操作HDFS报java.lang.NullPointerException

在IDEA里面编写Code，在HDFS上来创建一个目录。

 //c/s
    @Before
    public void conn() throws Exception {
        Configuration conf = new Configuration(true);
        FileSystem fs = FileSystem.get(conf);
        //FileSystem   fs = FileSystem.get(java.net.URI.create("hdfs://mycluster/"), this.conf,"god");
    }

    @Test
    public void mkdir() throws Exception {
        Path dir = new Path("/msb");
        if (fs.exists(dir)){
            fs.delete(dir,true);
        }
        fs.mkdirs(dir);
    }

java.lang.NullPointerException
	at com.msb.hadoop.hdfs.TestHDFS.mkdir(TestHDFS.java:40)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

修改为：

conf = new Configuration(true);
fs = FileSystem.get(conf);

log4j:WARN No appenders could be found for logger (org.apache.hadoop.metrics2.lib.MutableMetricsFactory).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.

Process finished with exit code 0