Custom Converter Spring 2.5 / Spring webflow

1. Dispatcher Servlet configuration

 <bean id="viewResolver"  
           class="org.springframework.web.servlet.view.ResourceBundleViewResolver"  
           p:basename="views" />  
 <bean id="tilesConfigurer"  
           class="org.springframework.web.servlet.view.tiles2.TilesConfigurer"  
           p:definitions="/WEB-INF/tiles-defs.xml" />  
 <flow:flow-builder-services id="flowBuilderServices"  
           view-factory-creator="viewFactoryCreator" conversion-service="conversionService" />  

2. Write Convert Class

java.util.Calendar to String Custom Converter / String to java.util.Calendar Custom Converter

 import java.text.DateFormat;  
 import java.text.ParseException;  
 import java.text.SimpleDateFormat;  
 import java.util.Calendar;  
 import org.springframework.binding.convert.converters.TwoWayConverter;  
 public class CalendarStringTwoWayConverter implements TwoWayConverter {  
      @Override  
      public Class getSourceClass() {  
           return Calendar.class;  
      }  
      @Override  
      public Class getTargetClass() {  
           return String.class;  
      }  
      @Override  
      public Object convertSourceToTargetClass(Object source, Class targetClass)  
                throws Exception {  
           String date = null;  
           DateFormat dateFormat = new SimpleDateFormat("MM/dd/yyyy");  
           if(null!=source){  
                date= dateFormat.format(((Calendar) source).getTime()).toString();  
           }  
           return date;  
      }  
      @Override  
      public Object convertTargetToSourceClass(Object target, Class sourceClass)  
                throws Exception {  
            Calendar cal = Calendar.getInstance();  
         SimpleDateFormat sdf = new SimpleDateFormat("MM/dd/yyyy");  
         try {  
                 cal.setTime(sdf.parse((String) target));  
            } catch (ParseException e) {  
                 e.printStackTrace();  
            }  
           return cal;  
      }  
 }  

3. Register Converter

 import org.springframework.binding.convert.service.DefaultConversionService;  
 import org.springframework.stereotype.Component;  
 @Component("conversionService")  
 public class ApplicationConversionService extends DefaultConversionService {  
      @Override  
      protected void addDefaultConverters() {  
           super.addDefaultConverters();  
           addDefaultAliases();  
           addConverter("calenderStringTwoWayConverter", new CalendarStringTwoWayConverter());  
           addConverter("enumStringTwoWayConverter", new EnumStringTwoWayConverter());  
           addConverter("timeStringTwoWayConverter", new TimeStringTwoWayConverter());  
      }  
 }  

Use in flow registry : Bind  properties with converter

 <view-state id="review" view="review" model="reviewModel">  
      <binder>  
           <binding property="state" converter="enumStringTwoWayConverter"/>            
           <binding property="time" converter="timeStringTwoWayConverter"/>             
           <binding property="date" converter="calenderStringTwoWayConverter"/>   
      </binder>  
 </view-state>  

This way of using named converters has been discontinued from Spring 3.0. In Spring3.0 the converters are handled in a different way.

4. Use in JSP

There is nothing special in jsp.

 <form:form name="myform" modelAttribute="reviewModel">  
      <form:input type="text" id="date" path="date" value="${date}"/>  
 </form:form>