google-nomulus/java/google/registry/mapreduce/inputs/EppResourceEntityReader.java
Justine Tunney 5012893c1d mv com/google/domain/registry google/registry
This change renames directories in preparation for the great package
rename. The repository is now in a broken state because the code
itself hasn't been updated. However this should ensure that git
correctly preserves history for each file.
2016-05-13 18:55:08 -04:00

78 lines
2.9 KiB
Java

// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
//
// 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.
package com.google.domain.registry.mapreduce.inputs;
import com.google.appengine.tools.mapreduce.InputReader;
import com.google.common.collect.ImmutableSet;
import com.google.domain.registry.model.EppResource;
import com.google.domain.registry.model.index.EppResourceIndex;
import com.google.domain.registry.model.index.EppResourceIndexBucket;
import com.googlecode.objectify.Key;
import com.googlecode.objectify.Ref;
import java.util.NoSuchElementException;
/** Reader that maps over {@link EppResourceIndex} and returns resources. */
class EppResourceEntityReader<R extends EppResource> extends EppResourceBaseReader<R> {
private static final long serialVersionUID = -8042933349899971801L;
/**
* The resource classes to postfilter for.
*
* <p>This can be {@link EppResource} or any descendant classes, regardless of whether those
* classes map directly to a kind in datastore, with the restriction that none of the classes
* is a supertype of any of the others.
*/
private final ImmutableSet<Class<? extends R>> resourceClasses;
public EppResourceEntityReader(
Key<EppResourceIndexBucket> bucketKey,
ImmutableSet<Class<? extends R>> resourceClasses) {
super(
bucketKey,
ONE_MB * 2, // Estimate 2MB of memory for this reader, since it loads a (max 1MB) entity.
varargsToKinds(resourceClasses));
this.resourceClasses = resourceClasses;
}
/**
* Called for each map invocation.
*
* @throws NoSuchElementException if there are no more elements, as specified in the
* {@link InputReader#next} Javadoc.
*/
@Override
public R next() throws NoSuchElementException {
// Loop until we find a value, or nextRef() throws a NoSuchElementException.
while (true) {
Ref<? extends EppResource> reference = nextEri().getReference();
EppResource resource = reference.get();
if (resource == null) {
logger.severefmt("Broken ERI reference: %s", reference.getKey());
continue;
}
// Postfilter to distinguish polymorphic types (e.g. DomainBase and DomainResource).
for (Class<? extends R> resourceClass : resourceClasses) {
if (resourceClass.isAssignableFrom(resource.getClass())) {
@SuppressWarnings("unchecked")
R r = (R) resource;
return r;
}
}
}
}
}