Custom Framework (mymvc)

Initial contact with the custom framework, simple login function Implementation process::

When we implement the login function, we will first create a login.jsp

Will write these login forms

  <form action= "loginaction.action" method= "post" >     name:<input type= "text" name= "name"/>< br/>     password:<input type= "text" name= "pwd"/><br/>    <input type= "submit" value= "login" >    </form>

of course, all we need to do right now is to write our own framework for successful deployment when the project starts

First we have to let the program start a servlet on its own and write its own Framework's process deployment in the Servlet.

Need to be configured in Web. XML

<!--a value of 0 or greater than 0 o'clock indicates that the container loads the servlet when the app is started;
<load-on-startup>0</load-on-startup>

<?xml version= "1.0" encoding= "UTF-8"?><!--define The constraint file--><!--element represents the elements--><!--attlist represents the property-->& lt;! --CDATA represents a string Type--><!--REQUIRED indicates that this property must be write--><!--* represents multiple--><!--implied indicates that this property can be written--><!DOCTYPE framework[<! ELEMENT Framework (actions) > <! ELEMENT Actions (action*) > <! ELEMENT Action (result*) > <!attlist action name CDATA #REQUIREDclassCDATA #REQUIRED> <!attlist RESULT name CDATA #IMPLIED Redirect (true|false) "false" >]><Framework><actions> <action name= "loginaction"class= "action.loginaction" > <result name= "success" >success.jsp</result> <result name= "login" > Index.jsp</result> </action></actions></Framework>

 public voidInit (servletconfig Config)throwsservletexception {//the Config object is an object of javax.servlet.ServletConfig, and the function is to obtain initialization configuration information//Config.getinitparameter is the content of the initialization parameter that obtains the specified nameString filename = Config.getinitparameter ("config"); System.out.println ("gg\t" +filename); String [] Filenames=NULL; if(filename==NULL)        {            //If there is no other parameter information, put it in an array that is already well-equippedfilenames=Newstring[]{"framework.xml"};  for(string string:filenames) {System.out.println (string); }        }        Else        {            //If there are additional configuration parameter information, then separate into the arrayFilenames=filename.split (",");  for(string string:filenames) {System.out.println (string+ "\ t"); }        }        //initializing using the Init method       man=new Actionmappingmanager (filenames); }

Because the code is red, he will execute the following code:

 packageAction;/*** Step three: * Because there are more than one action node, you need to configure a Actionmappingmanage class to manage the Actionmapping class*/Importjava.io.InputStream;Importjava.util.HashMap;Importjava.util.Iterator;Importjava.util.Map;Importorg.dom4j.Document;Importorg.dom4j.Element;Importorg.dom4j.io.SAXReader;/*** Because this class is an action * It contains a member variable that is customized to key value in the form of a name value, each of the actions in the?? each name represents a key * each action represents a A value *@authorSLEEP * Parse the node object in the resource file **/ public classActionmappingmanager {//collection of actionmapping classes  PrivateMap<string,actionmapping> maps=NewHashmap<string,actionmapping>();  publicactionmapping getactionmapping (String Name) {returnMaps.get (name); }  //get actions from an XML file that is assembled by Init   publicActionmappingmanager (string[] files) { for(String filename:files) {Init (filename); }  }  //Create an initialization method, use DOM4J to parse the configuration file   public voidInit (String Path) {System.out.println ("oh-----------------------------------------"); Try {         //getResourceAsStream Gets the reference to the resource input stream to ensure that the program can extract data from the correct location//Convert the Framework.xml resource object into a streamInputStream is= this. getclass (). getResourceAsStream ("/" +path); //parsing XML using the Saxreader object to read the streamDocument doc=NewSaxreader (). Read (is); //Get root nodeElement root =doc.getrootelement (); //get the first acitons node in a custom frameElement actions=( Element) root.elementiterator (). Next (); System.out.println ("root node" +Actions.getname ()); //use a For loop to traverse all action nodes under the Actions node           for(iterator<element> action=actions.elementiterator (); Action.hasnext ();) {              //get to <action> node action is a collection of actions, we want to take out the first itemElement Actionnext =Action.next (); System.out.println ("child nodes under root node" +Actionnext.getname ()); //get the Name property and class property in the action node, respectivelyString name = Actionnext.attributevalue ("name"); String ClassName= Actionnext.attributevalue ("class"); //Save the above two attributes to the Actionmapping classActionmapping mapp=Newactionmapping ();              Mapp.setclassname (classname);              Mapp.setname (name); //because there are multiple result nodes under an action node that traverse all the result nodes under Action               for(iterator<element> Result=actionnext.elementiterator ("result"); Result.hasnext ();) {                  //get to the result nodeElement Resultnext =Result.next (); //extracts the Name property value of the result node and the value in the result nodeString resultname = Resultnext.attributevalue ("name"); String Resultvalue=Resultnext.gettext (); //It is easy to call the Actionmapping class (there is data in the actionmapping Class) by depositing it into a Double-column collection in Actionmapping .Mapp.addresult (resultname, resultvalue);              System.out.println (mapp.getname ()); }              //get a collection of all action nodesmaps.put (mapp.getname (), mapp); }              } Catch(Exception E) {e.printstacktrace (); }        }}

After init execution in the Servlet method is complete, our Tomcat successfully opens

When we click Log in because it is a post request, the Dopost method in the servlet is automatically called as Follows:

Actionmappingmanager man=NULL;  public voiddoPost (httpservletrequest request, httpservletresponse response)throwsservletexception, IOException {//because index.jsp is the default request interface, the GetName method obtains the index.jsp corresponding to the key of the map in Actionmappingmanager//get to Actionmapping objectActionmapping actionmapping =man.getactionmapping (getname (request)); //get the action interface using the reflection mechanismAction action =Actionmanager.getactionclass (actionmapping.getclassname ()); Try {            //returns a logical view nameString message =Action.execute (request, response); String Results=Actionmapping.getresults (message);        Response.sendredirect (results); } Catch(Exception E) {//TODO auto-generated Catch blockE.printstacktrace (); }    }    //get the requested path name Example: day01_0100/index.jsp gets the index.jsp     publicString getname (httpservletrequest request) {//Item + Request addressString RequestUri =Request.getrequesturi ();        System.out.println (requesturi); //Project NameString ContextPath =Request.getcontextpath ();        System.out.println (contextpath); //a specific requestString path=requesturi.substring (contextpath.length ());        System.out.println (path); String filename=path.substring (1,path.lastindexof (".") . Trim ();        System.out.println (filename); returnfilename; }actionmappingmanager Mans=NULL;  public voiddoPost (httpservletrequest request, httpservletresponse response)throwsservletexception, IOException {//because index.jsp is the default request interface, the GetName method obtains the index.jsp corresponding to the key of the map in Actionmappingmanager//get to Actionmapping objectActionmapping actionmapping =man.getactionmapping (getname (request)); //get the action interface using the reflection mechanismAction action =Actionmanager.getactionclass (actionmapping.getclassname ()); Try {            //returns a logical view nameString message =Action.execute (request, response); String Results=Actionmapping.getresults (message);        Response.sendredirect (results); } Catch(Exception E) {//TODO auto-generated Catch blockE.printstacktrace (); }    }    //get the requested path name Example: day01_0100/index.jsp gets the index.jsp     publicString getname (httpservletrequest request) {//Item + Request addressString RequestUri =Request.getrequesturi ();        System.out.println (requesturi); //Project NameString ContextPath =Request.getcontextpath ();        System.out.println (contextpath); //a specific requestString path=requesturi.substring (contextpath.length ());        System.out.println (path); String filename=path.substring (1,path.lastindexof (".") . Trim ();        System.out.println (filename); returnfilename; }

Since custom MVC does not have interceptors, <url-pattern>*.action</url-pattern>

<servlet-mapping>
<servlet-name>myServlet</servlet-name>
<!--there is no filter like struts2, manually restricting all action---
<url-pattern>*.action</url-pattern>
</servlet-mapping>

Such a custom framework is done!

Custom Framework (mymvc)