hadoop---程序遇到的问题

一 程序报空指针异常。

18/12/28 23:44:55 INFO mapreduce.Job: Task Id : attempt_1546059626279_0004_r_000000_0, Status : FAILED
Error: java.lang.NullPointerException
        at org.apache.hadoop.io.Text.encode(Text.java:443)
        at org.apache.hadoop.io.Text.set(Text.java:198)
        at org.apache.hadoop.io.Text.<init>(Text.java:88)
        at flowsumsort.FlowSumReduce.reduce(FlowSumReduce.java:17)   //查看该行代码
        at flowsumsort.FlowSumReduce.reduce(FlowSumReduce.java:1)
        at org.apache.hadoop.mapreduce.Reducer.run(Reducer.java:171)
        at org.apache.hadoop.mapred.ReduceTask.runNewReducer(ReduceTask.java:627)
        at org.apache.hadoop.mapred.ReduceTask.run(ReduceTask.java:389)
        at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:167)
        at java.security.AccessController.doPrivileged(Native Method)
        at javax.security.auth.Subject.doAs(Subject.java:415)
        at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1556)
        at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:162)

查看到当前行和上一行代码如下

String phonenb = flowBean.getPhoneNb();
context.write(new Text(phonenb),flowBean);

根据报错提示应为new Text（） 里面参数有问题，转而查看对于的bean文件里面phonenb变量，发现bean文件里面该参数定义出错，导致无法取值，该值一直为空，故报空指针异常。