package edu.brown.benchmark.ycsb.distributions;
/**
* Copyright (c) 2010 Yahoo! Inc. 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. See accompanying
* LICENSE file.
*/
/**
* A generator that is capable of generating ints as well as strings
*
* @author cooperb
*
*/
public abstract class IntegerGenerator extends Generator
{
int lastint;
/**
* Set the last value generated. IntegerGenerator subclasses must use this call
* to properly set the last string value, or the lastString() and lastInt() calls won't work.
*/
protected void setLastInt(int last)
{
lastint=last;
}
/**
* Return the next value as an int. When overriding this method, be sure to call setLastString() properly, or the lastString() call won't work.
*/
public abstract int nextInt();
/**
* Generate the next string in the distribution.
*/
public String nextString()
{
return ""+nextInt();
}
/**
* Return the previous string generated by the distribution; e.g., returned from the last nextString() call.
* Calling lastString() should not advance the distribution or have any side effects. If nextString() has not yet
* been called, lastString() should return something reasonable.
*/
@Override
public String lastString()
{
return ""+lastInt();
}
/**
* Return the previous int generated by the distribution. This call is unique to IntegerGenerator subclasses, and assumes
* IntegerGenerator subclasses always return ints for nextInt() (e.g. not arbitrary strings).
*/
public int lastInt()
{
return lastint;
}
/**
* Return the expected value (mean) of the values this generator will return.
*/
public abstract double mean();
}