package com.googlecode.objectify.impl;
import com.google.appengine.api.datastore.AsyncDatastoreService;
import com.google.appengine.api.datastore.DatastoreServiceConfig;
import com.google.appengine.api.datastore.ReadPolicy;
import com.google.appengine.api.datastore.ReadPolicy.Consistency;
import com.googlecode.objectify.Key;
import com.googlecode.objectify.Objectify;
import com.googlecode.objectify.ObjectifyFactory;
import com.googlecode.objectify.TxnType;
import com.googlecode.objectify.Work;
import com.googlecode.objectify.annotation.Entity;
import com.googlecode.objectify.cmd.Deferred;
import com.googlecode.objectify.cmd.Deleter;
import com.googlecode.objectify.cmd.Loader;
import com.googlecode.objectify.cmd.Saver;
import com.googlecode.objectify.impl.translate.CreateContext;
import com.googlecode.objectify.impl.translate.SaveContext;
import com.googlecode.objectify.impl.translate.Translator;
import com.googlecode.objectify.impl.translate.TypeKey;
import java.lang.reflect.Array;
import java.util.ArrayList;
import java.util.List;
/**
* <p>Implementation of the Objectify interface. This is also suitable for subclassing; you
* can return your own subclass by overriding ObjectifyFactory.begin().</p>
*
* <p>Note we *always* use the AsyncDatastoreService
* methods that use transactions to avoid the confusion of implicit transactions.</p>
*
* @author Jeff Schnitzer <jeff@infohazard.org>
*/
public class ObjectifyImpl<O extends Objectify> implements Objectify, Cloneable
{
/** The factory that produced us */
protected ObjectifyFactory factory;
/** Our options */
protected boolean cache = true;
protected Consistency consistency = Consistency.STRONG;
protected Double deadline;
/** */
protected Transactor<O> transactor = new TransactorNo<>(this);
/**
*/
public ObjectifyImpl(ObjectifyFactory fact) {
this.factory = fact;
}
/** Copy constructor */
public ObjectifyImpl(ObjectifyImpl<O> other) {
this.factory = other.factory;
this.cache = other.cache;
this.consistency = other.consistency;
this.deadline = other.deadline;
this.transactor = other.transactor;
}
/* (non-Javadoc)
* @see com.googlecode.objectify.Objectify#getFactory()
*/
public ObjectifyFactory factory() {
return this.factory;
}
/* (non-Javadoc)
* @see com.googlecode.objectify.Objectify#find()
*/
@Override
public Loader load() {
return new LoaderImpl<>(this);
}
/* (non-Javadoc)
* @see com.googlecode.objectify.Objectify#put()
*/
@Override
public Saver save() {
return new SaverImpl(this);
}
/* (non-Javadoc)
* @see com.googlecode.objectify.Objectify#delete()
*/
@Override
public Deleter delete() {
return new DeleterImpl(this);
}
/* (non-Javadoc)
* @see com.googlecode.objectify.Objectify#defer()
*/
@Override
public Deferred defer() {
return new DeferredImpl(this);
}
/* (non-Javadoc)
* @see com.googlecode.objectify.Objectify#consistency(com.google.appengine.api.datastore.ReadPolicy.Consistency)
*/
@Override
@SuppressWarnings("unchecked")
public O consistency(Consistency value) {
if (value == null)
throw new IllegalArgumentException("Consistency cannot be null");
ObjectifyImpl<O> clone = this.clone();
clone.consistency = value;
return (O)clone;
}
/* (non-Javadoc)
* @see com.googlecode.objectify.Objectify#deadline(java.lang.Double)
*/
@Override
@SuppressWarnings("unchecked")
public O deadline(Double value) {
ObjectifyImpl<O> clone = this.clone();
clone.deadline = value;
return (O)clone;
}
/* (non-Javadoc)
* @see com.googlecode.objectify.Objectify#cache(boolean)
*/
@Override
@SuppressWarnings("unchecked")
public O cache(boolean value) {
ObjectifyImpl<O> clone = this.clone();
clone.cache = value;
return (O)clone;
}
/* (non-Javadoc)
* @see com.googlecode.objectify.Objectify#transactionless()
*/
@Override
@SuppressWarnings("unchecked")
public O transactionless() {
return (O)transactor.transactionless(this);
}
/* (non-Javadoc)
* @see java.lang.Object#clone()
*/
@SuppressWarnings("unchecked")
protected ObjectifyImpl<O> clone() {
try {
return (ObjectifyImpl<O>)super.clone();
} catch (CloneNotSupportedException e) {
throw new RuntimeException(e); // impossible
}
}
/* (non-Javadoc)
* @see com.googlecode.objectify.Objectify#getTxn()
*/
public TransactionImpl getTransaction() {
return transactor.getTransaction();
}
/* (non-Javadoc)
* @see com.googlecode.objectify.Objectify#execute(com.googlecode.objectify.TxnType, com.googlecode.objectify.Work)
*/
@Override
public <R> R execute(TxnType txnType, Work<R> work) {
return transactor.execute(this, txnType, work);
}
/* (non-Javadoc)
* @see com.googlecode.objectify.Objectify#transact(com.googlecode.objectify.Work)
*/
@Override
public <R> R transact(Work<R> work) {
return transactor.transact(this, work);
}
/* (non-Javadoc)
* @see com.googlecode.objectify.Objectify#transact(com.googlecode.objectify.Work)
*/
@Override
public <R> R transactNew(Work<R> work) {
return this.transactNew(Integer.MAX_VALUE, work);
}
/* (non-Javadoc)
* @see com.googlecode.objectify.Objectify#transactNew(com.googlecode.objectify.Work)
*/
@Override
public <R> R transactNew(int limitTries, Work<R> work) {
return transactor.transactNew(this, limitTries, work);
}
/* (non-Javadoc)
* @see com.googlecode.objectify.Objectify#clear()
*/
@Override
public void clear() {
transactor.getSession().clear();
}
/**
* Make a datastore service config that corresponds to our options.
*/
protected DatastoreServiceConfig createDatastoreServiceConfig() {
DatastoreServiceConfig cfg = DatastoreServiceConfig.Builder.withReadPolicy(new ReadPolicy(consistency));
if (deadline != null)
cfg.deadline(deadline);
return cfg;
}
/**
* Make a datastore service config that corresponds to our options.
*/
protected AsyncDatastoreService createAsyncDatastoreService() {
return factory.createAsyncDatastoreService(this.createDatastoreServiceConfig(), cache);
}
/**
* Use this once for one operation and then throw it away
* @return a fresh engine that handles fundamental datastore operations for saving and deleting
*/
protected WriteEngine createWriteEngine() {
return new WriteEngine(this, createAsyncDatastoreService(), transactor.getSession());
}
/**
* <p>Translates the value of a filter clause into something the datastore understands. Key<?> goes to native Key,
* entities go to native Key, java.sql.Date goes to java.util.Date, etc. It uses the same translation system
* that is used for standard entity fields, but does no checking to see if the value is appropriate for the field.</p>
*
* <p>Unrecognized types are returned as-is.</p>
*
* <p>A future version of this method might check for type validity.</p>
*
* @return whatever can be put into a filter clause.
*/
protected Object makeFilterable(Object value) {
if (value == null)
return null;
// This is really quite a dilemma. We need to convert that value into something we can filter by, but we don't
// really have a lot of information about it. We could use type information from the matched field, but there's
// no guarantee that there is a field to check - it could be a typeless query or a query on an old property value.
// The only real solution is to create a (non root!) translator on the fly. Even that is not straightforward,
// because erasure wipes out any component type information in a collection. We don't know what the collection
// contains.
//
// The answer: Check for collections explicitly. Create a separate translator for every item in the collection;
// after all, it could be a heterogeneous list. This is not especially efficient but GAE only allows a handful of
// items in a IN operation and at any rate processing will still be negligible compared to the cost of a query.
// If this is an array, make life easier by turning it into a list first. Because of primitive
// mismatching we can't trust Arrays.asList().
if (value.getClass().isArray()) {
int len = Array.getLength(value);
List<Object> asList = new ArrayList<>(len);
for (int i=0; i<len; i++)
asList.add(Array.get(value, i));
value = asList;
}
if (value instanceof Iterable) {
List<Object> result = new ArrayList<>(50); // hard limit is 30, but wth
for (Object obj: (Iterable<?>)value)
result.add(makeFilterable(obj));
return result;
} else {
// Special case entity pojos that become keys
if (value.getClass().isAnnotationPresent(Entity.class)) {
return factory().keys().getMetadataSafe(value).getRawKey(value);
} else {
// Run it through a translator
Translator<Object, Object> translator = factory().getTranslators().get(new TypeKey<>(value.getClass()), new CreateContext(factory()), Path.root());
return translator.save(value, false, new SaveContext(), Path.root());
}
}
}
/** */
protected Session getSession() {
return this.transactor.getSession();
}
/** @return true if cache is enabled */
public boolean getCache() {
return cache;
}
/* (non-Javadoc)
* @see com.googlecode.objectify.Objectify#isLoaded(com.googlecode.objectify.Key)
*/
@Override
public boolean isLoaded(Key<?> key) {
return transactor.getSession().contains(key);
}
@Override
public void flush() {
transactor.getDeferrer().flush();
}
/**
* Defer the saving of one entity. Updates the session cache with this new value.
*/
void deferSave(Object entity) {
transactor.getDeferrer().deferSave(factory().keys().keyOf(entity), entity);
}
/**
* Defer the deletion of one entity. Updates the session cache with this new value.
*/
void deferDelete(Key<?> key) {
transactor.getDeferrer().deferDelete(key);
}
}