解决A master URL must be set in your configuration

win7 + idea + spark
对应pmo文件如下：

<properties>
        <spark.version>2.0.2</spark.version>
        <scala.version>2.11</scala.version>
    </properties>

    <dependencies>
        <!--<dependency>-->
            <!--<groupId>org.scala-lang</groupId>-->
            <!--<artifactId>scala-library</artifactId>-->
            <!--<version>2.11.8</version>-->
        <!--</dependency>-->
        <dependency>
            <groupId>org.apache.spark</groupId>
            <artifactId>spark-core_${scala.version}</artifactId>
            <version>${spark.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.spark</groupId>
            <artifactId>spark-streaming_${scala.version}</artifactId>
            <version>${spark.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.spark</groupId>
            <artifactId>spark-sql_${scala.version}</artifactId>
            <version>${spark.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.spark</groupId>
            <artifactId>spark-hive_${scala.version}</artifactId>
            <version>${spark.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.spark</groupId>
            <artifactId>spark-mllib_${scala.version}</artifactId>
            <version>${spark.version}</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.scala-tools</groupId>
                <artifactId>maven-scala-plugin</artifactId>
                <version>2.15.2</version>
                <executions>
                    <execution>
                        <id>scala-compile-first</id>
                        <goals>
                            <goal>compile</goal>
                        </goals>
                        <configuration>
                            <includes>
                                <include>**/*.scala</include>
                            </includes>
                        </configuration>
                    </execution>
                    <execution>
                        <id>scala-test-compile</id>
                        <goals>
                            <goal>testCompile</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

运行wordcount的例子时，报错：A master URL must be set in your configuration

object WordCount {
  def main(args: Array[String])
  {
    val conf = new SparkConf().setAppName("wordCount")
    val sc = new SparkContext(conf)
    val rdd = sc.textFile(args(0))
    val wordcount = rdd.flatMap(_.split(" ")).map(x => (x, 1)).reduceByKey(_ + _)
    val wordsort = wordcount.map(x => (x._2, x._1)).sortByKey(false).map(x => (x._2, x._1))
    wordsort.saveAsTextFile(args(1))
    sc.stop()
  }
}

解决办法：在VM OPTION里添加：“-Dspark.master=local”解决了：运行结果如下：