| // 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.KeyUtil; |
| import com.google.gwtorm.schema.RelationModel; |
| import com.google.gwtorm.schema.SchemaModel; |
| import com.google.gwtorm.schema.java.JavaSchemaModel; |
| import com.google.gwtorm.schema.sql.SqlDialect; |
| import com.google.gwtorm.server.GeneratedClassLoader; |
| import com.google.gwtorm.server.OrmException; |
| import com.google.gwtorm.server.Schema; |
| import com.google.gwtorm.server.SchemaConstructorGen; |
| import com.google.gwtorm.server.SchemaFactory; |
| import com.google.gwtorm.server.SchemaGen; |
| import com.google.gwtorm.server.StandardKeyEncoder; |
| import java.sql.Connection; |
| import java.sql.SQLException; |
| import javax.sql.DataSource; |
| |
| /** |
| * Constructor for application {@link Schema} extensions. |
| * |
| * <p>Applications should use the Database class to create instances of their Schema extension |
| * interface, and thus open and connect to the JDBC data store. |
| * |
| * <p>Creating a new Database instance is expensive, due to the type analysis and code generation |
| * performed to implement the Schema and Access interfaces. Applications should create and cache |
| * their Database instance for the live of the application. |
| * |
| * <p>Database instances are thread-safe, but returned Schema instances are not. |
| * |
| * @param <T> |
| */ |
| public class Database<T extends Schema> implements SchemaFactory<T> { |
| static { |
| KeyUtil.setEncoderImpl(new StandardKeyEncoder()); |
| } |
| |
| private final DataSource dataSource; |
| private final JavaSchemaModel schemaModel; |
| private final SchemaFactory<T> implFactory; |
| private final SqlDialect implDialect; |
| |
| /** |
| * Create a new database interface, generating the interface implementations. |
| * |
| * @param ds JDBC connection information |
| * @param schema application extension of the Schema interface to implement. |
| * @throws OrmException the schema interface is incorrectly defined, or the driver class is not |
| * available through the current class loader. |
| */ |
| public Database(final DataSource ds, final Class<T> schema) throws OrmException { |
| dataSource = ds; |
| |
| SqlDialect dialect; |
| try { |
| Connection c = ds.getConnection(); |
| try { |
| dialect = SqlDialect.getDialectFor(c); |
| } finally { |
| c.close(); |
| } |
| } catch (SQLException e) { |
| throw new OrmException("Unable to determine SqlDialect", e); |
| } |
| |
| schemaModel = new JavaSchemaModel(schema); |
| final GeneratedClassLoader loader = newLoader(schema); |
| final Class<T> impl = generate(dialect, loader); |
| implFactory = new SchemaConstructorGen<>(loader, impl, this).create(); |
| implDialect = dialect; |
| } |
| |
| @SuppressWarnings({"unchecked", "rawtypes"}) |
| private Class<T> generate(final SqlDialect dialect, final GeneratedClassLoader loader) |
| throws OrmException { |
| return new SchemaGen( |
| loader, |
| schemaModel, |
| getClass(), |
| JdbcSchema.class, |
| new SchemaGen.AccessGenerator() { |
| @Override |
| public Class<?> create(GeneratedClassLoader loader, RelationModel rm) |
| throws OrmException { |
| return new AccessGen(loader, rm, dialect).create(); |
| } |
| }) |
| .create(); |
| } |
| |
| SqlDialect getDialect() { |
| return implDialect; |
| } |
| |
| SchemaModel getSchemaModel() { |
| return schemaModel; |
| } |
| |
| /** |
| * Open a new connection to the database and get a Schema wrapper. |
| * |
| * @return a new JDBC connection, wrapped up in the application's Schema. |
| * @throws OrmException the connection could not be opened to the database. The JDBC exception |
| * detail should be examined to determine the root cause of the connection failure. |
| */ |
| @Override |
| public T open() throws OrmException { |
| return implFactory.open(); |
| } |
| |
| Connection newConnection() throws OrmException { |
| final Connection conn; |
| try { |
| conn = dataSource.getConnection(); |
| } catch (SQLException e) { |
| throw new OrmException("Cannot open database connection", e); |
| } |
| |
| try { |
| if (!conn.getAutoCommit()) { |
| conn.setAutoCommit(true); |
| } |
| } catch (SQLException e) { |
| try { |
| conn.close(); |
| } catch (SQLException e2) { |
| } |
| throw new OrmException("Cannot force auto-commit on connection", e); |
| } |
| return conn; |
| } |
| |
| private static <T> GeneratedClassLoader newLoader(final Class<T> schema) { |
| return new GeneratedClassLoader(schema.getClassLoader()); |
| } |
| } |