Similarity that disregards the length of the field.

gistfile1.java

    private final static Similarity NO_LENGTH_SIMILARITY = new DefaultSimilarity() {

        // we are interested in length norm for the street number field.
        // it's good if 10 is sorted before 10a and 10b.
        //
        // the "country" field is very important it has no document boost since that means
        // simply turning Query.setCountry() on will make a different score. This is because
        // a document boost will add to every field and country is matched in a MUST.
        @Override
        public float computeNorm(String field, FieldInvertState state) {

            if (AddressImpl.Fields.STREET_NO.iname().equals(field)) {

                return super.computeNorm(field, state);

            } else {

                return state.getBoost();

            }

        }


        // overridden to return 1.0f
        @Override
        public float idf(int docFreq, int numDocs) {
            return 1.0f;
        }


        // overridden to return 1.0f
        @Override
        public float queryNorm(float sumOfSquaredWeights) {
            return 1.0f;
        };


        // overridden to return 1.0f
        @Override
        public float coord(int overlap, int maxOverlap) {
            return 1.0f;
        };


        // overridden to return 1.0f
        @Override
        public float tf(float freq) {
            return 1.0f;
        }


        // we only expect values to be integer between 0-100
        @Override
        public byte encodeNormValue(float f) {
            return (byte) f;
        }


        @Override
        public float decodeNormValue(byte b) {
            return (float) b;
        };

    };