public class NegotiationTypeBridge implements TwoWayFieldBridge
{

    @Override
    public void set(String name, Object value, Document document, LuceneOptions options)
    {
        if (!(value instanceof Set<?>))
        {
            throw new IllegalArgumentException("The object must be a Set.");
        }

        StringBuilder negotiations = new StringBuilder("");
        final String token = " ";

        @SuppressWarnings("unchecked")
        Set<NegotiationType> negotiationTypes = (Set<NegotiationType>) value;
        for (NegotiationType negotiationType : negotiationTypes)
        {
            negotiations.append(negotiationType.getDescription());
            negotiations.append(token);
        }

        Field field = new Field(name, negotiations.toString().trim(), options.getStore(),
                options.getIndex());
        if (options.getBoost() != null)
        {
            field.setBoost(options.getBoost());
        }
        document.add(field);
    }

    public Object get(String name, Document document)
    {
        Field field = (Field) document.getField("negotiationTypes");
        return field.stringValue();
    }

    public String objectToString(Object object)
    {
        String negotiationTypes = (String) object;
        return negotiationTypes;
    }
   
}

public class NegotiationTypeFilterFactory
{
    private String negotiationType;

    public void setNegotiationType(String negotiationType)
    {
        this.negotiationType = negotiationType;
    }

    @Factory
    public Filter buildFilter()
    {
        Term term = new Term("negotiationTypes", negotiationType);
        TermQuery query = new TermQuery(term);
        Filter filter = new QueryWrapperFilter(query);
        filter = new CachingWrapperFilter(filter);
        return filter;
    }

    @Key
    public FilterKey getKey()
    {
        StandardFilterKey key = new StandardFilterKey();
        key.addParameter(negotiationType);
        return key;
    }
}