DiscardingModel.java

package be.selckin.swu.model;

import com.google.common.base.Preconditions;
import org.apache.wicket.model.IModel;

public class DiscardingModel<T> implements IModel<T> {
    private transient T obj;

    public DiscardingModel(T obj) {
        Preconditions.checkNotNull(obj);
        this.obj = obj;
    }

    @Override
    public T getObject() {
        Preconditions.checkNotNull(obj, "Attempting to use a detached discarding model");
        return obj;
    }

    @Override
    public void setObject(T object) {
        this.obj = object;
    }

    @Override
    public void detach() {
        obj = null;
    }

    public static <T> DiscardingModel<T> of(T t) {
        return new DiscardingModel<T>(t);
    }
}