Server IPC version 9 cannot communicate with client version 4  hadoop hdfs连接不上 commons-httpclient-3.1.jarcommons-io-2.4.jarcommons-lang-2.6.jarcommons-logging-1.1.3.jarcommons-net-3.1.jarguava-11.0.2.jarhadoop-common-2.6.2.jarhadoop-auth-2.6.2.jarslf4j-api-1.7.5.jarhadoop-hdfs-2.6.2.jarcommons-cli-1.2.jarprotobuf-java-2.5.0.jarhtrace-core-3.0.4.jar在pom.xml中添加这些commons-httpclient-3.1.jar commons-io-2.4.jar commons-lang-2.6.jar commons-logging-1.1.3.jar commons-net-3.1.jar guava-11.0.2.jar hadoop-common-2.6.2.jar hadoop-auth-2.6.2.jar slf4j-api-1.7.5.jar hadoop-hdfs-2.6.2.jar commons-cli-1.2.jar protobuf-java-2.5.0.jar htrace-core-3.0.4.jar 以下为示例代码：  /** * @Autohor: liyj * @Description: * @Date:Created in 2017/11/7 * @Modified by : */ import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.FileStatus; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import java.io.IOException; import java.net.URI; import java.net.URISyntaxException; public class HdfsFileReader { private static final String NAME_NODE = "hdfs://tj02:8020";//nameNomeHost = localhost if you use hadoop in local mode public static void main(String[] args) throws URISyntaxException, IOException { // String fileInHdfs = "/user/hive/warehouse/t001011003"; Configuration configuration = new Configuration(); // configuration.set("fs.hdfs.impl", // org.apache.hadoop.hdfs.DistributedFileSystem.class.getName() // ); // configuration.set("fs.file.impl", // org.apache.hadoop.fs.LocalFileSystem.class.getName() // ); FileSystem fs = FileSystem.get(URI.create(NAME_NODE), configuration); // // fs.createNewFile(new Path("/user/hive/warehouse/t001011003/0000sadasd")); // String fileContent = IOUtils.toString(fs.open(new Path(fileInHdfs)), "UTF-8"); // System.out.println("File content - " + fileContent); // copyFile2Hdfs(); Path listf = new Path("/user/hive/warehouse/t001011003"); FileStatus stats[] = fs.listStatus(listf); for (int i = 0; i < stats.length; ++i) { System.out.println(stats[i].getPath().toString()); } fs.close(); } public static void copyFile2Hdfs() throws IOException { Configuration conf = new Configuration(); FileSystem hdfs = FileSystem.get(conf); //本地文件 // Path src =new Path("D:\\HebutWinOS"); //HDFS为止 Path dst = new Path("/"); // hdfs.copyFromLocalFile(src, dst); System.out.println("Upload to" + conf.get("fs.default.name")); FileStatus files[] = hdfs.listStatus(dst); for (FileStatus file : files) { System.out.println(file.getPath()); } } }