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1. [SAStruts] Show Error Page When Page Does Not Exist

   When a page does not exist, the error message of Apache is displayed

   There is an easy method of making this change to original page in SAStruts

   It is realizable by adding the following description /webapp/WEB-INF/web.xml

   The place to add is over <jsp-config>.

   <error-page>
     <error-code>404</error-code>
     <location>/WEB-INF/view/error/index.jsp</location>
   </error-page>
   

   <error-code> : writes HTTP Status

   <location> : writes jsp url of original page

2. [SAStruts] Create Action Method

   Add annotation Execute to a method in Action Class

   @Execute(validator = false)
   public String index() {
     return "index.jsp";
   }
   

3. [SAStruts] Action, Action Method and URL

   a. SAStruts default

   SAStruts depend on name of Action Class to map with URL, and Action Method in Action Class should be map with sub level.

   E.g. class ExampleAction include Action Method named methodName, then URL are http://domain/context/example and http://domain/context/example/methodName

   b. Customize action method URL

   Specified urlPattern in annotation Execute

   @Execute(validator = false, urlPattern = "urlName")
   public String methodName() {
     return "index.jsp";
   }
   

   Now, URL change to http://domain/context/example/urlName

   c. Pass parameters in URL for Action Method

   Action Method parsing parameter from URL with urlPattern

   @Execute(validator = false, urlPattern = "urlName/{year}/{month}/{day}")
   public String methodName() {
     return "index.jsp";
   }
   

   year, month, day pass to method, to get their values, parameters must be declare in Action Form

   d. Warning, using urlPattern same pattern for many Action Method easy to cause confusion, sometime exception occur

   @Execute(validator = false, urlPattern = "{year}/{month}/{day}")
   public String oneMethod() {
     return "index.jsp";
   }
   @Execute(validator = false, urlPattern = "twoMethod/{month}/{day}" )
   public  String twoMethod() {
     return "index.jsp";
   }
   

4. [SAStruts] Return View when Action Method finished

   a. Return jsp

   public class FooAction {
     @Execute(validator = false)
     public String foo() {
       return "index.jsp";
     }
   }
   

   SAStruts implicit return src/main/webapp/WEB-INF/view/foo/index.jsp

   b. Return Action (redirect) - REST

   public class FooAction {
     @Execute(validator = false)
     public String foo() {
       return "/baz/plus?redirect=true";
     }
   }
   

   c. Return Action (redirect) with parameters

   public class FooAction {
     @Execute(validator = false)
     public String foo() {
       return "/baz/plus?age=25&redirect=true";
     }
   }
   

   d. Clear Form object stored in Session Scope when Action finished normally (until JSP complete)

   Flow: Edit screen => do Save (error) => Edit screen, refill value almost using Session Scope.

   If Save success (no error), the temporary values become unnecessary, should be remove.

   In annotation Execute, we can specify option removeActionForm = true, it mean framwork should be remove values in ActionForm when Action finished normally.

   public class FooAction {
     @Execute(validator = false, removeActionForm = true)
     public String foo() {
       return "/baz/plus?age=25&redirect=true";
     }
   }
   

5. [SAStruts] Validate input data

   a. Validate with Form

   i. What's Form: See How to Use SAStruts Form

   ii. Validate

   Add option validator in Execute annotation is true, validate input rules may be code in Form. Further, we can specify error page when validation occur.

   public class FooAction {
     @Execute(validator = true, input = "error.jsp")
     public String foo() {
       return "index.jsp";
     }
   }
   

   b. Validate data by Action Method

   i. Specify validate method

   Specify validate method name by option validate in Execute annotation

   public class FooAction {
     @Execute(validator = true, validate = "fooValidator", input = "error.jsp")
     public String foo() {
       return "index.jsp";
     }
   }
   

   Only one method accepted.

   ii. Write validate method

   Validate method place in Action class use this validate.

   To validate input for method foo, create fooValidator.

   public ActionMessages fooValidator() {
     ActionMessages errors = new ActionMessages();
     if (!"2013".equals(fooForm.year)) {
       errors.add("no2013", new ActionMessage("foo.index.error.no2013"));
     }
     return errors;
   }
   

   Return ActionMessages data type, if errors has value then go to error page.

   Error message got by key (e.g. no2013) from application.properties to create ActionMessage, and then added to errors.

   c. Validate both validate method and Form class

   At first, input validated by Form, and then validate method executed.

   Default, if input validate by Form got errors, then validate method not execute.

   When option stopOnValidationError is false in Execute annotation, if validate by Form got error, validate method still executed.

   public class FooAction {
     @Execute(validator = true, validate = "fooValidator", input = "error.jsp", stopOnValidationError = false)
     public String foo() {
       return "index.jsp";
     }
   }
   

   d. Specify error page or action when exception occur

   Use option input of Execute annotation to specify destination when exception occur.

   public class FooAction {
     @Execute(validator = true, validate = "fooValidator", input = "error.jsp")
     public String foo() {
       return "index.jsp";
     }
   }
   

   Similar with return page of Action Method

   public class FooAction {
     @Execute(validator = true, validate = "fooValidator", input = "baz/{year}/{month}/{day}?redirect=true")
     public String foo() {
       return "index.jsp";
     }
   }
   

   Flow: Edit screen => do Save (error) => Edit screen

   e. Put error message when exception occur into Session

   Because error message default put in request scope. So when redirect, error message has lost value. If we show error message at destination after redirect, we need put error message in Session Scope.

   Use option saveErrors in Execute annotation, we can specify scope to put error message.

   public class FooAction {
     @Execute(validator = false, saveErrors = SaveType.SESSION)
     public String foo(){
       return "/baz/plus?age=25&redirect=true";
     }
   }
   

   Flow: Edit screen => do Save (error) => Edit screen

6. [JdbcManager] Initialize JdbcManager

   S2ContainerFactory.configure("app.dicon");
   S2Container container = S2ContainerFactory.getConfigurationContainer();
   JdbcManager jdbcManager = (JdbcManager) container.getComponent("jdbcManager"); // JdbcManager.class
   List accounts = jdbcManager.from(Account.class).getResultList();
   

7. [JdbcManager] Initialize DataSourceFactory to change database

   a. Create class CustomDataSourceFactoryImpl extends DataSourceFactoryImpl to set default database where no DataSourceName specified

   public class CustomDataSourceFactoryImpl extends DataSourceFactoryImpl {
     @Override
     public String getSelectableDataSourceName() {
       String name = (String) selectableDataSourceName.get();
       if (name == null) {
         name = "db"; // default database
       }
       return name;
     }
   }
   

   b. Declare component dataSource and dataSourceFactory in jdbc.dicon file

   <component name = "dataSource" class="org.seasar.extension.datasource.impl.SelectableDataSourceProxy"/>
   <component name = "dataSourceFactory" class="mypackage.CustomDataSourceFactoryImpl"/>
   

   c. Create DataSourceFactory to change database

   S2ContainerFactory.configure("app.dicon");
   S2Container container = S2ContainerFactory.getConfigurationContainer();
   DataSourceFactory dataSourceFactory = (DataSourceFactory) container.getComponent("dataSourceFactory"); // DataSourceFactory.class
   dataSourceFactory.setSelectableDataSourceName("db1");