Spring MVC processing Method return mode

Model:

 PackageOrg.springframework.ui;Importjava.util.Collection;ImportJava.util.Map; Public InterfaceModel {model AddAttribute (String attributename, Object AttributeValue);    Model AddAttribute (Object attributevalue); Model addallattributes (Collection<?>attributevalues); Model addallattributes (Map<string,?>attributes); Model mergeattributes (Map<string,?>attributes); BooleanContainsattribute (String attributename); Map<string, object>Asmap ();}

MAP:

 PackageJava.util; Public InterfaceMap<k,v> {    intsize (); BooleanIsEmpty (); BooleanContainsKey (Object key); BooleanContainsvalue (Object value);    V get (Object key);    V Put (K key, v value);    V Remove (Object key); voidPutall (map<?extendsK?extendsV>m); voidClear (); Set<K>KeySet (); Collection<V>values (); Set<map.entry<k, v>>EntrySet (); InterfaceEntry<k,v>{K getKey ();        V GetValue ();        V SetValue (v value); Booleanequals (Object O); inthashcode (); }    //Comparison and hashing    Booleanequals (Object O); inthashcode ();}

Modelmap:

 PackageOrg.springframework.ui;Importjava.util.Collection;ImportJava.util.LinkedHashMap;ImportJava.util.Map;Importorg.springframework.core.Conventions;ImportOrg.springframework.util.Assert; @SuppressWarnings ("Serial") Public classModelmapextendsLinkedhashmap<string, object> {     PublicModelmap () {} PublicModelmap (String attributename, Object attributevalue) {AddAttribute (AttributeName, AttributeValue); }     PublicModelmap (Object attributevalue) {AddAttribute (AttributeValue); }     Publicmodelmap AddAttribute (String attributename, Object attributevalue) {assert.notnull (AttributeName,"Model attribute name must not being null");        Put (AttributeName, AttributeValue); return  This; }     Publicmodelmap AddAttribute (Object attributevalue) {assert.notnull (AttributeValue,"Model object must not being null"); if(AttributeValueinstanceofCollection && (collection<?>) AttributeValue). IsEmpty ()) {return  This; }        returnAddAttribute (Conventions.getvariablename (AttributeValue), AttributeValue); }     PublicModelmap Addallattributes (collection<?>attributevalues) {        if(Attributevalues! =NULL) {             for(Object attributevalue:attributevalues) {AddAttribute (AttributeValue); }        }        return  This; }     PublicModelmap addallattributes (map<string,?>attributes) {        if(Attributes! =NULL) {putall (attributes); }        return  This; }     PublicModelmap mergeattributes (map<string,?>attributes) {        if(Attributes! =NULL) {             for(Map.entry<string,?>Entry:attributes.entrySet ()) {String key=Entry.getkey (); if(!ContainsKey (Key))                {Put (key, Entry.getvalue ()); }            }        }        return  This; }     Public BooleanContainsattribute (String attributename) {returnContainsKey (AttributeName); }}

View:

 PackageOrg.springframework.web.servlet;ImportJava.util.Map;Importjavax.servlet.http.HttpServletRequest;ImportJavax.servlet.http.HttpServletResponse;ImportOrg.springframework.http.MediaType; Public InterfaceView {String Response_status_attribute= View.class. GetName () + ". ResponseStatus"; String Path_variables= View.class. GetName () + ". Pathvariables"; String Selected_content_type= View.class. GetName () + ". Selectedcontenttype";    String getContentType (); voidRender (map<string,?> model, httpservletrequest request, httpservletresponse response)throwsException;}

Modelandview:

 PackageOrg.springframework.web.servlet;ImportJava.util.Map;ImportOrg.springframework.ui.ModelMap;Importorg.springframework.util.CollectionUtils; Public classModelandview {PrivateObject View; PrivateModelmap model; Private Booleancleared =false;  PublicModelandview () {} PublicModelandview (String viewName) { This. View =ViewName; }     PublicModelandview (view view) { This. View =view; }     PublicModelandview (String viewName, map<string,?>model) {         This. View =ViewName; if(Model! =NULL) {Getmodelmap (). Addallattributes (model); }    }     PublicModelandview (view view, map<string,?>model) {         This. View =view; if(Model! =NULL) {Getmodelmap (). Addallattributes (model); }    }     PublicModelandview (String viewName, String modelname, Object modelobject) { This. View =ViewName;    AddObject (ModelName, modelobject); }     PublicModelandview (view view, String modelname, Object modelobject) { This. View =view;    AddObject (ModelName, modelobject); }     Public voidsetviewname (String viewName) { This. View =ViewName; }     PublicString Getviewname () {return( This. ViewinstanceofString? (String) This. View:NULL); }     Public voidSetview (view view) { This. View =view; }     PublicView GetView () {return( This. ViewinstanceofView? (View) This. View:NULL); }     Public BooleanHasview () {return( This. View! =NULL); }     Public Booleanisreference () {return( This. ViewinstanceofString); }    protectedMap<string, object>getmodelinternal () {return  This. Model; }     PublicModelmap Getmodelmap () {if( This. Model = =NULL) {             This. Model =NewModelmap (); }        return  This. Model; }     PublicMap<string, object>Getmodel () {returnGetmodelmap (); }     PublicModelandview AddObject (String attributename, Object attributevalue) {Getmodelmap (). AddAttribute (AttributeName        , AttributeValue); return  This; }     PublicModelandview AddObject (Object attributevalue) {Getmodelmap (). AddAttribute (AttributeValue); return  This; }     PublicModelandview addallobjects (map<string,?>Modelmap)        {Getmodelmap (). Addallattributes (Modelmap); return  This; }     Public voidClear () { This. View =NULL;  This. Model =NULL;  This. cleared =true; }     Public BooleanIsEmpty () {return( This. View = =NULL&& Collectionutils.isempty ( This. Model)); }     Public Booleanwascleared () {return( This. Cleared &&isEmpty ()); } @Override PublicString toString () {StringBuilder sb=NewStringBuilder ("Modelandview:"); if(IsReference ()) {Sb.append ("Reference to view with Name"). Append ( This. View). Append ("'"); }        Else{sb.append ("Materialized View is ["). Append ( This. View). Append ('] '); } sb.append ("; Model is "). Append ( This. Model); returnsb.tostring (); }}

String:

void

Spring MVC processing Method return mode