| Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
| SequenceManager |
|
| 1.0;1 |
| 1 | package org.apache.ojb.broker.util.sequence; | |
| 2 | ||
| 3 | /* Copyright 2002-2005 The Apache Software Foundation | |
| 4 | * | |
| 5 | * Licensed under the Apache License, Version 2.0 (the "License"); | |
| 6 | * you may not use this file except in compliance with the License. | |
| 7 | * You may obtain a copy of the License at | |
| 8 | * | |
| 9 | * http://www.apache.org/licenses/LICENSE-2.0 | |
| 10 | * | |
| 11 | * Unless required by applicable law or agreed to in writing, software | |
| 12 | * distributed under the License is distributed on an "AS IS" BASIS, | |
| 13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
| 14 | * See the License for the specific language governing permissions and | |
| 15 | * limitations under the License. | |
| 16 | */ | |
| 17 | ||
| 18 | import org.apache.ojb.broker.accesslayer.JdbcAccess; | |
| 19 | import org.apache.ojb.broker.metadata.ClassDescriptor; | |
| 20 | import org.apache.ojb.broker.metadata.FieldDescriptor; | |
| 21 | ||
| 22 | /** | |
| 23 | * SequenceManagers are responsible for creating new unique | |
| 24 | * ID's - unique accross all "extent" object declarations in OJB metadata. | |
| 25 | * There are some standard sequence manager implementations in | |
| 26 | * this package. | |
| 27 | * <p/> | |
| 28 | * SequenceManager objects are obtained from a factory class called | |
| 29 | * {@link SequenceManagerFactory}. | |
| 30 | * This Factory can be configured to provide instances of user defined | |
| 31 | * implementors of this interface. | |
| 32 | * <p/> | |
| 33 | * NOTE: SequenceManagers should be aware of "extents" ("extent" is an OJB inheritance feature), | |
| 34 | * that is: if you ask for an uid for an Interface (more exact for one implementor class) | |
| 35 | * with several implementor classes, or a baseclass with several subclasses the returned uid | |
| 36 | * should be unique accross all tables representing objects of the extent in question. | |
| 37 | * | |
| 38 | * @version $Id: SequenceManager.java,v 1.1 2007-08-24 22:17:29 ewestfal Exp $ | |
| 39 | */ | |
| 40 | public interface SequenceManager | |
| 41 | { | |
| 42 | /** | |
| 43 | * This method is called to get an unique value <strong>before</strong> the object | |
| 44 | * is written to persistent storage. | |
| 45 | * <br/> | |
| 46 | * Returns a unique object for the given field attribute. | |
| 47 | * The returned value takes in account the jdbc-type | |
| 48 | * and the FieldConversion.sql2java() conversion defined for <code>field</code>. | |
| 49 | * The returned object is unique accross all tables of "extent" classes the | |
| 50 | * field belongs to. | |
| 51 | * <br/> | |
| 52 | * Implementations using native identity columns should return a unique | |
| 53 | * incremented counter object for temporary use by OJB. | |
| 54 | */ | |
| 55 | public Object getUniqueValue(FieldDescriptor field) throws SequenceManagerException; | |
| 56 | ||
| 57 | /** | |
| 58 | * This method is called <strong>after</strong> the object was written to the persistent storage. | |
| 59 | * <br/> | |
| 60 | * This is to support native Identity columns (auto_increment columns) on the db side. | |
| 61 | * Other implementations may ignore this method. | |
| 62 | * @param dbAccess Current used {@link org.apache.ojb.broker.accesslayer.JdbcAccess} instance | |
| 63 | * @param cld Descriptor for specified object | |
| 64 | * @param obj The object to associate with identity value | |
| 65 | */ | |
| 66 | public void afterStore(JdbcAccess dbAccess, ClassDescriptor cld, Object obj) throws SequenceManagerException; | |
| 67 | } |