ScalarConverter.java

package org.caudexorigo.jdbc;

import java.sql.ResultSet;
import java.sql.SQLException;

import org.apache.commons.lang3.StringUtils;

public class ScalarConverter<T> implements RowConverter<T>
{
	private int columnIndex;
	private String columnName;
	private final Class<T> clazz;

	public ScalarConverter(int columnIndex, Class<T> clazz)
	{
		super();
		this.columnIndex = columnIndex;
		this.clazz = clazz;
	}

	public ScalarConverter(String columnName, Class<T> clazz)
	{
		super();
		this.columnName = columnName;
		this.clazz = clazz;
	}

	@Override
	public T process(ResultSet rs)
	{
		if ((columnIndex < 1) && (StringUtils.isBlank(columnName)))
		{
			throw new IllegalStateException("A column name or a column index must be suplied");
		}

		try
		{
			if ((columnIndex >= 1) && (StringUtils.isBlank(columnName)))
			{
				return getValue(rs, columnIndex);
			}
			else
			{
				return getValue(rs, columnName);
			}
		}
		catch (SQLException e)
		{
			throw new RuntimeException(e);
		}
	}

	private T getValue(ResultSet rs, int ix) throws SQLException
	{
		return clazz.cast(rs.getObject(ix));
	}

	private T getValue(ResultSet rs, String field) throws SQLException
	{
		return clazz.cast(rs.getObject(field));
	}
}