ListItemModelAdapter.java

package be.selckin.swu.model;

import org.apache.wicket.model.IModel;

import java.util.List;

public class ListItemModelAdapter<T> implements IModel<T> {

    private final IModel<List<T>> listModel;
    private int index;

    public ListItemModelAdapter(IModel<List<T>> listModel, int index) {
        this.listModel = listModel;
        this.index = index;
    }

    @Override
    public T getObject() {
        return index < size() ? listModel.getObject().get(index) : null;
    }

    @Override
    public void setObject(T object) {
        listModel.getObject().set(index, object);
    }

    public int getIndex() {
        return index;
    }

    public int size() {
        return listModel.getObject().size();
    }

    @Override
    public void detach() {
        listModel.detach();
    }

    public boolean hasPrev() {
        return index > 0;
    }

    public void prev() {
        if (hasPrev())
            index--;
        else
            index = 0;
    }

    public void next() {
        if (hasNext())
            index++;
        else
            index = size() - 1;
    }

    public boolean hasNext() {
        return index < size() - 1;
    }

    public boolean isEmpty() {
        return listModel.getObject().isEmpty();
    }
}