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. */ /** * An expression that generates a sequence of string values, following some distribution (Uniform, Zipfian, Sequential, etc.) */ public abstract class Generator { /** * Generate the next string in the distribution. */ public abstract String nextString(); /** * 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. */ public abstract String lastString(); }