001/* 002 * Copyright (c) 2016-2017 Chris K Wensel <chris@wensel.net>. All Rights Reserved. 003 * Copyright (c) 2007-2017 Xplenty, Inc. All Rights Reserved. 004 * 005 * Project and contact information: http://www.cascading.org/ 006 * 007 * This file is part of the Cascading project. 008 * 009 * Licensed under the Apache License, Version 2.0 (the "License"); 010 * you may not use this file except in compliance with the License. 011 * You may obtain a copy of the License at 012 * 013 * http://www.apache.org/licenses/LICENSE-2.0 014 * 015 * Unless required by applicable law or agreed to in writing, software 016 * distributed under the License is distributed on an "AS IS" BASIS, 017 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 018 * See the License for the specific language governing permissions and 019 * limitations under the License. 020 */ 021 022package cascading.stats; 023 024import java.util.Collection; 025 026/** 027 * 028 */ 029public interface ProvidesCounters 030 { 031 /** 032 * Method getLastSuccessfulCounterFetchTime returns the time, in millis, the last moment counters 033 * were successfully retrieved. 034 * <p> 035 * If -1, counter values were never successfully retrieved. 036 * <p> 037 * If this return value is less than the {@link CascadingStats#getFinishedTime()} it is likely the 038 * counter service became unavailable. 039 * 040 * @return the moment counters were last successfully retrieved 041 */ 042 long getLastSuccessfulCounterFetchTime(); 043 044 /** 045 * Method getCounterGroups returns all the available counter group names. 046 * 047 * @return the counterGroups (type Collection) of this CascadingStats object. 048 */ 049 Collection<String> getCounterGroups(); 050 051 /** 052 * Method getCountersFor returns all the counter names for the give group name. 053 * 054 * @param group 055 * @return Collection 056 */ 057 Collection<String> getCountersFor( String group ); 058 059 /** 060 * Method getCountersFor returns all the counter names for the counter Enum. 061 * 062 * @param group 063 * @return Collection 064 */ 065 Collection<String> getCountersFor( Class<? extends Enum> group ); 066 067 /** 068 * Method getCounter returns the current value for the given counter Enum. 069 * 070 * @param counter of type Enum 071 * @return the current counter value 072 */ 073 long getCounterValue( Enum counter ); 074 075 /** 076 * Method getCounter returns the current value for the given group and counter. 077 * 078 * @param group of type String 079 * @param counter of type String 080 * @return the current counter value 081 */ 082 long getCounterValue( String group, String counter ); 083 }