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* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
****************************************************************/
package org.apache.cayenne.map;
import java.util.Iterator;
import org.apache.cayenne.CayenneRuntimeException;
import org.apache.cayenne.configuration.ConfigurationNode;
import org.apache.cayenne.configuration.ConfigurationNodeVisitor;
import org.apache.cayenne.util.CayenneMapEntry;
import org.apache.cayenne.util.Util;
import org.apache.cayenne.util.XMLEncoder;
import org.apache.commons.collections.IteratorUtils;
/**
* An ObjAttribute is a mapping descriptor of a Java class property.
*/
public class ObjAttribute extends Attribute implements ConfigurationNode {
protected String type;
protected boolean usedForLocking;
protected String dbAttributePath;
public ObjAttribute() {
}
public ObjAttribute(String name) {
super(name);
}
public ObjAttribute(String name, String type, ObjEntity entity) {
setName(name);
setType(type);
setEntity(entity);
}
/**
* Creates a clone of an ObjAttribute argument.
*
* @since 3.0
*/
public ObjAttribute(ObjAttribute attribute) {
setName(attribute.getName());
setType(attribute.getType());
setEntity(attribute.getEntity());
setDbAttributePath(attribute.getDbAttributePath());
setUsedForLocking(attribute.isUsedForLocking());
}
/**
* @since 3.1
*/
public <T> T acceptVisitor(ConfigurationNodeVisitor<T> visitor) {
return visitor.visitObjAttribute(this);
}
/**
* Returns Java class of an object property described by this attribute. Wraps any
* thrown exceptions into CayenneRuntimeException.
*/
public Class<?> getJavaClass() {
if (this.getType() == null) {
return null;
}
try {
return Util.getJavaClass(getType());
}
catch (ClassNotFoundException e) {
throw new CayenneRuntimeException("Failed to load class for name '"
+ this.getType()
+ "': "
+ e.getMessage(), e);
}
}
/**
* Prints itself as XML to the provided XMLEncoder.
*
* @since 1.1
*/
@Override
public void encodeAsXML(XMLEncoder encoder) {
encoder.print("<obj-attribute name=\"" + getName() + '\"');
if (getType() != null) {
encoder.print(" type=\"");
encoder.print(getType());
encoder.print('\"');
}
if (isUsedForLocking()) {
encoder.print(" lock=\"true\"");
}
// If this obj attribute is mapped to db attribute
if (getDbAttribute() != null
|| (((ObjEntity) getEntity()).isAbstract() && !Util
.isEmptyString(getDbAttributePath()))) {
encoder.print(" db-attribute-path=\"");
encoder.print(Util.encodeXmlAttribute(getDbAttributePath()));
encoder.print('\"');
}
encoder.println("/>");
}
/**
* Returns fully qualified Java class name of the object property represented by this
* attribute.
*/
public String getType() {
return type;
}
/**
* Sets the type of the data object property. Type is expected to be a fully qualified
* Java class name.
*/
public void setType(String type) {
this.type = type;
}
/**
* @since 3.0
*/
public boolean isPrimaryKey() {
if (dbAttributePath == null) {
return false;
}
DbAttribute dbAttribute = getDbAttribute();
return dbAttribute != null && dbAttribute.isPrimaryKey();
}
/**
* Returns whether this attribute should be used for locking.
*
* @since 1.1
*/
public boolean isUsedForLocking() {
return usedForLocking;
}
/**
* Sets whether this attribute should be used for locking.
*
* @since 1.1
*/
public void setUsedForLocking(boolean usedForLocking) {
this.usedForLocking = usedForLocking;
}
/**
* Returns a DbAttribute mapped by this ObjAttribute.
*/
public DbAttribute getDbAttribute() {
Iterator<CayenneMapEntry> pathIterator = getDbPathIterator((ObjEntity) getEntity());
CayenneMapEntry o = null;
while (pathIterator.hasNext()) {
o = pathIterator.next();
}
if (o == null) {
return getParentDbAttribute((ObjEntity) getEntity());
}
return (DbAttribute) o;
}
private DbAttribute getParentDbAttribute(ObjEntity entity) {
if (entity != null) {
ObjEntity parent = entity.getSuperEntity();
if (parent != null) {
Iterator<CayenneMapEntry> pathIterator = getDbPathIterator(parent);
CayenneMapEntry o = null;
while (pathIterator.hasNext()) {
o = pathIterator.next();
}
if (o == null) {
return getParentDbAttribute(parent);
}
return (DbAttribute) o;
}
}
return null;
}
/**
* Returns <code>true</code> if attribute inherited from a super entity.
*
* @since 3.0
*/
public boolean isInherited() {
ObjEntity owningEntity = (ObjEntity) getEntity();
if (owningEntity == null) {
return false;
}
ObjEntity superEntity = owningEntity.getSuperEntity();
if (superEntity == null) {
return false;
}
return superEntity.getAttribute(getName()) != null;
}
public Iterator<CayenneMapEntry> getDbPathIterator() {
return getDbPathIterator((ObjEntity) getEntity());
}
public Iterator<CayenneMapEntry> getDbPathIterator(ObjEntity entity) {
if (dbAttributePath == null) {
return IteratorUtils.EMPTY_ITERATOR;
}
if (entity == null) {
return IteratorUtils.EMPTY_ITERATOR;
}
DbEntity dbEnt = entity.getDbEntity();
if (dbEnt == null) {
return IteratorUtils.EMPTY_ITERATOR;
}
int lastPartStart = dbAttributePath.lastIndexOf('.');
if (lastPartStart < 0) {
DbAttribute attribute = (DbAttribute) dbEnt.getAttribute(dbAttributePath);
if (attribute == null) {
return IteratorUtils.EMPTY_ITERATOR;
}
return IteratorUtils.singletonIterator(attribute);
}
return dbEnt.resolvePathComponents(dbAttributePath);
}
/**
* Returns the the name of the mapped DbAttribute. This value is the same as
* "dbAttributePath" for regular attributes mapped to columns. It is equql to the last
* path component for the flattened attributes.
*/
public String getDbAttributeName() {
if (dbAttributePath == null) {
return null;
}
int lastDot = dbAttributePath.lastIndexOf('.');
if (lastDot < 0) {
return dbAttributePath;
}
return dbAttributePath.substring(lastDot + 1);
}
public void setDbAttributePath(String dbAttributePath) {
this.dbAttributePath = dbAttributePath;
if (isInherited()) {
((ObjEntity) entity).addAttributeOverride(getName(), dbAttributePath);
}
}
/**
* Returns a dot-separated path that starts in the root DbEntity that maps to this
* attribute's ObjEntity and spans zero or more relationships, always ending in a
* DbAttribute name.
*/
public String getDbAttributePath() {
return dbAttributePath;
}
/**
* Returns whether this attribute is "flattened", meaning that it points to a column
* from an entity other than the DbEntity mapped to the parent ObjEntity.
*
* @since 3.0
*/
public boolean isFlattened() {
return dbAttributePath != null && dbAttributePath.indexOf('.') >= 0;
}
/**
* Returns whether this attribute is mandatory
*
* @see DbAttribute#isMandatory()
*/
public boolean isMandatory() {
DbAttribute dbAttribute = getDbAttribute();
return dbAttribute == null ? false : dbAttribute.isMandatory();
}
/**
* Returns this attribute's maximum allowed length
*
* @see DbAttribute#getMaxLength()
*/
public int getMaxLength() {
DbAttribute dbAttribute = getDbAttribute();
return dbAttribute == null ? -1 : dbAttribute.getMaxLength();
}
/**
* Returns an ObjAttribute stripped of any server-side information, such as
* DbAttribute mapping.
*
* @since 1.2
*/
public ObjAttribute getClientAttribute() {
ClientObjAttribute attribute = new ClientObjAttribute(getName());
attribute.setType(getType());
DbAttribute dbAttribute = getDbAttribute();
if (dbAttribute != null) {
// expose PK attribute names - the client may need those to build ObjectIds
if (dbAttribute.isPrimaryKey()) {
attribute.setDbAttributePath(dbAttribute.getName());
attribute.setPrimaryKey(true);
}
attribute.setMandatory(isMandatory());
attribute.setMaxLength(getMaxLength());
}
// TODO: will likely need "userForLocking" property as well.
return attribute;
}
}