ofbiz中的数据模型

Delegator
Delegator是整个ofbiz中数据库访问的入口，具体实现是GenericDelegator类，在这个类中通过

protected ModelReader modelReader = null;
protected ModelGroupReader modelGroupReader = null;

这两个属性变量去查找在xml文件中定义的数据模型
ModelReader
通过ModelReader读取模型实体ModelEntity

protected Map<String, ModelEntity> entityCache = null;

缓存

public Map<String, ModelEntity> getEntityCache() throws GenericEntityException {
if (entityCache == null) { // don't want to block here
synchronized (ModelReader.class) {
// must check if null again as one of the blocked threads can still enter
if (entityCache == null) { // now it's safe
numEntities = 0;
numViewEntities = 0;
numFields = 0;
numRelations = 0;
numAutoRelations = 0;

entityCache = new HashMap<String, ModelEntity>();
List<ModelViewEntity> tempViewEntityList = new LinkedList<ModelViewEntity>();
List<Element> tempExtendEntityElementList = new LinkedList<Element>();

UtilTimer utilTimer = new UtilTimer();

for (ResourceHandler entityResourceHandler: entityResourceHandlers) {

// utilTimer.timerString("Before getDocument in file " + entityFileName);
Document document = null;

try {
document = entityResourceHandler.getDocument();
} catch (GenericConfigException e) {
throw new GenericEntityConfException("Error getting document from resource handler", e);
}
if (document == null) {
throw new GenericEntityConfException("Could not get document for " + entityResourceHandler.toString());
}

// utilTimer.timerString("Before getDocumentElement in " + entityResourceHandler.toString());
Element docElement = document.getDocumentElement();

if (docElement == null) {
return null;
}
docElement.normalize();
Node curChild = docElement.getFirstChild();

ModelInfo def = ModelInfo.createFromElements(ModelInfo.DEFAULT, docElement);
int i = 0;

if (curChild != null) {
utilTimer.timerString("Before start of entity loop in " + entityResourceHandler.toString());
do {
boolean isEntity = "entity".equals(curChild.getNodeName());
boolean isViewEntity = "view-entity".equals(curChild.getNodeName());
boolean isExtendEntity = "extend-entity".equals(curChild.getNodeName());

if ((isEntity || isViewEntity) && curChild.getNodeType() == Node.ELEMENT_NODE) {
i++;
ModelEntity modelEntity = buildEntity(entityResourceHandler, (Element) curChild, i, def);
// put the view entity in a list to get ready for the second pass to populate fields...
if (isViewEntity) {
tempViewEntityList.add((ModelViewEntity) modelEntity);
} else {
entityCache.put(modelEntity.getEntityName(), modelEntity);
}
} else if (isExtendEntity && curChild.getNodeType() == Node.ELEMENT_NODE) {
tempExtendEntityElementList.add((Element) curChild);
}
} while ((curChild = curChild.getNextSibling()) != null);
} else {
Debug.logWarning("No child nodes found.", module);
}
utilTimer.timerString("Finished " + entityResourceHandler.toString() + " - Total Entities: " + i + " FINISHED");
}

// all entity elements in, now go through extend-entity elements and add their stuff
for (Element extendEntityElement: tempExtendEntityElementList) {
String entityName = UtilXml.checkEmpty(extendEntityElement.getAttribute("entity-name"));
ModelEntity modelEntity = entityCache.get(entityName);
if (modelEntity == null) throw new GenericEntityConfException("Entity to extend does not exist: " + entityName);
modelEntity.addExtendEntity(this, extendEntityElement);
}

// do a pass on all of the view entities now that all of the entities have
// loaded and populate the fields
while (!tempViewEntityList.isEmpty()) {
int startSize = tempViewEntityList.size();
Iterator<ModelViewEntity> mveIt = tempViewEntityList.iterator();
TEMP_VIEW_LOOP:
while (mveIt.hasNext()) {
ModelViewEntity curViewEntity = mveIt.next();
for (ModelViewEntity.ModelMemberEntity mve: curViewEntity.getAllModelMemberEntities()) {
if (!entityCache.containsKey(mve.getEntityName())) {
continue TEMP_VIEW_LOOP;
}
}
mveIt.remove();
curViewEntity.populateFields(this);
for (ModelViewEntity.ModelMemberEntity mve: curViewEntity.getAllModelMemberEntities()) {
ModelEntity me = entityCache.get(mve.getEntityName());
me.addViewEntity(curViewEntity);
}
entityCache.put(curViewEntity.getEntityName(), curViewEntity);
}
if (tempViewEntityList.size() == startSize) {
// Oops, the remaining views reference other entities
// that can't be found, or they reference other views
// that have some reference problem.
break;
}
}
if (!tempViewEntityList.isEmpty()) {
StringBuilder sb = new StringBuilder("View entities reference non-existant members:\n");
Set<String> allViews = new HashSet<String>();
for (ModelViewEntity curViewEntity: tempViewEntityList) {
allViews.add(curViewEntity.getEntityName());
}
for (ModelViewEntity curViewEntity: tempViewEntityList) {
Set<String> perViewMissingEntities = new HashSet<String>();
Iterator<ModelViewEntity.ModelMemberEntity> mmeIt = curViewEntity.getAllModelMemberEntities().iterator();
while (mmeIt.hasNext()) {
ModelViewEntity.ModelMemberEntity mme = mmeIt.next();
String memberEntityName = mme.getEntityName();
if (!entityCache.containsKey(memberEntityName)) {
// this member is not a real entity
// check to see if it is a view
if (!allViews.contains(memberEntityName)) {
// not a view, it's a real missing entity
perViewMissingEntities.add(memberEntityName);
}
}
}
for (String perViewMissingEntity: perViewMissingEntities) {
sb.append("\t[").append(curViewEntity.getEntityName()).append("] missing member entity [").append(perViewMissingEntity).append("]\n");
}

}
throw new GenericEntityConfException(sb.toString());
}

// auto-create relationships
TreeSet<String> orderedMessages = new TreeSet<String>();
for (String curEntityName: new TreeSet<String>(this.getEntityNames())) {
ModelEntity curModelEntity = this.getModelEntity(curEntityName);
if (curModelEntity instanceof ModelViewEntity) {
// for view-entities auto-create relationships for all member-entity relationships that have all corresponding fields in the view-entity

} else {
// for entities auto-create many relationships for all type one relationships

// just in case we add a new relation to the same entity, keep in a separate list and add them at the end
List<ModelRelation> newSameEntityRelations = new LinkedList<ModelRelation>();

Iterator<ModelRelation> relationsIter = curModelEntity.getRelationsIterator();
while (relationsIter.hasNext()) {
ModelRelation modelRelation = relationsIter.next();
if (("one".equals(modelRelation.getType()) || "one-nofk".equals(modelRelation.getType())) && !modelRelation.isAutoRelation()) {
ModelEntity relatedEnt = null;
try {
relatedEnt = this.getModelEntity(modelRelation.getRelEntityName());
} catch (GenericModelException e) {
throw new GenericModelException("Error getting related entity [" + modelRelation.getRelEntityName() + "] definition from entity [" + curEntityName + "]", e);
}
if (relatedEnt != null) {
// create the new relationship even if one exists so we can show what we are looking for in the info message
// don't do relationship to the same entity, unless title is "Parent", then do a "Child" automatically
String title = modelRelation.getTitle();
if (curModelEntity.getEntityName().equals(relatedEnt.getEntityName()) && "Parent".equals(title)) {
title = "Child";
}
String description = "";
String type = "";
String relEntityName = curModelEntity.getEntityName();
String fkName = "";
ArrayList<ModelKeyMap> keyMaps = new ArrayList<ModelKeyMap>();
boolean isAutoRelation = true;
Set<String> curEntityKeyFields = new HashSet<String>();
for (ModelKeyMap curkm : modelRelation.getKeyMaps()) {
keyMaps.add(new ModelKeyMap(curkm.getRelFieldName(), curkm.getFieldName()));
curEntityKeyFields.add(curkm.getFieldName());
}
keyMaps.trimToSize();
// decide whether it should be one or many by seeing if the key map represents the complete pk of the relEntity
if (curModelEntity.containsAllPkFieldNames(curEntityKeyFields)) {
// always use one-nofk, we don't want auto-fks getting in for these automatic ones
type = "one-nofk";
// to keep it clean, remove any additional keys that aren't part of the PK
List<String> curPkFieldNames = curModelEntity.getPkFieldNames();
Iterator<ModelKeyMap> nrkmIter = keyMaps.iterator();
while (nrkmIter.hasNext()) {
ModelKeyMap nrkm =nrkmIter.next();
String checkField = nrkm.getRelFieldName();
if (!curPkFieldNames.contains(checkField)) {
nrkmIter.remove();
}
}
} else {
type= "many";
}
ModelRelation newRel = ModelRelation.create(relatedEnt, description, type, title, relEntityName, fkName, keyMaps, isAutoRelation);

ModelRelation existingRelation = relatedEnt.getRelation(title + curModelEntity.getEntityName());
if (existingRelation == null) {
numAutoRelations++;
if (curModelEntity.getEntityName().equals(relatedEnt.getEntityName())) {
newSameEntityRelations.add(newRel);
} else {
relatedEnt.addRelation(newRel);
}
} else {
if (newRel.equals(existingRelation)) {
// don't warn if the target title+entity = current title+entity
if (Debug.infoOn() && !(title + curModelEntity.getEntityName()).equals(modelRelation.getTitle() + modelRelation.getRelEntityName())) {
//String errorMsg = "Relation already exists to entity [] with title [" + targetTitle + "],from entity []";
String message = "Entity [" + relatedEnt.getPackageName() + ":" + relatedEnt.getEntityName() + "] already has identical relationship to entity [" +
curModelEntity.getEntityName() + "] title [" + title + "]; would auto-create: type [" +
newRel.getType() + "] and fields [" + newRel.keyMapString(",", "") + "]";
orderedMessages.add(message);
}
} else {
String message = "Existing relationship with the same name, but different specs found from what would be auto-created for Entity [" + relatedEnt.getEntityName() + "] and relationship to entity [" +
curModelEntity.getEntityName() + "] title [" + title + "]; would auto-create: type [" +
newRel.getType() + "] and fields [" + newRel.keyMapString(",", "") + "]";
Debug.logVerbose(message, module);
}
}
} else {
String errorMsg = "Could not find related entity ["
+ modelRelation.getRelEntityName() + "], no reverse relation added.";
Debug.logWarning(errorMsg, module);
}
}
}

if (newSameEntityRelations.size() > 0) {
for (ModelRelation newRel: newSameEntityRelations) {
curModelEntity.addRelation(newRel);
}
}
}
}
if (Debug.infoOn()) {
for (String message : orderedMessages) {
Debug.logInfo(message, module);
}
Debug.logInfo("FINISHED LOADING ENTITIES - ALL FILES; #Entities=" + numEntities + " #ViewEntities=" + numViewEntities + " #Fields=" + numFields + " #Relationships=" + numRelations + " #AutoRelationships=" + numAutoRelations, module);
}
}
}
}
return entityCache;
}

从xml配置文件中读取
ModelEntity
模型实体，所有数据库相关的操作都在这里边进行
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