包含hadoop / *-common.jar仍然有“ java.lang.ClassNotFoundException：org.apache.hadoop.conf.Configuration”

Question

When practicing to realize a "hadoop RPC" sample, I keep getting this error. According to previous similar questions and answers, I've checked the jar file in my classpath and got hadoop common.jar It shows that the jar file in the classpath contains hadoop.conf.Configuration.class. And here's the code to build RPCServer:

*package rpc;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.ipc.RPC;
import org.apache.hadoop.ipc.Server;
public class RPCServer implements MyBizable {
     public String doSomething(String str) {
        return str;
    }
      public static void main(String[] args) throws  Exception {
        Server server = new RPC.Builder(new Configuration())        
        .setProtocol(MyBizable.class)
        .setInstance(new RPCServer())
        .setBindAddress("***.***.***.***")
        .setPort(****)
        .build();
        server.start();
    }
}*

And still this error shows up, anyone knows how to solve it? Any help will be greatly appreciated! THX in advance!

Answer 1

Are you using Maven ? if yes then add below dependencies.

<dependency>
    <groupId>org.apache.hadoop</groupId>
    <artifactId>hadoop-client</artifactId>
    <version>${hadoop.version}</version>
    <scope>provided</scope>
</dependency>
<dependency>
    <groupId>org.apache.hadoop</groupId>
    <artifactId>hadoop-common</artifactId>
    <version>${hadoop.version}</version>
    <scope>provided</scope>
</dependency>