Flink操练（三十四）之ValueState求平均值

　　1、代码逻辑实现package day03;  import org.apache.flink.api.common.state.ValueState; import org.apache.flink.api.common.state.ValueStateDescriptor; import org.apache.flink.api.common.typeinfo.Types; import org.apache.flink.api.java.tuple.Tuple2; import org.apache.flink.configuration.Configuration; import org.apache.flink.streaming.api.datastream.DataStreamSource; import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator; import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment; import org.apache.flink.streaming.api.functions.KeyedProcessFunction; import org.apache.flink.streaming.api.functions.source.SourceFunction; import org.apache.flink.util.Collector;  import java.util.Random;  /**  * @program: Flink_learn  * @description: 状态变量  * @author: Mr.逗  * @create: 2021-09-17 15:21  **/ public class StateDemo {     public static void main(String[] args) throws Exception {         StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();         env.setParallelism(1);         DataStreamSource source = env.addSource(new SourceFunction() {             private boolean isRunning = true;             private Random random = new Random();              @Override             public void run(SourceContext ctx) throws Exception {                 while (isRunning) {                     ctx.collect(                             random.nextInt(10)                     );                     Thread.sleep(1000);                 }             }              @Override             public void cancel() {                 isRunning = false;             }         });         SingleOutputStreamOperator process = source.keyBy(v -> true)                 .process(new KeyedProcessFunction() {                     //声明一个状态变量作为累加器                     // 状态变量的可见范围是当前key                     // 状态变量是单例，只能被实例化一次                     private ValueState> valueState;                     // 保存定时器的时间戳                     private ValueState timeTs;                     @Override                     public void open(Configuration parameters) throws Exception {                         super.open(parameters);                         //实例化状态变量                         valueState = getRuntimeContext().getState(new ValueStateDescriptor>(＂sum_count＂, Types.TUPLE(Types.INT, Types.INT)));                         timeTs = getRuntimeContext().getState(new ValueStateDescriptor(＂timer＂, Types.LONG));                     }                      @Override                     public void processElement(Integer value, Context ctx, Collector out) throws Exception {                         // 当第一条数据到来时，状态变量的值为null                         // 使用.value()方法读取状态变量的值，使用.update()方法更新状态变量的值                         if (valueState.value() == null) {                             valueState.update(Tuple2.of(value, 1));                         } else {                             Tuple2 tmp = valueState.value();                             valueState.update(Tuple2.of(tmp.f0 + value, tmp.f1 + 1));                         }                          if (timeTs.value() == null) {                             long tenSecLater = ctx.timerService().currentProcessingTime() + 10 * 1000;                             ctx.timerService().registerEventTimeTimer(tenSecLater);                             timeTs.update(tenSecLater);                         }                     }                     @Override                     public void onTimer(long timestamp, OnTimerContext ctx, Collector out) throws Exception {                         super.onTimer(timestamp, ctx, out);                         if (valueState.value() != null) {                             out.collect((double) valueState.value().f0 / valueState.value().f1);                             timeTs.clear();                         }                     }                 });         process.print();         String name = StateDemo.class.getName();         env.execute(name);     } } 2、结果之展示＂C:Program FilesJavajdk1.8.0_191binjava.exe＂ ＂-javaagent:F:appIntelliJ IDEA 2019.3.3libidea_rt.jar=55777:F:appIntelliJ IDEA 2019.3.3bin＂ -Dfile.encoding=UTF-8 -classpath ＂C:Program FilesJavajdk1.8.0_191jrelibcharsets.jar;C:Program FilesJavajdk1.8.0_191jrelibdeploy.jar;C:Program FilesJavajdk1.8.0_191jrelibextaccess-bridge-64.jar;C:Program FilesJavajdk1.8.0_191jrelibextcldrdata.jar;C:Program FilesJavajdk1.8.0_191jrelibextdnsns.jar;C:Program FilesJavajdk1.8.0_191jrelibextjaccess.jar;C:Program FilesJavajdk1.8.0_191jrelibextjfxrt.jar;C:Program FilesJavajdk1.8.0_191jrelibextlocaledata.jar;C:Program FilesJavajdk1.8.0_191jrelibext ashorn.jar;C:Program FilesJavajdk1.8.0_191jrelibextsunec.jar;C:Program FilesJavajdk1.8.0_191jrelibextsunjce_provider.jar;C:Program FilesJavajdk1.8.0_191jrelibextsunmscapi.jar;C:Program FilesJavajdk1.8.0_191jrelibextsunpkcs11.jar;C:Program FilesJavajdk1.8.0_191jrelibextzipfs.jar;C:Program FilesJavajdk1.8.0_191jrelibjavaws.jar;C:Program FilesJavajdk1.8.0_191jrelibjce.jar;C:Program FilesJavajdk1.8.0_191jrelibjfr.jar;C:Program FilesJavajdk1.8.0_191jrelibjfxswt.jar;C:Program FilesJavajdk1.8.0_191jrelibjsse.jar;C:Program FilesJavajdk1.8.0_191jrelibmanagement-agent.jar;C:Program FilesJavajdk1.8.0_191jrelibplugin.jar;C:Program FilesJavajdk1.8.0_191jrelibresources.jar;C:Program FilesJavajdk1.8.0_191jrelibrt.jar;D:bigDatabigData_learnFlink_learn	argetclasses;C:UsersAdministrator.m2repositoryorgapacheflinkflink-java1.13.0flink-java-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-core1.13.0flink-core-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-annotations1.13.0flink-annotations-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-metrics-core1.13.0flink-metrics-core-1.13.0.jar;C:UsersAdministrator.m2repositorycomesotericsoftwarekryokryo2.24.0kryo-2.24.0.jar;C:UsersAdministrator.m2repositorycomesotericsoftwareminlogminlog1.2minlog-1.2.jar;C:UsersAdministrator.m2repositoryorgobjenesisobjenesis2.1objenesis-2.1.jar;C:UsersAdministrator.m2repositorycommons-collectionscommons-collections3.2.2commons-collections-3.2.2.jar;C:UsersAdministrator.m2repositoryorgapachecommonscommons-compress1.20commons-compress-1.20.jar;C:UsersAdministrator.m2repositoryorgapachecommonscommons-lang33.3.2commons-lang3-3.3.2.jar;C:UsersAdministrator.m2repositoryorgapachecommonscommons-math33.5commons-math3-3.5.jar;C:UsersAdministrator.m2repositoryorgslf4jslf4j-api1.7.15slf4j-api-1.7.15.jar;C:UsersAdministrator.m2repositorycomgooglecodefindbugsjsr3051.3.9jsr305-1.3.9.jar;C:UsersAdministrator.m2repositoryorgapacheflinkforce-shading1.13.0force-shading-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-streaming-java_2.121.13.0flink-streaming-java_2.12-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-file-sink-common1.13.0flink-file-sink-common-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-runtime_2.121.13.0flink-runtime_2.12-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-queryable-state-client-java1.13.0flink-queryable-state-client-java-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-hadoop-fs1.13.0flink-hadoop-fs-1.13.0.jar;C:UsersAdministrator.m2repositorycommons-iocommons-io2.7commons-io-2.7.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-shaded-netty4.1.49.Final-13.0flink-shaded-netty-4.1.49.Final-13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-shaded-jackson2.12.1-13.0flink-shaded-jackson-2.12.1-13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-shaded-zookeeper-33.4.14-13.0flink-shaded-zookeeper-3-3.4.14-13.0.jar;C:UsersAdministrator.m2repositoryorgjavassistjavassist3.24.0-GAjavassist-3.24.0-GA.jar;C:UsersAdministrator.m2repositorycom	ypesafeakkaakka-actor_2.122.5.21akka-actor_2.12-2.5.21.jar;C:UsersAdministrator.m2repositorycom	ypesafeconfig1.3.3config-1.3.3.jar;C:UsersAdministrator.m2repositoryorgscala-langmodulesscala-java8-compat_2.12.8.0scala-java8-compat_2.12-0.8.0.jar;C:UsersAdministrator.m2repositorycom	ypesafeakkaakka-stream_2.122.5.21akka-stream_2.12-2.5.21.jar;C:UsersAdministrator.m2repositoryorgreactivestreamsreactive-streams1.0.2reactive-streams-1.0.2.jar;C:UsersAdministrator.m2repositorycom	ypesafessl-config-core_2.12.3.7ssl-config-core_2.12-0.3.7.jar;C:UsersAdministrator.m2repositoryorgscala-langmodulesscala-parser-combinators_2.121.1.1scala-parser-combinators_2.12-1.1.1.jar;C:UsersAdministrator.m2repositorycom	ypesafeakkaakka-protobuf_2.122.5.21akka-protobuf_2.12-2.5.21.jar;C:UsersAdministrator.m2repositorycom	ypesafeakkaakka-slf4j_2.122.5.21akka-slf4j_2.12-2.5.21.jar;C:UsersAdministrator.m2repositoryorgclappergrizzled-slf4j_2.121.3.2grizzled-slf4j_2.12-1.3.2.jar;C:UsersAdministrator.m2repositorycomgithubscoptscopt_2.123.5.0scopt_2.12-3.5.0.jar;C:UsersAdministrator.m2repositoryorgxerialsnappysnappy-java1.1.8.3snappy-java-1.1.8.3.jar;C:UsersAdministrator.m2repositorycom	witterchill_2.12.7.6chill_2.12-0.7.6.jar;C:UsersAdministrator.m2repositorycom	witterchill-java.7.6chill-java-0.7.6.jar;C:UsersAdministrator.m2repositoryorglz4lz4-java1.6.0lz4-java-1.6.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-shaded-guava18.0-13.0flink-shaded-guava-18.0-13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-clients_2.121.13.0flink-clients_2.12-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-optimizer_2.121.13.0flink-optimizer_2.12-1.13.0.jar;C:UsersAdministrator.m2repositorycommons-clicommons-cli1.3.1commons-cli-1.3.1.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-table-api-java-bridge_2.121.13.0flink-table-api-java-bridge_2.12-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-table-api-java1.13.0flink-table-api-java-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-table-planner-blink_2.121.13.0flink-table-planner-blink_2.12-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-table-api-scala_2.121.13.0flink-table-api-scala_2.12-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-table-api-scala-bridge_2.121.13.0flink-table-api-scala-bridge_2.12-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-table-runtime-blink_2.121.13.0flink-table-runtime-blink_2.12-1.13.0.jar;C:UsersAdministrator.m2repositoryorgcodehausjaninojanino3.0.11janino-3.0.11.jar;C:UsersAdministrator.m2repositoryorgcodehausjaninocommons-compiler3.0.11commons-compiler-3.0.11.jar;C:UsersAdministrator.m2repositoryorgapachecalciteavaticaavatica-core1.17.0avatica-core-1.17.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-streaming-scala_2.121.13.0flink-streaming-scala_2.12-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-scala_2.121.13.0flink-scala_2.12-1.13.0.jar;C:UsersAdministrator.m2repositoryorgscala-langscala-reflect2.12.7scala-reflect-2.12.7.jar;C:UsersAdministrator.m2repositoryorgscala-langscala-library2.12.7scala-library-2.12.7.jar;C:UsersAdministrator.m2repositoryorgscala-langscala-compiler2.12.7scala-compiler-2.12.7.jar;C:UsersAdministrator.m2repositoryorgscala-langmodulesscala-xml_2.121.0.6scala-xml_2.12-1.0.6.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-table-common1.13.0flink-table-common-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-connector-files1.13.0flink-connector-files-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-shaded-asm-77.1-13.0flink-shaded-asm-7-7.1-13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-cep_2.121.13.0flink-cep_2.12-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-csv1.13.0flink-csv-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-connector-kafka_2.121.13.0flink-connector-kafka_2.12-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapachekafkakafka-clients2.4.1kafka-clients-2.4.1.jar;C:UsersAdministrator.m2repositorycomgithublubenzstd-jni1.4.3-1zstd-jni-1.4.3-1.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-connector-base1.13.0flink-connector-base-1.13.0.jar;C:UsersAdministrator.m2repositoryorgapachebahirflink-connector-redis_2.111.0flink-connector-redis_2.11-1.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-streaming-java_2.111.2.0flink-streaming-java_2.11-1.2.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-runtime_2.111.2.0flink-runtime_2.11-1.2.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-shaded-hadoop21.2.0flink-shaded-hadoop2-1.2.0.jar;C:UsersAdministrator.m2repositoryorg	ukaanixz1.0xz-1.0.jar;C:UsersAdministrator.m2repositoryxmlencxmlenc.52xmlenc-0.52.jar;C:UsersAdministrator.m2repositorycommons-codeccommons-codec1.4commons-codec-1.4.jar;C:UsersAdministrator.m2repositorycommons-netcommons-net3.1commons-net-3.1.jar;C:UsersAdministrator.m2repositoryjavaxservletservlet-api2.5servlet-api-2.5.jar;C:UsersAdministrator.m2repositoryorgmortbayjettyjetty-util6.1.26jetty-util-6.1.26.jar;C:UsersAdministrator.m2repositorycomsunjerseyjersey-core1.9jersey-core-1.9.jar;C:UsersAdministrator.m2repositorycommons-elcommons-el1.0commons-el-1.0.jar;C:UsersAdministrator.m2repositorycommons-loggingcommons-logging1.1.3commons-logging-1.1.3.jar;C:UsersAdministrator.m2repositorycomjamesmurtyutilsjava-xmlbuilder.4java-xmlbuilder-0.4.jar;C:UsersAdministrator.m2repositorycommons-langcommons-lang2.6commons-lang-2.6.jar;C:UsersAdministrator.m2repositorycommons-configurationcommons-configuration1.7commons-configuration-1.7.jar;C:UsersAdministrator.m2repositorycommons-digestercommons-digester1.8.1commons-digester-1.8.1.jar;C:UsersAdministrator.m2repositoryorgcodehausjacksonjackson-core-asl1.8.8jackson-core-asl-1.8.8.jar;C:UsersAdministrator.m2repositoryorgcodehausjacksonjackson-mapper-asl1.8.8jackson-mapper-asl-1.8.8.jar;C:UsersAdministrator.m2repositoryorgapacheavroavro1.7.7avro-1.7.7.jar;C:UsersAdministrator.m2repositorycom	houghtworksparanamerparanamer2.3paranamer-2.3.jar;C:UsersAdministrator.m2repositorycomjcraftjsch.1.42jsch-0.1.42.jar;C:UsersAdministrator.m2repositorycommons-beanutilscommons-beanutils-bean-collections1.8.3commons-beanutils-bean-collections-1.8.3.jar;C:UsersAdministrator.m2repositorycommons-daemoncommons-daemon1.0.13commons-daemon-1.0.13.jar;C:UsersAdministrator.m2repositoryjavaxxmlbindjaxb-api2.2.2jaxb-api-2.2.2.jar;C:UsersAdministrator.m2repositoryjavaxxmlstreamstax-api1.0-2stax-api-1.0-2.jar;C:UsersAdministrator.m2repositoryjavaxactivationactivation1.1activation-1.1.jar;C:UsersAdministrator.m2repositoryio etty etty-all4.0.27.Final etty-all-4.0.27.Final.jar;C:UsersAdministrator.m2repositorycomdata-artisansflakka-actor_2.112.3-customflakka-actor_2.11-2.3-custom.jar;C:UsersAdministrator.m2repositorycomdata-artisansflakka-remote_2.112.3-customflakka-remote_2.11-2.3-custom.jar;C:UsersAdministrator.m2repositoryio etty etty3.8.0.Final etty-3.8.0.Final.jar;C:UsersAdministrator.m2repositoryorguncommonsmathsuncommons-maths1.2.2auncommons-maths-1.2.2a.jar;C:UsersAdministrator.m2repositorycomdata-artisansflakka-slf4j_2.112.3-customflakka-slf4j_2.11-2.3-custom.jar;C:UsersAdministrator.m2repositoryorgclappergrizzled-slf4j_2.111.0.2grizzled-slf4j_2.11-1.0.2.jar;C:UsersAdministrator.m2repositorycomgithubscoptscopt_2.113.2.0scopt_2.11-3.2.0.jar;C:UsersAdministrator.m2repositorycomfasterxmljacksoncorejackson-core2.7.4jackson-core-2.7.4.jar;C:UsersAdministrator.m2repositorycomfasterxmljacksoncorejackson-databind2.7.4jackson-databind-2.7.4.jar;C:UsersAdministrator.m2repositorycomfasterxmljacksoncorejackson-annotations2.7.0jackson-annotations-2.7.0.jar;C:UsersAdministrator.m2repositoryorgapachezookeeperzookeeper3.4.6zookeeper-3.4.6.jar;C:UsersAdministrator.m2repositoryjlinejline.9.94jline-0.9.94.jar;C:UsersAdministrator.m2repositoryjunitjunit3.8.1junit-3.8.1.jar;C:UsersAdministrator.m2repositorycom	witterchill_2.11.7.4chill_2.11-0.7.4.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-clients_2.111.2.0flink-clients_2.11-1.2.0.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-optimizer_2.111.2.0flink-optimizer_2.11-1.2.0.jar;C:UsersAdministrator.m2repositoryorgapacheslingorg.apache.sling.commons.json2.0.6org.apache.sling.commons.json-2.0.6.jar;C:UsersAdministrator.m2repositorymysqlmysql-connector-java8.0.21mysql-connector-java-8.0.21.jar;C:UsersAdministrator.m2repositorycomgoogleprotobufprotobuf-java3.11.4protobuf-java-3.11.4.jar;C:UsersAdministrator.m2repositoryorgapacheflinkflink-connector-jdbc_2.121.13.0flink-connector-jdbc_2.12-1.13.0.jar;C:UsersAdministrator.m2repositoryorgslf4jslf4j-log4j121.7.30slf4j-log4j12-1.7.30.jar;C:UsersAdministrator.m2repositorylog4jlog4j1.2.17log4j-1.2.17.jar;C:UsersAdministrator.m2repositoryorgapachelogginglog4jlog4j-to-slf4j2.14.0log4j-to-slf4j-2.14.0.jar;C:UsersAdministrator.m2repositoryorgapachelogginglog4jlog4j-api2.14.0log4j-api-2.14.0.jar;C:UsersAdministrator.m2repositoryredisclientsjedis2.9.0jedis-2.9.0.jar;C:UsersAdministrator.m2repositoryorgapachecommonscommons-pool22.4.2commons-pool2-2.4.2.jar;C:UsersAdministrator.m2repositorycomgooglecodegsongson2.8.5gson-2.8.5.jar＂ day03.StateDemo log4j:WARN No appenders could be found for logger (org.apache.flink.api.java.ClosureCleaner). log4j:WARN Please initialize the log4j system properly. log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.