diff options
Diffstat (limited to 'subsonic-backend/src/main/java/net/sourceforge/subsonic/backend/dao/schema/Schema.java')
-rw-r--r-- | subsonic-backend/src/main/java/net/sourceforge/subsonic/backend/dao/schema/Schema.java | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/subsonic-backend/src/main/java/net/sourceforge/subsonic/backend/dao/schema/Schema.java b/subsonic-backend/src/main/java/net/sourceforge/subsonic/backend/dao/schema/Schema.java new file mode 100644 index 00000000..850b82da --- /dev/null +++ b/subsonic-backend/src/main/java/net/sourceforge/subsonic/backend/dao/schema/Schema.java @@ -0,0 +1,66 @@ +/* + This file is part of Subsonic. + + Subsonic is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + Subsonic is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with Subsonic. If not, see <http://www.gnu.org/licenses/>. + + Copyright 2009 (C) Sindre Mehus + */ +package net.sourceforge.subsonic.backend.dao.schema; + +import org.springframework.jdbc.core.JdbcTemplate; + +/** + * Used for creating and evolving the database schema. + * + * @author Sindre Mehus + */ +public abstract class Schema { + + /** + * Executes this schema. + * @param template The JDBC template to use. + */ + public abstract void execute(JdbcTemplate template); + + /** + * Returns whether the given table exists. + * @param template The JDBC template to use. + * @param table The table in question. + * @return Whether the table exists. + */ + protected boolean tableExists(JdbcTemplate template, String table) { + try { + template.execute("select 1 from " + table); + } catch (Exception x) { + return false; + } + return true; + } + + /** + * Returns whether the given column in the given table exists. + * @param template The JDBC template to use. + * @param column The column in question. + * @param table The table in question. + * @return Whether the column exists. + */ + protected boolean columnExists(JdbcTemplate template, String column, String table) { + try { + template.execute("select " + column + " from " + table + " where 1 = 0"); + } catch (Exception x) { + return false; + } + return true; + } +} |