| /* |
| * 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.cassandra.service.reads; |
| |
| import java.util.concurrent.TimeUnit; |
| import java.util.regex.Matcher; |
| import java.util.regex.Pattern; |
| |
| import com.google.common.base.Objects; |
| |
| import com.codahale.metrics.Snapshot; |
| import org.apache.cassandra.exceptions.ConfigurationException; |
| import org.apache.cassandra.schema.TableParams; |
| |
| public class FixedSpeculativeRetryPolicy implements SpeculativeRetryPolicy |
| { |
| private static final Pattern PATTERN = Pattern.compile("^(?<val>[0-9.]+)ms$", Pattern.CASE_INSENSITIVE); |
| |
| private final int speculateAtMilliseconds; |
| |
| FixedSpeculativeRetryPolicy(int speculateAtMilliseconds) |
| { |
| this.speculateAtMilliseconds = speculateAtMilliseconds; |
| } |
| |
| @Override |
| public long calculateThreshold(Snapshot latency, long existingValue) |
| { |
| return TimeUnit.MILLISECONDS.toNanos(speculateAtMilliseconds); |
| } |
| |
| @Override |
| public Kind kind() |
| { |
| return Kind.FIXED; |
| } |
| |
| @Override |
| public boolean equals(Object obj) |
| { |
| if (!(obj instanceof FixedSpeculativeRetryPolicy)) |
| return false; |
| FixedSpeculativeRetryPolicy rhs = (FixedSpeculativeRetryPolicy) obj; |
| return speculateAtMilliseconds == rhs.speculateAtMilliseconds; |
| } |
| |
| @Override |
| public int hashCode() |
| { |
| return Objects.hashCode(kind(), speculateAtMilliseconds); |
| } |
| |
| @Override |
| public String toString() |
| { |
| return String.format("%dms", speculateAtMilliseconds); |
| } |
| |
| static FixedSpeculativeRetryPolicy fromString(String str) |
| { |
| Matcher matcher = PATTERN.matcher(str); |
| |
| if (!matcher.matches()) |
| throw new IllegalArgumentException(); |
| |
| String val = matcher.group("val"); |
| try |
| { |
| // historically we've always parsed this as double, but treated as int; so we keep doing it for compatibility |
| return new FixedSpeculativeRetryPolicy((int) Double.parseDouble(val)); |
| } |
| catch (IllegalArgumentException e) |
| { |
| throw new ConfigurationException(String.format("Invalid value %s for option '%s'", str, TableParams.Option.SPECULATIVE_RETRY)); |
| } |
| } |
| |
| static boolean stringMatches(String str) |
| { |
| return PATTERN.matcher(str).matches(); |
| } |
| } |