001 /* JAPI - (Yet another (hopefully) useful) Java API
002 *
003 * Copyright (C) 2004-2006 Christian Hujer
004 *
005 * This program is free software; you can redistribute it and/or
006 * modify it under the terms of the GNU General Public License as
007 * published by the Free Software Foundation; either version 2 of the
008 * License, or (at your option) any later version.
009 *
010 * This program is distributed in the hope that it will be useful, but
011 * WITHOUT ANY WARRANTY; without even the implied warranty of
012 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
013 * General Public License for more details.
014 *
015 * You should have received a copy of the GNU General Public License
016 * along with this program; if not, write to the Free Software
017 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
018 * 02111-1307, USA.
019 */
020
021 package net.sf.japi.sql;
022
023 import java.sql.ResultSet;
024 import java.sql.ResultSetMetaData;
025 import java.sql.SQLException;
026 import java.util.ArrayList;
027 import java.util.List;
028
029 /** A Helper Class to make work with JDBC less painful in some situations.
030 * @author <a href="mailto:chris@riedquat.de">Christian Hujer</a>
031 */
032 public class SQLHelper {
033
034 /** The Type information for a two-dimensional Object Array. */
035 private static final Object[][] OBJECT_ARRAY_ARRAY_INSTANCE = new Object[0][0];
036
037 /** Get a ResultSet's Column Names.
038 * The names are physical.
039 * For names for display @see #getColumnLabels(ResultSet).
040 * @param rs ResultSet
041 * @return column names
042 * @throws SQLException on SQL problems
043 */
044 public static String[] getColumnNames(final ResultSet rs) throws SQLException {
045 final ResultSetMetaData md = rs.getMetaData();
046 final int columnCount = md.getColumnCount();
047 final String[] columnNames = new String[columnCount];
048 for (int i = 0; i < columnCount; i++) {
049 columnNames[i] = md.getColumnName(i + 1);
050 }
051 return columnNames;
052 }
053
054 /** Get a ResultSet's Column Labels.
055 * The names are for display.
056 * For physical names @see #getColumnNames(ResultSet).
057 * @param rs ResultSet
058 * @return column labels
059 * @throws SQLException on SQL problems
060 */
061 public static String[] getColumnLabels(final ResultSet rs) throws SQLException {
062 final ResultSetMetaData md = rs.getMetaData();
063 final int columnCount = md.getColumnCount();
064 final String[] columnNames = new String[columnCount];
065 for (int i = 0; i < columnCount; i++) {
066 columnNames[i] = md.getColumnLabel(i + 1);
067 }
068 return columnNames;
069 }
070
071 /** Get a ResultSet's result.
072 * @param rs ResultSet
073 * @return two-dimensional Array containing the results
074 * @throws SQLException on SQL problems
075 */
076 public static Object[][] getData(final ResultSet rs) throws SQLException {
077 final List<Object[]> resultList = new ArrayList<Object[]>();
078 final ResultSetMetaData md = rs.getMetaData();
079 final int columnCount = md.getColumnCount();
080 while (rs.next()) {
081 final Object[] row = new Object[columnCount];
082 for (int i = 0; i < columnCount; i++) {
083 row[i] = rs.getObject(i + 1);
084 }
085 resultList.add(row);
086 }
087 return resultList.toArray(OBJECT_ARRAY_ARRAY_INSTANCE);
088 }
089
090 /** Get a ResultSet's size.
091 * Warning: The ResultSet's Cursor is moved by invoking this method!
092 * @param rs ResultSet
093 * @return the number of rows in this ResultSet
094 * @throws SQLException on SQL problems
095 */
096 public static int getRowCount(final ResultSet rs) throws SQLException {
097 return rs.last() ? rs.getRow() : 0;
098 }
099
100 } // class SQLHelper