ResultSetIterator.java

package jdbc;

import java.io.Closeable;
import java.io.IOException;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Iterator;

/**
 * A Closable iterator over a ResultSet. Returns the first column as an object
 **/
public class ResultSetIterator<T> implements Iterator<T>, Closeable {

    private ResultSet resultSet;

    public ResultSetIterator(ResultSet resultSet) {
        this.resultSet = resultSet;
    }

    @Override
    public boolean hasNext() {
        try {
            return resultSet.next();
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public T next() {
        try {
            return (T) resultSet.getObject(1);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public void close() throws IOException {
        try {
            resultSet.close();
        } catch (SQLException e) {
            throw new IOException(e);
        }
    }

    @Override
    public void remove() {
        throw new UnsupportedOperationException();
    }
}