| /******************************************************************************* |
| * Copyright (c) 2008, 2011 Oracle. All rights reserved. |
| * This program and the accompanying materials are made available under the |
| * terms of the Eclipse Public License v1.0, which accompanies this distribution |
| * and is available at http://www.eclipse.org/legal/epl-v10.html. |
| * |
| * Contributors: |
| * Oracle - initial API and implementation |
| ******************************************************************************/ |
| package org.eclipse.jpt.jpa.db; |
| |
| import java.util.Comparator; |
| |
| import com.ibm.icu.text.Collator; |
| |
| /** |
| * Database foreign key |
| * <p> |
| * Provisional API: This interface is part of an interim API that is still |
| * under development and expected to change significantly before reaching |
| * stability. It is available at this early stage to solicit feedback from |
| * pioneering adopters on the understanding that any code that uses this API |
| * will almost certainly be broken (repeatedly) as the API evolves. |
| */ |
| public interface ForeignKey |
| extends DatabaseObject |
| { |
| // ********** tables ********** |
| |
| /** |
| * Return the foreign key's <em>base</em> table. |
| */ |
| Table getBaseTable(); |
| |
| /** |
| * Return the foreign key's <em>referenced</em> table. |
| */ |
| Table getReferencedTable(); |
| |
| |
| // ********** column pairs ********** |
| |
| /** |
| * Return the foreign key's column pairs. |
| */ |
| Iterable<ColumnPair> getColumnPairs(); |
| |
| /** |
| * Return the size of the foreign key's column pairs. |
| */ |
| int getColumnPairsSize(); |
| |
| /** |
| * Return the foreign key's single column pair. Throw an |
| * {@link IllegalStateException} if the foreign key has more than one column pair. |
| */ |
| ColumnPair getColumnPair(); |
| |
| /** |
| * Return the foreign key's <em>base</em> columns. |
| */ |
| Iterable<Column> getBaseColumns(); |
| |
| /** |
| * Return the foreign key's <em>base</em> columns that are not part of the base |
| * table's primary key. (The non-primary key base columns are not used to |
| * generate basic attributes during entity generation.) |
| */ |
| Iterable<Column> getNonPrimaryKeyBaseColumns(); |
| |
| /** |
| * Return the foreign key's <em>referenced</em> columns. |
| */ |
| Iterable<Column> getReferencedColumns(); |
| |
| /** |
| * Return whether the foreign key references the primary key of the |
| * <em>referenced</em> table and that primary key has only a single column. |
| * This can be used when determining JPA defaults. |
| */ |
| boolean referencesSingleColumnPrimaryKey(); |
| |
| |
| // ********** JPA support ********** |
| |
| /** |
| * Return an appropriate name for an attribute that holds the entity |
| * mapped to the foreign key's <em>referenced</em> table. |
| */ |
| String getAttributeName(); |
| |
| /** |
| * If the name of the <em>base</em> column adheres to the JPA spec for a |
| * default mapping (i.e. it ends with an underscore followed by the name |
| * of the <em>referenced</em> column, and the <em>referenced</em> column is the single |
| * primary key column of the <em>referenced</em> table), return the corresponding |
| * default attribute name:<pre> |
| * ForeignKey(EMP.CUBICLE_ID => CUBICLE.ID) => "CUBICLE" |
| * </pre> |
| * Return <code>null</code> if it does not adhere to the JPA spec:<pre> |
| * ForeignKey(EMP.CUBICLE_ID => CUBICLE.CUBICLE_ID) => null |
| * ForeignKey(EMP.CUBICLE => CUBICLE.ID) => null |
| * </pre> |
| */ |
| String getDefaultAttributeName(); |
| |
| /** |
| * Given the name of an attribute (field or property) that is mapped to the |
| * foreign key, build and return a string to be used as the value for the |
| * attribute's <code>@javax.persistence.JoinColumn</code> annotation's |
| * <code>name</code> element. Return <code>null</code> if the attribute |
| * maps to the join column by default. |
| * <p> |
| * Precondition: The foreign key consists of a single column pair whose |
| * referenced column is the single-column primary key of the foreign |
| * key's referenced table. |
| * <p> |
| * This is used by the entity generation code to determine whether |
| * a generated annotation must explicitly identify the join column |
| * or the calculated default adequately identifies the join column |
| * (taking into consideration case-sensitivity, special characters, etc.). |
| */ |
| String getJoinColumnAnnotationIdentifier(String attributeName); |
| |
| |
| // ********** column pair interface ********** |
| |
| /** |
| * Pair up the foreign key's column pairs, matching each <em>base</em> column with |
| * the appropriate <em>referenced</em> column. |
| * @see #getColumnPairs() |
| */ |
| interface ColumnPair { |
| |
| /** |
| * Return the column pair's <em>base</em> column. |
| */ |
| Column getBaseColumn(); |
| |
| /** |
| * Return the column pair's <em>referenced</em> column. |
| */ |
| Column getReferencedColumn(); |
| |
| Comparator<ColumnPair> BASE_COLUMN_COMPARATOR = |
| new Comparator<ColumnPair>() { |
| public int compare(ColumnPair cp1, ColumnPair cp2) { |
| return Collator.getInstance().compare(cp1.getBaseColumn().getName(), cp2.getBaseColumn().getName()); |
| } |
| @Override |
| public String toString() { |
| return "ForeignKey.ColumnPair.BASE_COLUMN_COMPARATOR"; //$NON-NLS-1$ |
| } |
| }; |
| } |
| } |