/***********************************************************************************************************************
* 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.nephele.instance;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import eu.stratosphere.core.io.IOReadableWritable;
/**
* An instance type description provides details of instance type. Is can comprise both the hardware description from
* the instance type description (as provided by the operator/administrator of the instance) as well as the actual
* hardware description which has been determined on the compute instance itself.
*
*/
public final class InstanceTypeDescription implements IOReadableWritable {
/**
* The instance type.
*/
private InstanceType instanceType = null;
/**
* The hardware description as created by the {@link InstanceManager}.
*/
private HardwareDescription hardwareDescription = null;
/**
* The maximum number of available instances of this type.
*/
private int maximumNumberOfAvailableInstances = 0;
/**
* Public default constructor required for serialization process.
*/
public InstanceTypeDescription() {
}
/**
* Constructs a new instance type description.
*
* @param instanceType
* the instance type
* @param hardwareDescription
* the hardware description as created by the {@link InstanceManager}
* @param maximumNumberOfAvailableInstances
* the maximum number of available instances of this type
*/
InstanceTypeDescription(final InstanceType instanceType, final HardwareDescription hardwareDescription,
final int maximumNumberOfAvailableInstances) {
this.instanceType = instanceType;
this.hardwareDescription = hardwareDescription;
this.maximumNumberOfAvailableInstances = maximumNumberOfAvailableInstances;
}
@Override
public void write(final DataOutput out) throws IOException {
if (this.instanceType == null) {
out.writeBoolean(false);
} else {
out.writeBoolean(true);
this.instanceType.write(out);
}
if (this.hardwareDescription == null) {
out.writeBoolean(false);
} else {
out.writeBoolean(true);
this.hardwareDescription.write(out);
}
out.writeInt(this.maximumNumberOfAvailableInstances);
}
@Override
public void read(final DataInput in) throws IOException {
if (in.readBoolean()) {
this.instanceType = new InstanceType();
this.instanceType.read(in);
} else {
this.instanceType = null;
}
if (in.readBoolean()) {
this.hardwareDescription = new HardwareDescription();
this.hardwareDescription.read(in);
}
this.maximumNumberOfAvailableInstances = in.readInt();
}
/**
* Returns the hardware description as created by the {@link InstanceManager}.
*
* @return the instance's hardware description or <code>null</code> if no description is available
*/
public HardwareDescription getHardwareDescription() {
return this.hardwareDescription;
}
/**
* Returns the instance type as determined by the {@link InstanceManager}.
*
* @return the instance type
*/
public InstanceType getInstanceType() {
return this.instanceType;
}
/**
* Returns the maximum number of instances the {@link InstanceManager} can at most allocate of this instance type
* (i.e. when no other jobs are occupying any resources).
*
* @return the maximum number of instances of this type or <code>-1</code> if the number is unknown to the
* {@link InstanceManager}
*/
public int getMaximumNumberOfAvailableInstances() {
return this.maximumNumberOfAvailableInstances;
}
}