1.場景
在搭建好Hadoop+Spark環境后，現准備在此環境上提交簡單的任務到Spark進行計算並輸出結果。搭建過程：http://www.cnblogs.com/zengxiaoliang/p/6478859.html
本人比較熟悉Java語言，現以Java的WordCount為例講解這整個過程，要實現計算出給定文本中每個單詞出現的次數。
2.環境測試
在講解例子之前，我想先測試一下之前搭建好的環境。
2.1測試Hadoop環境
首先創建一個文件wordcount.txt 內容如下：
Hello hadoop
hello spark
hello bigdata
yellow banana
red apple
然后執行如下命令：
hadoop fs -mkdir -p /Hadoop/Input（在HDFS創建目錄）
hadoop fs -put wordcount.txt /Hadoop/Input（將wordcount.txt文件上傳到HDFS）
hadoop fs -ls /Hadoop/Input （查看上傳的文件）
hadoop fs -text /Hadoop/Input/wordcount.txt （查看文件內容）
2.2Spark環境測試
我使用spark-shell，做一個簡單的WordCount的測試。我就用上面Hadoop測試上傳到HDFS的文件wordcount.txt。
首先啟動spark-shell命令：
spark-shell
然后直接輸入scala語句：
val file=sc.textFile("hdfs://Master:9000/Hadoop/Input/wordcount.txt")
val rdd = file.flatMap(line => line.split(" ")).map(word => (word,1)).reduceByKey(_+_)
rdd.collect()
rdd.foreach(println)
退出使用如下命令：
:quit
這樣環境測試就結束了。
3.Java實現單詞計數
package com.example.spark; import java.util.Arrays; import java.util.Iterator; import java.util.List; import java.util.regex.Pattern; import org.apache.spark.SparkConf; import org.apache.spark.api.java.JavaPairRDD; import org.apache.spark.api.java.JavaRDD; import org.apache.spark.api.java.JavaSparkContext; import org.apache.spark.api.java.function.FlatMapFunction; import org.apache.spark.api.java.function.Function2; import org.apache.spark.api.java.function.PairFunction; import scala.Tuple2; public final class WordCount { private static final Pattern SPACE = Pattern.compile(" "); public static void main(String[] args) throws Exception { SparkConf conf = new SparkConf().setAppName("kevin's first spark app"); JavaSparkContext sc = new JavaSparkContext(conf); JavaRDD<String> lines = sc.textFile(args[0]).cache(); JavaRDD<String> words = lines.flatMap(new FlatMapFunction<String, String>() { private static final long serialVersionUID = 1L; @Override public Iterator<String> call(String s) { return Arrays.asList(SPACE.split(s)).iterator(); } }); JavaPairRDD<String, Integer> ones = words.mapToPair(new PairFunction<String, String, Integer>() { private static final long serialVersionUID = 1L; @Override public Tuple2<String, Integer> call(String s) { return new Tuple2<String, Integer>(s, 1); } }); JavaPairRDD<String, Integer> counts = ones.reduceByKey(new Function2<Integer, Integer, Integer>() { private static final long serialVersionUID = 1L; @Override public Integer call(Integer i1, Integer i2) { return i1 + i2; } }); List<Tuple2<String, Integer>> output = counts.collect(); for (Tuple2<?, ?> tuple : output) { System.out.println(tuple._1() + ": " + tuple._2()); } sc.close(); } }
4.任務提交實現
將上面Java實現的單詞計數打成jar包spark-example-0.0.1-SNAPSHOT.jar，並且將jar包上傳到Master節點，我是將jar包上傳到/opt目錄下，本文將以兩種方式提交任務到spark，第一種是以spark-submit命令的方式提交任務，第二種是以java web的方式提交任務。
4.1以spark-submit命令的方式提交任務
spark-submit --master spark://114.55.246.88:7077 --class com.example.spark.WordCount /opt/spark-example-0.0.1-SNAPSHOT.jar hdfs://Master:9000/Hadoop/Input/wordcount.txt
4.2以java web的方式提交任務
我是用spring boot搭建的java web框架，實現代碼如下：
1）新建maven項目spark-submit
2）pom.xml文件內容，這里要注意spark的依賴jar包要與scala的版本相對應，如spark-core_2.11，這后面2.11就是你安裝的scala的版本。
<?xml version="1.0"?> <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> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.4.1.RELEASE</version> </parent> <artifactId>spark-submit</artifactId> <description>spark-submit</description> <properties> <start-class>com.example.spark.SparkSubmitApplication</start-class> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <java.version>1.8</java.version> <commons.version>3.4</commons.version> <org.apache.spark-version>2.1.0</org.apache.spark-version> </properties> <dependencies> <dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-lang3</artifactId> <version>${commons.version}</version> </dependency> <dependency> <groupId>org.apache.tomcat.embed</groupId> <artifactId>tomcat-embed-jasper</artifactId> <scope>provided</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-redis</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>com.jayway.jsonpath</groupId> <artifactId>json-path</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> <exclusions> <exclusion> <artifactId>spring-boot-starter-tomcat</artifactId> <groupId>org.springframework.boot</groupId> </exclusion> </exclusions> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jetty</artifactId> <exclusions> <exclusion> <groupId>org.eclipse.jetty.websocket</groupId> <artifactId>*</artifactId> </exclusion> </exclusions> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jetty</artifactId> <scope>provided</scope> </dependency> <dependency> <groupId>javax.servlet</groupId> <artifactId>jstl</artifactId> </dependency> <dependency> <groupId>org.eclipse.jetty</groupId> <artifactId>apache-jsp</artifactId> <scope>provided</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-solr</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>javax.servlet</groupId> <artifactId>jstl</artifactId> </dependency> <dependency> <groupId>org.apache.spark</groupId> <artifactId>spark-core_2.11</artifactId> <version>${org.apache.spark-version}</version> </dependency> <dependency> <groupId>org.apache.spark</groupId> <artifactId>spark-sql_2.11</artifactId> <version>${org.apache.spark-version}</version> </dependency> <dependency> <groupId>org.apache.spark</groupId> <artifactId>spark-hive_2.11</artifactId> <version>${org.apache.spark-version}</version> </dependency> <dependency> <groupId>org.apache.spark</groupId> <artifactId>spark-streaming_2.11</artifactId> <version>${org.apache.spark-version}</version> </dependency> <dependency> <groupId>org.apache.hadoop</groupId> <artifactId>hadoop-client</artifactId> <version>2.7.3</version> </dependency> <dependency> <groupId>org.apache.spark</groupId> <artifactId>spark-streaming-kafka_2.11</artifactId> <version>1.6.3</version> </dependency> <dependency> <groupId>org.apache.spark</groupId> <artifactId>spark-graphx_2.11</artifactId> <version>${org.apache.spark-version}</version> </dependency> <dependency> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-assembly-plugin</artifactId> <version>3.0.0</version> </dependency> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-core</artifactId> <version>2.6.5</version> </dependency> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.6.5</version> </dependency> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-annotations</artifactId> <version>2.6.5</version> </dependency> </dependencies> <packaging>war</packaging> <repositories> <repository> <id>spring-snapshots</id> <name>Spring Snapshots</name> <url>https://repo.spring.io/snapshot</url> <snapshots> <enabled>true</enabled> </snapshots> </repository> <repository> <id>spring-milestones</id> <name>Spring Milestones</name> <url>https://repo.spring.io/milestone</url> <snapshots> <enabled>false</enabled> </snapshots> </repository> <repository> <id>maven2</id> <url>http://repo1.maven.org/maven2/</url> </repository> </repositories> <pluginRepositories> <pluginRepository> <id>spring-snapshots</id> <name>Spring Snapshots</name> <url>https://repo.spring.io/snapshot</url> <snapshots> <enabled>true</enabled> </snapshots> </pluginRepository> <pluginRepository> <id>spring-milestones</id> <name>Spring Milestones</name> <url>https://repo.spring.io/milestone</url> <snapshots> <enabled>false</enabled> </snapshots> </pluginRepository> </pluginRepositories> <build> <plugins> <plugin> <artifactId>maven-war-plugin</artifactId> <configuration> <warSourceDirectory>src/main/webapp</warSourceDirectory> </configuration> </plugin> <plugin> <groupId>org.mortbay.jetty</groupId> <artifactId>jetty-maven-plugin</artifactId> <configuration> <systemProperties> <systemProperty> <name>spring.profiles.active</name> <value>development</value> </systemProperty> <systemProperty> <name>org.eclipse.jetty.server.Request.maxFormContentSize</name> <!-- -1代表不作限制 --> <value>600000</value> </systemProperty> </systemProperties> <useTestClasspath>true</useTestClasspath> <webAppConfig> <contextPath>/</contextPath> </webAppConfig> <connectors> <connector implementation="org.eclipse.jetty.server.nio.SelectChannelConnector"> <port>7080</port> </connector> </connectors> </configuration> </plugin> </plugins> </build> </project>
3）SubmitJobToSpark.java
package com.example.spark; import org.apache.spark.deploy.SparkSubmit; /** * @author kevin * */ public class SubmitJobToSpark { public static void submitJob() { String[] args = new String[] { "--master", "spark://114.55.246.88:7077", "--name", "test java submit job to spark", "--class", "com.example.spark.WordCount", "/opt/spark-example-0.0.1-SNAPSHOT.jar", "hdfs://Master:9000/Hadoop/Input/wordcount.txt" }; SparkSubmit.main(args); } }
4）SparkController.java
package com.example.spark.web.controller; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.bind.annotation.ResponseBody; import com.example.spark.SubmitJobToSpark; @Controller @RequestMapping("spark") public class SparkController { private Logger logger = LoggerFactory.getLogger(SparkController.class); @RequestMapping(value = "sparkSubmit", method = { RequestMethod.GET, RequestMethod.POST }) @ResponseBody public String sparkSubmit(HttpServletRequest request, HttpServletResponse response) { logger.info("start submit spark tast..."); SubmitJobToSpark.submitJob(); return "hello"; } }
5）將項目spark-submit打成war包部署到Master節點tomcat上，訪問如下請求：
http://114.55.246.88:9090/spark-submit/spark/sparkSubmit
在tomcat的log中能看到計算的結果。