运行 Spark Java 程序时出现 java.lang.NoSuchMethodError

Question

我正在尝试以下程序：

import org.apache.spark.SparkConf;
import org.apache.spark.api.java.JavaRDD;
import org.apache.spark.api.java.JavaSparkContext;
import org.apache.spark.api.java.function.Function;


public class SparkMain {
    public static void main(String[] args) {
        String logFile = "~/useful/json.json    "; // Should be some file on your system
        SparkConf conf = new SparkConf().setAppName("Simple Application").setMaster("local");
        JavaSparkContext sc = new JavaSparkContext(conf);
        JavaRDD<String> logData = sc.textFile(logFile).cache();

        long numAs = logData.filter(new Function<String, Boolean>() {
            public Boolean call(String s) { return s.contains("a"); }
        }).count();

        long numBs = logData.filter(new Function<String, Boolean>() {
            public Boolean call(String s) { return s.contains("b"); }
        }).count();

        System.out.println("Lines with a: " + numAs + ", lines with b: " + numBs);
    }
}

pom.xml 文件是：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.company</groupId>
    <artifactId>artid</artifactId>
    <version>1.0-SNAPSHOT</version>
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
        </plugins>
    </build>

    <dependencies>
        <dependency>
            <groupId>com.sparkjava</groupId>
            <artifactId>spark-core</artifactId>
            <version>2.5</version>
        </dependency>

        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-simple</artifactId>
            <version>1.7.12</version>
        </dependency>

        <dependency>
            <groupId>org.apache.hadoop</groupId>
            <artifactId>hadoop-client</artifactId>
            <version>2.2.0</version>
        </dependency>


        <dependency>
            <groupId>org.scala-lang</groupId>
            <artifactId>scala-library</artifactId>
            <version>2.11.0</version>
        </dependency>

        <dependency>
            <groupId>org.scala-lang</groupId>
            <artifactId>scala-compiler</artifactId>
            <version>2.11.0</version>
        </dependency>


        <dependency>
            <groupId>org.scala-lang</groupId>
            <artifactId>scala-reflect</artifactId>
            <version>2.11.0</version>
        </dependency>

        <dependency>
            <groupId>org.apache.spark</groupId>
            <artifactId>spark-core_2.11</artifactId>
            <version>1.6.2</version>
        </dependency>


    </dependencies>


</project>

我正在使用 intellij，当我在 main 函数上运行调试时，我收到以下错误：

Using Spark's default log4j profile: org/apache/spark/log4j-defaults.properties
SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/Users/sudeep/spark/lib/slf4j-log4j12-1.7.5.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/Users/sudeep/.m2/repository/org/slf4j/slf4j-simple/1.7.12/slf4j-simple-1.7.12.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/Users/sudeep/.m2/repository/org/slf4j/slf4j-log4j12/1.7.10/slf4j-log4j12-1.7.10.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation.
SLF4J: Actual binding is of type [org.slf4j.impl.Log4jLoggerFactory]
16/07/06 00:55:57 INFO SparkContext: Running Spark version 1.6.2
16/07/06 00:55:57 WARN NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
16/07/06 00:55:58 INFO SecurityManager: Changing view acls to: sudeep
16/07/06 00:55:58 INFO SecurityManager: Changing modify acls to: sudeep
16/07/06 00:55:58 INFO SecurityManager: SecurityManager: authentication disabled; ui acls disabled; users with view permissions: Set(sudeep); users with modify permissions: Set(sudeep)
Exception in thread "main" java.lang.NoSuchMethodError: org.apache.spark.network.util.JavaUtils.timeStringAsSec(Ljava/lang/String;)J
    at org.apache.spark.util.Utils$.timeStringAsSeconds(Utils.scala:993)
    at org.apache.spark.rpc.RpcTimeout$.apply(RpcTimeout.scala:128)
    at org.apache.spark.util.RpcUtils$.lookupRpcTimeout(RpcUtils.scala:61)
    at org.apache.spark.rpc.RpcEnv.<init>(RpcEnv.scala:69)
    at org.apache.spark.rpc.netty.NettyRpcEnv.<init>(NettyRpcEnv.scala:43)
    at org.apache.spark.rpc.netty.NettyRpcEnvFactory.create(NettyRpcEnv.scala:447)
    at org.apache.spark.rpc.RpcEnv$.create(RpcEnv.scala:53)
    at org.apache.spark.SparkEnv$.create(SparkEnv.scala:253)
    at org.apache.spark.SparkEnv$.createDriverEnv(SparkEnv.scala:193)
    at org.apache.spark.SparkContext.createSparkEnv(SparkContext.scala:288)
    at org.apache.spark.SparkContext.<init>(SparkContext.scala:457)
    at org.apache.spark.api.java.JavaSparkContext.<init>(JavaSparkContext.scala:59)
    at SparkMain.main(SparkMain.java:14)
Disconnected from the target VM, address: '127.0.0.1:51826', transport: 'socket'

Process finished with exit code 1

Answer 1

每当您在 IDE 中出现“ClassNotFound”时，您需要确认这不是 IDE 故障。通常，当 Spark 的编译版本与运行时使用的版本不同时，会发生此错误。

要测试这不是 IDE 故障，只需使用构建工具 (maven run) 运行程序即可。如果它有效，那么至少您知道您的pom 文件是正确的。如果是这种情况，那么我建议创建一个具有新依赖项的新项目。您的 IDE 可能正在使用旧版本的 Spark。