nwillc

@FunctionalInterface
public interface Extractor<T> {
    /**
     * Extract type T from the current position in the ResultSet.
     *
     * @param rs the ResultSet to extract from
     * @return the type T extracted
     * @throws SQLException should the extraction fail
     */
    T extract(ResultSet rs) throws SQLException;

nwillc

public static <T, B> void copy(B bean,
    BiConsumer<B, T> setter,
    ResultSet rs,
    BiFunction<ResultSet, Integer, T> getter,
    Integer index) {
	setter.accept(bean, getter.apply(rs, index));
}

nwillc

BiFunction<ResultSet, Integer, String> STRING = (r, i) -> {
    try {
        return r.getString(i);
    } catch (SQLException e) {
        throw new RuntimeException(e);
    }
}

nwillc

class Example1 {
    final static BiFunction<ResultSet, Integer, String> STRING =
              (r, index) -> {
 	          try {
 		       return r.getString(index);
 		  } catch (SQLException e) {
 		       throw new RuntimeException(e);
 	       }
 	  };
    void example(ResultSet rs, Integer i) {

nwillc

public final class ExtractorFactory<B> {

    public ExtractorFactory<B> factory(Supplier<B> factory) { /* ... */ }

    public <T> ExtractorFactory<B> add(
        BiConsumer<B, T> setter,
        BiFunction<ResultSet, Integer, T> getter, 
        Integer index) { /* ... */ }

    public Extractor<B> getExtractor() { /* ... */ }

nwillc

class Example {
    final static BiFunction<ResultSet, Integer, String> STRING =
              (r, index) -> {
 	          try {
 		       return r.getString(index);
 		  } catch (SQLException e) {
 		       throw new RuntimeException(e);
 	       }
 	  };
    void example() {

nwillc

public final class ExtractorFactory<B> {
    private BiConsumer<B, ResultSet> consumer = (b, r) -> {};
    private Supplier<B> factory;

    public ExtractorFactory<B> factory(Supplier<B> factory) {
        this.factory = factory;
        return this;
    }

    public <T> ExtractorFactory<B> add(BiConsumer<B, T> setter,

nwillc

public final class Extractors {
    private Extractors() {}

    public static final BiFunction<ResultSet, Integer, String> STRING_I = (r, i) -> {
        try {
            return r.getString(i);
        } catch (SQLException e) {
            throw new UncheckedSQLException(e);
        }
    };

nwillc

@FunctionalInterface
public interface ThrowingBiFunction<T, U, R> extends BiFunction<T, U, R> {

	@Override
	default R apply(T t, U u) {
		try {
			return applyThrows(t, u);
		} catch (Exception e) {
			throw new RuntimeException(e);
		}

nwillc

public final class Extractors {
	private Extractors() {
	}

	public static final ThrowingBiFunction<ResultSet, Integer, String> STRING_I
		= ResultSet::getString;

	public static final ThrowingBiFunction<ResultSet, String, String> STRING_S 
		= ResultSet::getString;