/*
* 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.geode;
// import org.apache.geode.distributed.DistributedSystem;
// import org.apache.geode.internal.statistics.StatArchiveFormat;
// import java.io.IOException;
// import java.io.Reader;
/**
* Instances of this interface provide methods that create instances of {@link Statistics}. It can
* also be used to create instances of {@link StatisticDescriptor} and {@link StatisticsType}
* because it implements {@link StatisticsTypeFactory}.
* {@link org.apache.geode.distributed.DistributedSystem} is the only instance of this interface.
*
* <P>
*
* A <code>StatisticsFactory</code> can create a {@link StatisticDescriptor statistic} of three
* numeric types: <code>int</code>, <code>long</code>, and <code>double</code>. A statistic
* (<code>StatisticDescriptor</code>) can either be a <I>gauge</I> meaning that its value can
* increase and decrease or a <I>counter</I> meaning that its value is strictly increasing. Marking
* a statistic as a counter allows statistic display tools to properly display a statistics whose
* value "wraps around" (that is, exceeds its maximum value).
*
* <P>
* The following code is an example of how to create a type using the api. In this example the type
* has two stats whose values always increase:
*
* <pre>
StatisticsFactory f = ...;
StatisticsType t = f.createType(
"StatSampler",
"Stats on the statistic sampler.",
new StatisticDescriptor[] {
f.createIntCounter("sampleCount",
"Total number of samples taken by this sampler.",
"samples"),
f.createLongCounter("sampleTime",
"Total amount of time spent taking samples.",
"milliseconds"),
}
);
this.samplerStats = f.createStatistics(t, "statSampler");
this.sampleCountId = this.samplerStats.nameToId("sampleCount");
this.sampleTimeId = this.samplerStats.nameToId("sampleTime");
* </pre>
*
* Later on the stat ids can be used to increment the stats:
*
* <pre>
* this.samplerStats.incInt(this.sampleCountId, 1);
* this.samplerStats.incLong(this.sampleTimeId, nanosSpentWorking / 1000000);
* </pre>
* <P>
* The following is an example of how to create the same type using XML. The XML data:
*
* <pre>
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE statistics PUBLIC
"-//GemStone Systems, Inc.//GemFire Statistics Type//EN"
"http://www.gemstone.com/dtd/statisticsType.dtd">
<statistics>
<type name="StatSampler">
<description>Stats on the statistic sampler.</description>
<stat name="sampleCount" storage="int" counter="true">
<description>Total number of samples taken by this sampler.</description>
<unit>samples</unit>
</stat>
<stat name="sampleTime" storage="long" counter="true">
<description>Total amount of time spent taking samples.</description>
<unit>milliseconds</unit>
</stat>
</type>
</statistics>
* </pre>
*
* The code to create the type:
*
* <pre>
StatisticsFactory f = ...;
Reader r = new InputStreamReader("fileContainingXmlData"));
StatisticsType type = f.createTypesFromXml(r)[0];
* </pre>
* <P>
*
* @see <A href="package-summary.html#statistics">Package introduction</A>
*
*
* @since GemFire 3.0
*/
public interface StatisticsFactory extends StatisticsTypeFactory {
/**
* Creates and returns a {@link Statistics} instance of the given {@link StatisticsType type} with
* default ids.
* <p>
* The created instance may not be {@link Statistics#isAtomic atomic}.
*/
public Statistics createStatistics(StatisticsType type);
/**
* Creates and returns a {@link Statistics} instance of the given {@link StatisticsType type},
* <code>textId</code>, and with a default numeric id.
* <p>
* The created instance may not be {@link Statistics#isAtomic atomic}.
*/
public Statistics createStatistics(StatisticsType type, String textId);
/**
* Creates and returns a {@link Statistics} instance of the given {@link StatisticsType type},
* <code>textId</code>, and <code>numericId</code>.
* <p>
* The created instance may not be {@link Statistics#isAtomic atomic}.
*/
public Statistics createStatistics(StatisticsType type, String textId, long numericId);
/**
* Creates and returns a {@link Statistics} instance of the given {@link StatisticsType type} with
* default ids.
* <p>
* The created instance will be {@link Statistics#isAtomic atomic}.
*/
public Statistics createAtomicStatistics(StatisticsType type);
/**
* Creates and returns a {@link Statistics} instance of the given {@link StatisticsType type},
* <code>textId</code>, and with a default numeric id.
* <p>
* The created instance will be {@link Statistics#isAtomic atomic}.
*/
public Statistics createAtomicStatistics(StatisticsType type, String textId);
/**
* Creates and returns a {@link Statistics} instance of the given {@link StatisticsType type},
* <code>textId</code>, and <code>numericId</code>.
* <p>
* The created instance will be {@link Statistics#isAtomic atomic}.
*/
public Statistics createAtomicStatistics(StatisticsType type, String textId, long numericId);
/**
* Returns an array of all the existing statistics of the given type.
*/
public Statistics[] findStatisticsByType(StatisticsType type);
/**
* Returns an array of all the existing statistics with the given textId.
*/
public Statistics[] findStatisticsByTextId(String textId);
/**
* Returns an array of all the existing statistics with the given numericId.
*/
public Statistics[] findStatisticsByNumericId(long numericId);
}