package org.jbpm.jsf.core.action;
import org.jbpm.jsf.JbpmActionListener;
import org.jbpm.jsf.JbpmJsfContext;
import javax.el.ELContext;
import javax.el.ValueExpression;
import javax.faces.context.FacesContext;
import javax.faces.event.ActionEvent;
/**
*
*/
public final class LazyJbpmActionListener implements JbpmActionListener {
private final ValueExpression typeExpression;
private final ValueExpression listenerExpression;
public LazyJbpmActionListener(final ValueExpression typeExpression, final ValueExpression listenerExpression) {
this.typeExpression = typeExpression;
this.listenerExpression = listenerExpression;
}
public String getName() {
return "jbpmActionListener";
}
public void handleAction(JbpmJsfContext context, ActionEvent event) {
final FacesContext facesContext = FacesContext.getCurrentInstance();
final ELContext elContext = facesContext.getELContext();
final JbpmActionListener listener;
if (typeExpression != null) {
final Object typeValue = typeExpression.getValue(elContext);
if (typeValue == null) {
context.setError("Error calling action listener", "The type value is null");
return;
}
final Class type;
if (typeValue instanceof Class) {
type = (Class) typeValue;
} else {
final String className = typeValue.toString();
try {
type = Class.forName(className);
} catch (ClassNotFoundException e) {
context.setError("Error calling action listener", "The class '" + className + "' was not found");
return;
}
}
if (! JbpmActionListener.class.isAssignableFrom(type)) {
context.setError("Error calling action listener", "The class '" + type.getName() + "' is not a valid JbpmActionListener");
return;
}
try {
listener = (JbpmActionListener) type.newInstance();
} catch (Exception e) {
context.setError("Error calling action listener", e);
return;
}
} else if (listenerExpression != null) {
final Object listenerValue = listenerExpression.getValue(elContext);
if (listenerValue == null) {
context.setError("Error calling action listener", "The listener value is null");
return;
}
if (! (listenerValue instanceof JbpmActionListener)) {
context.setError("Error calling action listener", "The listener value given is not a valid JbpmActionListener");
return;
}
listener = (JbpmActionListener) listenerValue;
} else {
context.setError("Error calling action listener", "Either a type or a listener must be given");
return;
}
listener.handleAction(context, event);
}
}