/***********************************************************************************************************************
* Copyright (C) 2010-2013 by the Stratosphere project (http://stratosphere.eu)
*
* 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 eu.stratosphere.compiler.dag;
/**
* Enumeration to indicate the mode of temporarily materializing the data that flows across a connection.
* Introducing such an artificial dam is sometimes necessary to avoid that a certain data flows deadlock
* themselves, or as a cache to replay an intermediate result.
*/
public enum TempMode {
NONE(false, false),
PIPELINE_BREAKER(false, true),
CACHED(true, false),
CACHING_PIPELINE_BREAKER(true, true);
// --------------------------------------------------------------------------------------------
private final boolean cached;
private final boolean breaksPipeline;
private TempMode(boolean cached, boolean breaksPipeline) {
this.cached = cached;
this.breaksPipeline = breaksPipeline;
}
public boolean isCached() {
return cached;
}
public boolean breaksPipeline() {
return breaksPipeline;
}
public TempMode makePipelineBreaker() {
if (this == NONE) {
return PIPELINE_BREAKER;
} else if (this == CACHED) {
return CACHING_PIPELINE_BREAKER;
} else {
return this;
}
}
public TempMode makeCached() {
if (this == NONE) {
return CACHED;
} else if (this == PIPELINE_BREAKER) {
return CACHING_PIPELINE_BREAKER;
} else {
return this;
}
}
}