org.eclipse.persistence.descriptors.RelationalDescriptor Maven / Gradle / Ivy
/*******************************************************************************
* Copyright (c) 1998, 2012 Oracle and/or its affiliates. All rights reserved.
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
* which accompanies this distribution.
* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
* and the Eclipse Distribution License is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* Contributors:
* Oracle - initial API and implementation from Oracle TopLink
*
******************************************************************************/
package org.eclipse.persistence.descriptors;
import java.util.*;
import org.eclipse.persistence.exceptions.*;
import org.eclipse.persistence.internal.descriptors.VirtualAttributeMethodInfo;
/**
* Purpose: EclipseLink has been designed to take advantage of the similarities between
* relational databases and objects while accommodating for their differences, providing an object
* oriented wrapper for relational databases. This is accomplished through the use of Descriptors.
* A descriptor is a pure specification class with all its behavior deputized to DescriptorEventManager,
* DescriptorQueryManager and ObjectBuilder. Look at the following variables for the list
* of specification on the descriptor.
*
* A Descriptor is a set of mappings that describe how an objects's data is to be represented in a
* relational database. It contains mappings from the class instance variables to the table's fields,
* as well as the transformation routines necessary for storing and retrieving attributes. As such
* the descriptor acts as the link between the Java object and its database representation.
*
* Every descriptor is initialized with the following information:
*
* - The Java class its describes, and the corresponding table(s) for storing instances of the class.
*
- The primary key of the table.
*
- A list of query keys for field names.
*
- A description of the objects's attributes and relationships. This information is stored in mappings.
*
- A set of user selectable properties for tailoring the behavior of the descriptor.
*
*
* This descriptor subclass should be used for object-relational mapping,
* and allows for other datatype mappings to be done in the XML, EIS and OR sibling classes.
*
* @see DescriptorEventManager
* @see DescriptorQueryManager
* @see InheritancePolicy
* @see InterfacePolicy
*/
public class RelationalDescriptor extends ClassDescriptor {
/** This flag stores whether this descriptor is using Property access based on JPA semantics. It is used to modify
* the behavior of our weaving functionality as it pertains to adding annotations to fields
*/
protected boolean weavingUsesPropertyAccess = false;
/** A list of methods that are used by virtual mappings. This list is used to control weaving of methods
* used for virtual access*/
protected List virtualAttributeMethods = null;
/**
* PUBLIC:
* Return a new descriptor.
*/
public RelationalDescriptor() {
super();
this.virtualAttributeMethods = new ArrayList();
}
/**
* PUBLIC:
* Specify the table name for the class of objects the receiver describes.
* If the table has a qualifier it should be specified using the dot notation,
* (i.e. "userid.employee"). This method is used if there is more than one table.
*/
public void addTableName(String tableName) {
super.addTableName(tableName);
}
/**
* PUBLIC:
* Return the name of the descriptor's first table.
* This method must only be called on single table descriptors.
*/
public String getTableName() {
return super.getTableName();
}
/**
* PUBLIC:
* Return the table names.
*/
public Vector getTableNames() {
return super.getTableNames();
}
/**
* INTERNAL:
* Return the list of virtual methods sets for this Entity.
* This list is used to control which methods are weaved
**/
public List getVirtualAttributeMethods() {
return virtualAttributeMethods;
}
/**
* PUBLIC:
* The descriptors default table can be configured if the first table is not desired.
*/
public void setDefaultTableName(String defaultTableName) {
super.setDefaultTableName(defaultTableName);
}
/**
* PUBLIC:
* Specify the table name for the class of objects the receiver describes.
* If the table has a qualifier it should be specified using the dot notation,
* (i.e. "userid.employee"). This method is used for single table.
*/
public void setTableName(String tableName) throws DescriptorException {
super.setTableName(tableName);
}
/**
* PUBLIC:
* Specify the all table names for the class of objects the receiver describes.
* If the table has a qualifier it should be specified using the dot notation,
* (i.e. "userid.employee"). This method is used for multiple tables
*/
public void setTableNames(Vector tableNames) {
super.setTableNames(tableNames);
}
/**
* PUBLIC: Set the table Qualifier for this descriptor. This table creator will be used for
* all tables in this descriptor
*/
public void setTableQualifier(String tableQualifier) {
super.setTableQualifier(tableQualifier);
}
/**
* INTERNAL:
* Set the list of methods used my mappings with virtual access
* this list is used to determine which methods to weave
*/
public void setVirtualAttributeMethods(List virtualAttributeMethods) {
this.virtualAttributeMethods = virtualAttributeMethods;
}
/**
* INTERNAL:
* Return whether this descriptor uses property access. This information is used to
* modify the behavior of some of our weaving features
*/
public boolean usesPropertyAccessForWeaving(){
return weavingUsesPropertyAccess;
}
/**
* INTERNAL:
* Record that this descriptor uses property access. This information is used to
* modify the behavior of some of our weaving features
*/
public void usePropertyAccessForWeaving(){
weavingUsesPropertyAccess = true;
}
}