/*
* 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.beam.sdk.transforms.windowing;
import java.util.Collection;
import org.apache.beam.sdk.coders.Coder;
import org.joda.time.Instant;
/**
* A {@link WindowFn} that represents an invalid pipeline state.
*
* @param <W> window type
*/
public class InvalidWindows<W extends BoundedWindow> extends WindowFn<Object, W> {
private String cause;
private WindowFn<?, W> originalWindowFn;
public InvalidWindows(String cause, WindowFn<?, W> originalWindowFn) {
this.originalWindowFn = originalWindowFn;
this.cause = cause;
}
/**
* Returns the reason that this {@link WindowFn} is invalid.
*/
public String getCause() {
return cause;
}
/**
* Returns the original windowFn that this InvalidWindows replaced.
*/
public WindowFn<?, W> getOriginalWindowFn() {
return originalWindowFn;
}
@Override
public Collection<W> assignWindows(AssignContext c) {
throw new UnsupportedOperationException();
}
@Override
public void mergeWindows(MergeContext c) {
throw new UnsupportedOperationException();
}
@Override
public Coder<W> windowCoder() {
return originalWindowFn.windowCoder();
}
/**
* {@code InvalidWindows} objects with the same {@code originalWindowFn} are compatible.
*/
@Override
public boolean isCompatible(WindowFn<?, ?> other) {
return getClass() == other.getClass()
&& getOriginalWindowFn().isCompatible(
((InvalidWindows<?>) other).getOriginalWindowFn());
}
@Override
public void verifyCompatibility(WindowFn<?, ?> other) throws IncompatibleWindowException {
if (!this.isCompatible(other)) {
throw new IncompatibleWindowException(
other,
String.format(
"Only %s objects with the same originalWindowFn are compatible.",
InvalidWindows.class.getSimpleName()));
}
}
@Override
public WindowMappingFn<W> getDefaultWindowMappingFn() {
throw new UnsupportedOperationException("InvalidWindows is not allowed in side inputs");
}
@Override
public Instant getOutputTime(Instant inputTimestamp, W window) {
return inputTimestamp;
}
}