package xdoclet.modules.ojb.constraints;
import xdoclet.modules.ojb.CommaListIterator;
import xdoclet.modules.ojb.model.ClassDescriptorDef;
import xdoclet.modules.ojb.model.CollectionDescriptorDef;
import xdoclet.modules.ojb.model.FieldDescriptorDef;
import xdoclet.modules.ojb.model.ModelDef;
import xdoclet.modules.ojb.model.PropertyHelper;
/* Copyright 2004-2005 The Apache Software Foundation
*
* 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.
*/
/**
* Checks constraints for collection descriptors. Note that constraints may modify the collection descriptor.
* For checks of the relationships (e.g. foreignkey) see ModelConstraints.
*
* @author <a href="mailto:tomdz@users.sourceforge.net">Thomas Dudziak (tomdz@users.sourceforge.net)</a>
*/
public class CollectionDescriptorConstraints extends FeatureDescriptorConstraints
{
/** The collection interface (this type or subtypes of it can be handled by OJB) */
private final static String JAVA_COLLECTION_INTERFACE = "java.util.Collection";
/** The interface that user-defined collection classes must implement */
private final static String MANAGEABLE_COLLECTION_INTERFACE = "org.apache.ojb.broker.ManageableCollection";
/** The interface that user-defined query customizers must implement */
private final static String QUERY_CUSTOMIZER_INTERFACE = "org.apache.ojb.broker.accesslayer.QueryCustomizer";
/**
* Checks the given collection descriptor.
*
* @param collDef The collection descriptor
* @param checkLevel The amount of checks to perform
* @exception ConstraintException If a constraint has been violated
*/
public void check(CollectionDescriptorDef collDef, String checkLevel) throws ConstraintException
{
ensureElementClassRef(collDef, checkLevel);
checkInheritedForeignkey(collDef, checkLevel);
ensureCollectionClass(collDef, checkLevel);
checkProxyPrefetchingLimit(collDef, checkLevel);
checkOrderby(collDef, checkLevel);
checkQueryCustomizer(collDef, checkLevel);
}
/**
* Ensures that the given collection descriptor has a valid element-class-ref property.
*
* @param collDef The collection descriptor
* @param checkLevel The current check level (this constraint is checked in basic and strict)
* @exception ConstraintException If element-class-ref could not be determined or is invalid
*/
private void ensureElementClassRef(CollectionDescriptorDef collDef, String checkLevel) throws ConstraintException
{
if (CHECKLEVEL_NONE.equals(checkLevel))
{
return;
}
String arrayElementClassName = collDef.getProperty(PropertyHelper.OJB_PROPERTY_ARRAY_ELEMENT_CLASS_REF);
if (!collDef.hasProperty(PropertyHelper.OJB_PROPERTY_ELEMENT_CLASS_REF))
{
if (arrayElementClassName != null)
{
// we use the array element type
collDef.setProperty(PropertyHelper.OJB_PROPERTY_ELEMENT_CLASS_REF, arrayElementClassName);
}
else
{
throw new ConstraintException("Collection "+collDef.getName()+" in class "+collDef.getOwner().getName()+" does not specify its element class");
}
}
// now checking the element type
ModelDef model = (ModelDef)collDef.getOwner().getOwner();
String elementClassName = collDef.getProperty(PropertyHelper.OJB_PROPERTY_ELEMENT_CLASS_REF);
ClassDescriptorDef elementClassDef = model.getClass(elementClassName);
if (elementClassDef == null)
{
throw new ConstraintException("Collection "+collDef.getName()+" in class "+collDef.getOwner().getName()+" references an unknown class "+elementClassName);
}
if (!elementClassDef.getBooleanProperty(PropertyHelper.OJB_PROPERTY_OJB_PERSISTENT, false))
{
throw new ConstraintException("The element class "+elementClassName+" of the collection "+collDef.getName()+" in class "+collDef.getOwner().getName()+" is not persistent");
}
if (CHECKLEVEL_STRICT.equals(checkLevel) && (arrayElementClassName != null))
{
// specified element class must be a subtype of the element type
try
{
InheritanceHelper helper = new InheritanceHelper();
if (!helper.isSameOrSubTypeOf(elementClassDef, arrayElementClassName, true))
{
throw new ConstraintException("The element class "+elementClassName+" of the collection "+collDef.getName()+" in class "+collDef.getOwner().getName()+" is not the same or a subtype of the array base type "+arrayElementClassName);
}
}
catch (ClassNotFoundException ex)
{
throw new ConstraintException("Could not find the class "+ex.getMessage()+" on the classpath while checking the collection "+collDef.getName()+" in class "+collDef.getOwner().getName());
}
}
// we're adjusting the property to use the classloader-compatible form
collDef.setProperty(PropertyHelper.OJB_PROPERTY_ELEMENT_CLASS_REF, elementClassDef.getName());
}
/**
* Checks that the foreignkey is not modified in an inherited/nested m:n collection descriptor.
*
* @param collDef The collection descriptor
* @param checkLevel The current check level (this constraint is checked in basic and strict)
*/
private void checkInheritedForeignkey(CollectionDescriptorDef collDef, String checkLevel) throws ConstraintException
{
if (CHECKLEVEL_NONE.equals(checkLevel))
{
return;
}
if (!collDef.isInherited() && !collDef.isNested())
{
return;
}
if (!collDef.hasProperty(PropertyHelper.OJB_PROPERTY_INDIRECTION_TABLE))
{
return;
}
String localFk = collDef.getProperty(PropertyHelper.OJB_PROPERTY_FOREIGNKEY);
String inheritedFk = collDef.getOriginal().getProperty(PropertyHelper.OJB_PROPERTY_FOREIGNKEY);
if (!CommaListIterator.sameLists(localFk, inheritedFk))
{
throw new ConstraintException("The foreignkey property has been changed for the m:n collection "+collDef.getName()+" in class "+collDef.getOwner().getName());
}
}
/**
* Ensures that the given collection descriptor has the collection-class property if necessary.
*
* @param collDef The collection descriptor
* @param checkLevel The current check level (this constraint is checked in basic (partly) and strict)
* @exception ConstraintException If collection-class is given for an array or if no collection-class is given but required
*/
private void ensureCollectionClass(CollectionDescriptorDef collDef, String checkLevel) throws ConstraintException
{
if (CHECKLEVEL_NONE.equals(checkLevel))
{
return;
}
if (collDef.hasProperty(PropertyHelper.OJB_PROPERTY_ARRAY_ELEMENT_CLASS_REF))
{
// an array cannot have a collection-class specified
if (collDef.hasProperty(PropertyHelper.OJB_PROPERTY_COLLECTION_CLASS))
{
throw new ConstraintException("Collection "+collDef.getName()+" in class "+collDef.getOwner().getName()+" is an array but does specify collection-class");
}
else
{
// no further processing necessary as its an array
return;
}
}
if (CHECKLEVEL_STRICT.equals(checkLevel))
{
InheritanceHelper helper = new InheritanceHelper();
ModelDef model = (ModelDef)collDef.getOwner().getOwner();
String specifiedClass = collDef.getProperty(PropertyHelper.OJB_PROPERTY_COLLECTION_CLASS);
String variableType = collDef.getProperty(PropertyHelper.OJB_PROPERTY_VARIABLE_TYPE);
try
{
if (specifiedClass != null)
{
// if we have a specified class then it has to implement the manageable collection and be a sub type of the variable type
if (!helper.isSameOrSubTypeOf(specifiedClass, variableType))
{
throw new ConstraintException("The type "+specifiedClass+" specified as collection-class of the collection "+collDef.getName()+" in class "+collDef.getOwner().getName()+" is not a sub type of the variable type "+variableType);
}
if (!helper.isSameOrSubTypeOf(specifiedClass, MANAGEABLE_COLLECTION_INTERFACE))
{
throw new ConstraintException("The type "+specifiedClass+" specified as collection-class of the collection "+collDef.getName()+" in class "+collDef.getOwner().getName()+" does not implement "+MANAGEABLE_COLLECTION_INTERFACE);
}
}
else
{
// no collection class specified so the variable type has to be a collection type
if (helper.isSameOrSubTypeOf(variableType, MANAGEABLE_COLLECTION_INTERFACE))
{
// we can specify it as a collection-class as it is an manageable collection
collDef.setProperty(PropertyHelper.OJB_PROPERTY_COLLECTION_CLASS, variableType);
}
else if (!helper.isSameOrSubTypeOf(variableType, JAVA_COLLECTION_INTERFACE))
{
throw new ConstraintException("The collection "+collDef.getName()+" in class "+collDef.getOwner().getName()+" needs the collection-class attribute as its variable type does not implement "+JAVA_COLLECTION_INTERFACE);
}
}
}
catch (ClassNotFoundException ex)
{
throw new ConstraintException("Could not find the class "+ex.getMessage()+" on the classpath while checking the collection "+collDef.getName()+" in class "+collDef.getOwner().getName());
}
}
}
/**
* Checks the orderby attribute.
*
* @param collDef The collection descriptor
* @param checkLevel The current check level (this constraint is checked in basic and strict)
* @exception ConstraintException If the value for orderby is invalid (unknown field or ordering)
*/
private void checkOrderby(CollectionDescriptorDef collDef, String checkLevel) throws ConstraintException
{
if (CHECKLEVEL_NONE.equals(checkLevel))
{
return;
}
String orderbySpec = collDef.getProperty(PropertyHelper.OJB_PROPERTY_ORDERBY);
if ((orderbySpec == null) || (orderbySpec.length() == 0))
{
return;
}
ClassDescriptorDef ownerClass = (ClassDescriptorDef)collDef.getOwner();
String elementClassName = collDef.getProperty(PropertyHelper.OJB_PROPERTY_ELEMENT_CLASS_REF).replace('$', '.');
ClassDescriptorDef elementClass = ((ModelDef)ownerClass.getOwner()).getClass(elementClassName);
FieldDescriptorDef fieldDef;
String token;
String fieldName;
String ordering;
int pos;
for (CommaListIterator it = new CommaListIterator(orderbySpec); it.hasNext();)
{
token = it.getNext();
pos = token.indexOf('=');
if (pos == -1)
{
fieldName = token;
ordering = null;
}
else
{
fieldName = token.substring(0, pos);
ordering = token.substring(pos + 1);
}
fieldDef = elementClass.getField(fieldName);
if (fieldDef == null)
{
throw new ConstraintException("The field "+fieldName+" specified in the orderby attribute of the collection "+collDef.getName()+" in class "+ownerClass.getName()+" hasn't been found in the element class "+elementClass.getName());
}
if ((ordering != null) && (ordering.length() > 0) &&
!"ASC".equals(ordering) && !"DESC".equals(ordering))
{
throw new ConstraintException("The ordering "+ordering+" specified in the orderby attribute of the collection "+collDef.getName()+" in class "+ownerClass.getName()+" is invalid");
}
}
}
/**
* Checks the query-customizer setting of the given collection descriptor.
*
* @param collDef The collection descriptor
* @param checkLevel The current check level (this constraint is only checked in strict)
* @exception ConstraintException If the constraint has been violated
*/
private void checkQueryCustomizer(CollectionDescriptorDef collDef, String checkLevel) throws ConstraintException
{
if (!CHECKLEVEL_STRICT.equals(checkLevel))
{
return;
}
String queryCustomizerName = collDef.getProperty(PropertyHelper.OJB_PROPERTY_QUERY_CUSTOMIZER);
if (queryCustomizerName == null)
{
return;
}
try
{
InheritanceHelper helper = new InheritanceHelper();
if (!helper.isSameOrSubTypeOf(queryCustomizerName, QUERY_CUSTOMIZER_INTERFACE))
{
throw new ConstraintException("The class "+queryCustomizerName+" specified as query-customizer of collection "+collDef.getName()+" in class "+collDef.getOwner().getName()+" does not implement the interface "+QUERY_CUSTOMIZER_INTERFACE);
}
}
catch (ClassNotFoundException ex)
{
throw new ConstraintException("The class "+ex.getMessage()+" specified as query-customizer of collection "+collDef.getName()+" in class "+collDef.getOwner().getName()+" was not found on the classpath");
}
}
}