HDFS数据访问 - TBDSUDC/tdbs-document GitHub Wiki

private static Configuration conf = new Configuration();

conf.addResource(new FileInputStream("/etc/hadoop/conf/core-site.xml"));
conf.addResource(new FileInputStream("/etc/hadoop/conf/hdfs-site.xml"));
conf.set("fs.hdfs.impl", "org.apache.hadoop.hdfs.DistributedFileSystem");

public class WebhdfsDemo {
	//日志文件
    private static Logger logger = LoggerFactory.getLogger(WebhdfsDemo.class);
    /**hadoop 相干的配置信息***/
    private static Configuration conf = new Configuration();

    // TBDS的认证信息加入
    static {
        conf.set("hadoop_security_authentication_tbds_username", "hdfs");
        conf.set("hadoop_security_authentication_tbds_secureid", "YILf620OFPXSDV15HPhonYg9ZzinB91llkNE");
        conf.set("hadoop_security_authentication_tbds_securekey", "1JsMBBMGXIQCtp69sRRNagNfLkyLoRLN");
    }

    /**
     *  HDFS配置信息注入
     */
    private static void initConfiguration(){
        try {
            conf.addResource(new FileInputStream("/etc/hadoop/conf/core-site.xml"));
            conf.addResource(new FileInputStream("/etc/hadoop/conf/hdfs-site.xml"));
            conf.set("fs.hdfs.impl", "org.apache.hadoop.hdfs.DistributedFileSystem");
        }catch (Exception e){
            logger.error("Initial component configuration fail, please check it ",e);
        }
    }

    /**运行代码**/
    public static void main(String[] args) {
        try {
            //初始化配置
            initConfiguration();
            UserGroupInformation.setConfiguration(conf);
            UserGroupInformation.loginUserFromSubject(null);
			//获取文件系统
            FileSystem fs = FileSystem.get(conf);
            
			//调用文件系统的api的方法获取文件列表信息
            FileStatus[] fileList = fs.listStatus(new Path("/"));
            //Testing for search root dir file information
            for (FileStatus fileStatus : fileList) {
                System.out.println(fileStatus.toString());
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}