| // Copyright 2008 Google Inc. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package com.google.gwtorm.jdbc; |
| |
| import com.google.gwtorm.client.OrmException; |
| import com.google.gwtorm.client.Schema; |
| import com.google.gwtorm.client.Transaction; |
| import com.google.gwtorm.schema.RelationModel; |
| import com.google.gwtorm.schema.SchemaModel; |
| import com.google.gwtorm.schema.SequenceModel; |
| import com.google.gwtorm.schema.sql.SqlDialect; |
| |
| import java.sql.Connection; |
| import java.sql.ResultSet; |
| import java.sql.SQLException; |
| import java.sql.Statement; |
| |
| /** Internal base class for implementations of {@link Schema}. */ |
| public abstract class JdbcSchema implements Schema { |
| private final Database<?> dbDef; |
| private Connection conn; |
| |
| protected JdbcSchema(final Database<?> d, final Connection c) { |
| dbDef = d; |
| conn = c; |
| } |
| |
| public final Connection getConnection() { |
| return conn; |
| } |
| |
| public void createSchema() throws OrmException { |
| final SqlDialect dialect = dbDef.getDialect(); |
| final SchemaModel model = dbDef.getSchemaModel(); |
| try { |
| final Statement stmt; |
| |
| stmt = getConnection().createStatement(); |
| try { |
| for (final SequenceModel s : model.getSequences()) { |
| stmt.execute(s.getCreateSequenceSql(dialect)); |
| } |
| for (final RelationModel r : model.getRelations()) { |
| stmt.execute(r.getCreateTableSql(dialect)); |
| } |
| } finally { |
| stmt.close(); |
| } |
| } catch (SQLException e) { |
| throw new OrmException("Schema creation failure", e); |
| } |
| } |
| |
| protected long nextLong(final String query) throws OrmException { |
| try { |
| final Statement st = getConnection().createStatement(); |
| try { |
| final ResultSet rs = st.executeQuery(query); |
| try { |
| if (!rs.next()) { |
| throw new SQLException("No result row for sequence query"); |
| } |
| final long r = rs.getLong(1); |
| if (rs.next()) { |
| throw new SQLException("Too many results from sequence query"); |
| } |
| return r; |
| } finally { |
| rs.close(); |
| } |
| } finally { |
| st.close(); |
| } |
| } catch (SQLException e) { |
| throw new OrmException("Sequence query failed", e); |
| } |
| } |
| |
| public Transaction beginTransaction() { |
| return new JdbcTransaction(this); |
| } |
| |
| public void close() { |
| if (conn != null) { |
| try { |
| conn.close(); |
| } catch (SQLException err) { |
| // TODO Handle an exception while closing a connection |
| } |
| conn = null; |
| } |
| } |
| } |