Invoking Button Action Programmatically,Queuing ActionEvent

Sometimes we need to invoke any button's action in bean without pressing that button,
as you have to call button action on any component's value change Listener- So how to do this in ADF managed bean.
ADF provides facility to queue action one after another, means you can perform multiple action by queuing 

I am using bounded task flow with page fragments(.jsff)-

• Create a button in page fragment and define ActionListener in managed bean
• Now I have created a input text and its valueChangeListener in managed bean
• I wish to call button' ActionListener in my input text valueChangeListener .





• we can do this by writing this code snippet on valueChangeListener 


public void callAceVCE(ValueChangeEvent vce) {
if (vce.getNewValue() != null) {
//Code to call ActionEvent
FacesContext facesContext = FacesContext.getCurrentInstance();
UIViewRoot root = facesContext.getViewRoot();
/**Pass cb1(buttonId) if page is not in taskflow, else if page is inside region then pass rgionid:buttonId*/
RichCommandButton button = (RichCommandButton)root.findComponent("r1:cb1");
ActionEvent actionEvent = new ActionEvent(button);
actionEvent.queue();
}
}

•  Now run your page and when you will change input text value - button actionListener will be called

Global Exception Handler for ADF Task Flow Method Calls

Exception Handler is the central point for handling unexpected Exceptions that are thrown during the Faces lifecycle.
ADF Task Flow provides this facility, using this you can handle all exception that raised in TaskFlow methods.
here i am using ADF bounded TaskFlow with page fragments(.jsff) .
Developers must use this facility to avoid unexpected exception inside taskflows.

This is very simple approach , you have to do nothing more but create a method in Task Flow and mark it as Exception Handler and write your code inside this method , that you want to show when any exception is caught in TaskFlow.

To implement this i have implemented this scenario-

• Create a method that throw an Exception and add it to taskFlow, and on page call this method on button click


public void exception() {
throw new JboException("Failded to load");
}

• When we click on button that call exception() method ,JboException is raised inside TaskFlow and look like this- Your page crashed

• Now create a method that will behave as ExceptionHandeler  and add it to TaskFlow and mark as Exception Handeler (Symbol in Jdev toolbar for marking)


public void exceptioHandeler() {
System.out.println("Inside Handeler");
FacesMessage message = new FacesMessage("This is custom Message for Jbo Exception-Exception Handeler");
message.setSeverity(FacesMessage.SEVERITY_WARN);
FacesContext fc = FacesContext.getCurrentInstance();
fc.addMessage(null, message);

}

• Use this sign to mark method as Exception Handeler in bounded Task Flow

• Now Run your page and click on button that call exception() method, your page never crash, as there is handler

Find Sample application Download Sample ADF Application

Currency- A Java Utility, Get currency code , symbol using Locale in Java

Java provides utility classes inside java.util package.

java.util.Currency is very interesting class in this package,it represents currencies defined in ISO 4217 by 

their currency codes.

You can get currency codes, its symbol, default fraction digits using its method.

java.lang.Object
  java.util.Currency 

see this short example , how we use Currency Class in Java,You can also get 

live currency fluctuation in java using Currency Converter API

package practiceJava;

import java.util.Currency;
import java.util.Locale;

public class CurrencyDemo {

    public static void main(String[] args) {
        // create a currency object with  locale
        Locale locale = Locale.US;
        Currency curr = Currency.getInstance(locale);
        System.out.println("Locale's currency code:" + curr.getCurrencyCode());
        // Get symbol for Currecny
        String symbol = curr.getSymbol();
        System.out.println("Symbol is :" + symbol);
        // Get default fraction digit for Currecny
        int frDigit = curr.getDefaultFractionDigits();
        System.out.println("Default fraction digit : " + frDigit);

    }
}

Output look like this