final class JoinColumnVisitor extends BaseTreeVisitor {
@Override
public boolean onStartNode(ProjectPath path) {
JpaRelationship relationship = (JpaRelationship) path.getObjectParent();
JpaJoinColumn column = (JpaJoinColumn) path.getObject();
if (column.getTable() == null) {
JpaEntity entity = path.firstInstanceOf(JpaEntity.class);
column.setTable(entity.getTable().getName());
}
// JPA Spec, 2.1.8.2 (same for all relationship owners):
// The following mapping defaults apply: [...]
// Table A contains a foreign key to table B. The foreign key column
// name is formed as the concatenation of the following: the name of
// the relationship property or field of entityA; "_" ; the name of
// the primary key column in table B. The foreign key column has the
// same type as the primary key of table B.
JpaEntityMap map = path.firstInstanceOf(JpaEntityMap.class);
JpaEntity target = map.entityForClass(relationship.getTargetEntityName());
if (target == null) {
context.recordConflict(new SimpleValidationFailure(
relationship,
"Invalid relationship target "
+ relationship.getTargetEntityName()));
}
else if (target.getAttributes() == null
|| target.getAttributes().getIds().isEmpty()) {
context.recordConflict(new SimpleValidationFailure(
target,
"Relationship target has no PK defined: "
+ relationship.getTargetEntityName()));
}
else if (target.getAttributes().getIds().size() > 1) {
// TODO: andrus, 4/30/2006 implement this; note that instead of
// checking for "attribute.getJoinColumns().isEmpty()" above,
// we'll have to match individual columns
context.recordConflict(new SimpleValidationFailure(
relationship,
"Defaults for compound FK are not implemented."));
}
else {
JpaId id = target.getAttributes().getIds().iterator().next();
String pkName = id.getColumn() != null ? id.getColumn().getName() : id
.getName();
column.setName(relationship.getName() + '_' + pkName);
column.setReferencedColumnName(id.getColumn() != null ? id
.getColumn()
.getName() : id.getName());
}