). getResourceAsStream (FilePath);//filepath can be "/filename", Here/on behalf of the WEB publishing root path under Web-inf/classes The default path for using this method is: web-inf/classes. has been tested in Tomcat. Summary: Through the use of the above content can be resolved in the Web application server side, move files, find files, copy delete files and other operations, while the relative address of the server, the absolute address concept clearer. Recommended reference URI, RFC standard text block. At the same time, the understanding of Java.io.File Java.net.URI and other aspects can be more thorough and thorough. This is the way to go to the root directory of the current project in Java Java code/** *//*** TODO Get the root of the current project * @author Pheh*/public class application ... { /** *//*** TODO get root directory * @return * @author pheh*/public static String Getrootpath () ... {//Because the class name is "Application", "Application.class" must be able to find string result = Application.class.getResource ("ApplicatIon.class "). toString (); int index = Result.indexof (" Web-inf "); if (index = =-1) ... {index = Result.indexof ("bin");} result = Result.substring (0,index), if (Result.startswith ("jar")) ... {//When the class file is in the jar file, the path of "jar:file:/f:/..." is returned as result = Result.substring (10);} else if (result.startswith ("file")) ... {//When the class file is in the class file, return the path of "file:/f:/..." to result = result.substring (6);} if (Result.endswith ("/")) result = Result.substring (0,result.length ()-1);//does not contain the final "/" return result;}

Java Web project gets various paths