package com.dragome.forms.bindings.client.value;
import com.dragome.forms.bindings.client.interceptor.Interceptor;
import com.dragome.forms.bindings.client.interceptor.InterceptorChain;
import com.dragome.forms.bindings.extra.user.client.Command;
/**
* A ValueModel that can allows value changes to be intercepted by interested third parties. The
* interceptors can abort the value change if required.
*
* @see #interceptUsing(com.pietschy.gwt.pectin.client.interceptor.Interceptor)
*/
public class InterceptedValueHolder<T> extends ValueHolder<T> implements InterceptedMutableValueModel<T>
{
private InterceptorChain interceptors= new InterceptorChain();
public InterceptedValueHolder()
{
}
public InterceptedValueHolder(T value)
{
super(value);
}
@Override
public void setValue(final T newValue)
{
setValueInternal(newValue, false);
}
public void setValue(final T newValue, boolean force)
{
setValueInternal(newValue, force);
}
private void setValueInternal(final T newValue, boolean force)
{
if (force)
{
super.setValue(newValue);
}
else
{
interceptors.execute(new Command()
{
public void execute()
{
InterceptedValueHolder.super.setValue(newValue);
}
});
}
}
public void interceptUsing(Interceptor interceptor)
{
interceptors.addInterceptor(interceptor);
}
}