Error: java: 無法訪問org.apache.hadoop.mapred.JobConf 找不到org.apache.hadoop.mapred.JobConf的類文件

Error: java: 無法訪問org.apache.hadoop.mapred.JobConf   找不到org.apache.hadoop.mapred.JobConf的類文件

出現此異常，是缺少相關的依賴包，檢查以下四個依賴包是否添加：

hadoop-mapreduce-client-core-2.7.2.jar

hadoop-common-2.7.2.jar

hadoop-mapreduce-client-common-2.7.2.jar

hadoop-mapreduce-client-jobclient-2.7.2.jar

 解決方案：

1.添加Maven依賴項，pom.xml

<dependencies>
    <dependency>
        <groupId>org.apache.hadoop</groupId>
        <artifactId>hadoop-mapreduce-client-core</artifactId>
        <version>2.7.2</version>
    </dependency>
    <dependency>
        <groupId>org.apache.hadoop</groupId>
        <artifactId>hadoop-common</artifactId>
        <version>2.7.2</version>
    </dependency>
    <dependency>
        <groupId>org.apache.hadoop</groupId>
        <artifactId>hadoop-mapreduce-client-common</artifactId>
        <version>2.7.2</version>
    </dependency>
    <dependency>
        <groupId>org.apache.hadoop</groupId>
        <artifactId>hadoop-mapreduce-client-jobclient</artifactId>
        <version>2.7.2</version>
    </dependency>
</dependencies>

2.手動下載jar

http://mvnrepository.com，用artifactId搜索對應的jar包，下載即可。