How to pass parameters in request - Java server Faces ?

use utility class like ==>

 package com.salpe.util; 
import javax.faces.context.FacesContext; 
public class FacesUtil{ 
/** * @param key 
* @return */ 
public static Object getRequestParameter(String key) { 
return FacesContext.getCurrentInstance().getExternalContext().getRequestMap().get(key); 
} 
/** * @param key 
* @param value */ 
public static void setRequestParameter(String key, Object value) { 
FacesContext.getCurrentInstance().getExternalContext().getRequestMap().put(key, value); 
} 
} 

Then in any backing bean :

 package com.salpe.authentication.managedbeans; 
import com.salpe.util; 
public class LoginPageBean { 
LoginPageBean (){ 
} 
// Action button for submit on login page 
public actionSubmit(){ 
// Do anything logical 
FacesUtil.setParameter("backPage" , "FromLoginPage") 
return "welcomePage" ; 
} 
} 

 package com.salpe.managedbeans; 
import com.salpe.util; 
public class WelcomeBean{ 
WelcomeBean(){ 
String fromPage = FacesUtil.getParameter("backPage") 
System.out.println( " Came from " + fromPage ); 
} 
}