package io.ebeaninternal.api;
import io.ebean.EbeanServer;
import io.ebean.bean.BeanCollection;
import io.ebean.bean.EntityBean;
import io.ebean.util.StringHelper;
import io.ebeaninternal.server.core.OrmQueryRequest;
import io.ebeaninternal.server.deploy.BeanDescriptor;
import io.ebeaninternal.server.deploy.BeanPropertyAssocMany;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.ArrayList;
import java.util.List;
/**
* Request for loading Associated Many Beans.
*/
public class LoadManyRequest extends LoadRequest {
private static final Logger logger = LoggerFactory.getLogger(LoadManyRequest.class);
private final List<BeanCollection<?>> batch;
private final LoadManyBuffer loadContext;
private final boolean onlyIds;
private final boolean loadCache;
/**
* Construct for lazy loading.
*/
public LoadManyRequest(LoadManyBuffer loadContext, boolean onlyIds, boolean loadCache) {
this(loadContext, null, true, onlyIds, loadCache);
}
/**
* Construct for secondary query.
*/
public LoadManyRequest(LoadManyBuffer loadContext, OrmQueryRequest<?> parentRequest) {
this(loadContext, parentRequest, false, false, false);
}
private LoadManyRequest(LoadManyBuffer loadContext, OrmQueryRequest<?> parentRequest, boolean lazy, boolean onlyIds, boolean loadCache) {
super(parentRequest, lazy);
this.loadContext = loadContext;
this.batch = loadContext.getBatch();
this.onlyIds = onlyIds;
this.loadCache = loadCache;
}
@Override
public Class<?> getBeanType() {
return loadContext.getBeanDescriptor().getBeanType();
}
public String getDescription() {
return "path:" + loadContext.getFullPath() + " size:" + batch.size();
}
/**
* Return the batch of collections to actually load.
*/
public List<BeanCollection<?>> getBatch() {
return batch;
}
/**
* Return the load context.
*/
public LoadManyBuffer getLoadContext() {
return loadContext;
}
/**
* Return true if lazy loading should only load the id values.
* <p>
* This for use when lazy loading is invoked on methods such as clear() and removeAll() where it
* generally makes sense to only fetch the Id values as the other property information is not
* used.
* </p>
*/
public boolean isOnlyIds() {
return onlyIds;
}
/**
* Return true if we should load the Collection ids into the cache.
*/
public boolean isLoadCache() {
return loadCache;
}
/**
* Return the batch size used for this load context.
*/
public int getBatchSize() {
return loadContext.getBatchSize();
}
private List<Object> getParentIdList(int batchSize) {
ArrayList<Object> idList = new ArrayList<>(batchSize);
BeanPropertyAssocMany<?> many = getMany();
for (BeanCollection<?> bc : batch) {
idList.add(many.getParentId(bc.getOwnerBean()));
}
int extraIds = batchSize - batch.size();
if (extraIds > 0) {
Object firstId = idList.get(0);
for (int i = 0; i < extraIds; i++) {
idList.add(firstId);
}
}
return idList;
}
private BeanPropertyAssocMany<?> getMany() {
return loadContext.getBeanProperty();
}
public SpiQuery<?> createQuery(EbeanServer server, int batchSize) {
BeanPropertyAssocMany<?> many = getMany();
SpiQuery<?> query = (SpiQuery<?>) server.createQuery(many.getTargetType());
String orderBy = many.getLazyFetchOrderBy();
if (orderBy != null) {
query.orderBy(orderBy);
}
String extraWhere = many.getExtraWhere();
if (extraWhere != null) {
// replace special ${ta} placeholder with the base table alias
// which is always t0 and add the extra where clause
String ew = StringHelper.replaceString(extraWhere, "${ta}", "t0");
query.where().raw(ew);
}
query.setLazyLoadForParents(many);
List<Object> idList = getParentIdList(batchSize);
many.addWhereParentIdIn(query, idList, loadContext.isUseDocStore());
query.setPersistenceContext(loadContext.getPersistenceContext());
String mode = isLazy() ? "+lazy" : "+query";
query.setLoadDescription(mode, getDescription());
if (isLazy()) {
// cascade the batch size (if set) for further lazy loading
query.setLazyLoadBatchSize(getBatchSize());
}
// potentially changes the joins and selected properties
loadContext.configureQuery(query);
if (isOnlyIds()) {
// override to just select the Id values
query.select(many.getTargetIdProperty());
}
return query;
}
/**
* After the query execution check for empty collections and load L2 cache if desired.
*/
public void postLoad() {
BeanDescriptor<?> desc = loadContext.getBeanDescriptor();
BeanPropertyAssocMany<?> many = getMany();
// check for BeanCollection's that where never processed
// in the +query or +lazy load due to no rows (predicates)
for (BeanCollection<?> bc : batch) {
if (bc.checkEmptyLazyLoad()) {
if (logger.isDebugEnabled()) {
EntityBean ownerBean = bc.getOwnerBean();
Object parentId = desc.getId(ownerBean);
logger.debug("BeanCollection after lazy load was empty. type:" + ownerBean.getClass().getName() + " id:" + parentId + " owner:" + ownerBean);
}
} else if (isLoadCache()) {
Object parentId = desc.getId(bc.getOwnerBean());
desc.cacheManyPropPut(many, bc, parentId);
}
}
}
}