一起飞的更高

public class FacesUtils {
/**
* Get servlet context.
*
* @return the servlet context
*/
public static ServletContext getServletContext() {
return (ServletContext)FacesContext.getCurrentInstance().getExternalContext().getContext();
}

/**
* Get managed bean based on the bean name.
*
* @param beanName the bean name
* @return the managed bean associated with the bean name
*/
public static Object getManagedBean(String beanName) {
Object o = getValueBinding(getJsfEl(beanName)).getValue(FacesContext.getCurrentInstance());

return o;
}

/**
* Remove the managed bean based on the bean name.
*
* @param beanName the bean name of the managed bean to be removed
*/
public static void resetManagedBean(String beanName) {
getValueBinding(getJsfEl(beanName)).setValue(FacesContext.getCurrentInstance(), null);
}

/**
* Store the managed bean inside the session scope.
*
* @param beanName the name of the managed bean to be stored
* @param managedBean the managed bean to be stored
*/
public static void setManagedBeanInSession(String beanName, Object managedBean) {
FacesContext.getCurrentInstance().getExternalContext().getSessionMap().put(beanName, managedBean);
}

/**
* Get parameter value from request scope.
*
* @param name the name of the parameter
* @return the parameter value
*/
public static String getRequestParameter(String name) {
return (String)FacesContext.getCurrentInstance().getExternalContext().getRequestParameterMap().get(name);
}

/**
* Get <code>ApplicationBean</code>.
* <p>
* Specific for this application.
*
* @return the application bean
*/
public static ApplicationBean getApplicationBean() {
return (ApplicationBean)getManagedBean(BeanNames.APPLICATION_BEAN);
}

/**
* Get <code>SessionBean</code>.
* <p>
* Specific for this applicaiton.
*
* @return the session bean
*/
public static SessionBean getSessionBean() {
return (SessionBean)getManagedBean(BeanNames.SESSION_BEAN);
}

/**
* Add information message.
*
* @param msg the information message
*/
public static void addInfoMessage(String msg) {
addInfoMessage(null, msg);
}

/**
* Add information message to a sepcific client.
*
* @param clientId the client id
* @param msg the information message
*/
public static void addInfoMessage(String clientId, String msg) {
FacesContext.getCurrentInstance().addMessage(clientId, new FacesMessage(FacesMessage.SEVERITY_INFO, msg, msg));
}

/**
* Add error message.
*
* @param msg the error message
*/
public static void addErrorMessage(String msg) {
addErrorMessage(null, msg);
}

/**
* Add error message to a sepcific client.
*
* @param clientId the client id
* @param msg the error message
*/
public static void addErrorMessage(String clientId, String msg) {
FacesContext.getCurrentInstance().addMessage(clientId, new FacesMessage(FacesMessage.SEVERITY_ERROR, msg, msg));
}

/**
* Evaluate the integer value of a JSF expression.
*
* @param el the JSF expression
* @return the integer value associated with the JSF expression
*/
public static Integer evalInt(String el) {
if (el == null) {
return null;
}

if (UIComponentTag.isValueReference(el)) {
Object value = getElValue(el);

if (value == null) {
return null;
}
else if (value instanceof Integer) {
return (Integer)value;
}
else {
return new Integer(value.toString());
}
}
else {
return new Integer(el);
}
}

private static Application getApplication() {
ApplicationFactory appFactory = (ApplicationFactory)FactoryFinder.getFactory(FactoryFinder.APPLICATION_FACTORY);
return appFactory.getApplication();
}

private static ValueBinding getValueBinding(String el) {
return getApplication().createValueBinding(el);
}

private static HttpServletRequest getServletRequest() {
return (HttpServletRequest)FacesContext.getCurrentInstance().getExternalContext().getRequest();
}

private static Object getElValue(String el) {
return getValueBinding(el).getValue(FacesContext.getCurrentInstance());
}

private static String getJsfEl(String value) {
return "#{" + value + "}";
}
}