Java tutorial
/** * Copyright 2016 Netflix, Inc. * * 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. */ package com.netflix.hystrix.serial; import com.fasterxml.jackson.core.JsonGenerator; import com.netflix.hystrix.ExecutionResult; import com.netflix.hystrix.HystrixEventType; import com.netflix.hystrix.metric.HystrixRequestEvents; import java.io.IOException; import java.io.StringWriter; import java.util.List; import java.util.Map; public class SerialHystrixRequestEvents extends SerialHystrixMetric { @Deprecated public static byte[] toBytes(HystrixRequestEvents requestEvents) { throw new UnsupportedOperationException( "Not implemented anymore. Will be implemented in a new class shortly"); } public static String toJsonString(HystrixRequestEvents requestEvents) { StringWriter jsonString = new StringWriter(); try { JsonGenerator json = jsonFactory.createGenerator(jsonString); serializeRequestEvents(requestEvents, json); } catch (Exception e) { throw new RuntimeException(e); } return jsonString.getBuffer().toString(); } private static void serializeRequestEvents(HystrixRequestEvents requestEvents, JsonGenerator json) { try { json.writeStartArray(); for (Map.Entry<HystrixRequestEvents.ExecutionSignature, List<Integer>> entry : requestEvents .getExecutionsMappedToLatencies().entrySet()) { convertExecutionToJson(json, entry.getKey(), entry.getValue()); } json.writeEndArray(); json.close(); } catch (Exception e) { throw new RuntimeException(e); } } private static void convertExecutionToJson(JsonGenerator json, HystrixRequestEvents.ExecutionSignature executionSignature, List<Integer> latencies) throws IOException { json.writeStartObject(); json.writeStringField("name", executionSignature.getCommandName()); json.writeArrayFieldStart("events"); ExecutionResult.EventCounts eventCounts = executionSignature.getEventCounts(); for (HystrixEventType eventType : HystrixEventType.values()) { if (!eventType.equals(HystrixEventType.COLLAPSED)) { if (eventCounts.contains(eventType)) { int eventCount = eventCounts.getCount(eventType); if (eventCount > 1) { json.writeStartObject(); json.writeStringField("name", eventType.name()); json.writeNumberField("count", eventCount); json.writeEndObject(); } else { json.writeString(eventType.name()); } } } } json.writeEndArray(); json.writeArrayFieldStart("latencies"); for (int latency : latencies) { json.writeNumber(latency); } json.writeEndArray(); if (executionSignature.getCachedCount() > 0) { json.writeNumberField("cached", executionSignature.getCachedCount()); } if (executionSignature.getEventCounts().contains(HystrixEventType.COLLAPSED)) { json.writeObjectFieldStart("collapsed"); json.writeStringField("name", executionSignature.getCollapserKey().name()); json.writeNumberField("count", executionSignature.getCollapserBatchSize()); json.writeEndObject(); } json.writeEndObject(); } }