Help null pointer problem

This small example is to use spring MVC + mybatis do
login page can go jump to enter the password click submit add.do
can get as
results to the next method of finding out the data in the figure NULL


paste the following configuration file in the sql


pursuing big God pointing a brother grateful

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I think certainly where is a small problem
landlord tuning to be patient now , one step at a time
find the location of a null pointer exception
refuel
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someone did , Jiqiu
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If there is no empty database query to the username illustrate the records , there may be data does not exist Yeah !
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I do not preach what the past is an entity ~ ~ ~
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is this method error, I suspect that the sql problems, never used mybatis

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1. root mybatis okay, the front page of the data in the struts are not, how a relationship with mybatis
In addition, if an object is passed in the form of words
1.struts member variable in the object name Obj, has set get methods ( another non-standard naming may take less than the value of the struts cause problems with naming hump )
2. Properties page written Obj.xxx corresponding input box
3. object property name to see if there is no mistake
If you guarantee that you did something wrong , you should not mistake
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you put the whole code Tieshanglai
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useless struts, just springmvc write
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learn JAVA sure to locate the abnormal location ! !
null pointer is the most common but also the best handling exceptions.

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breakpoint debugging
played the console to get the database sql statement execute it and see
look at your code is not a problem , the best overall code stickers out
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entity class

mapper:

mapper.xml

serviceImp

controller

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you see the console print out the sql statement is what ? ? ?
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how print ... never used mybatis,
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breakpoint debugging , the console will sql statement
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break point for program tracing . Look in the end is which object is empty. . Very easy to solve.
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If you do not add this , myBatis I am also a long time useless, should be able to see the sql statement

  01.<?xml version="1.0" encoding="UTF-8" ?>  
  02.<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">  
  03.  
  04.<log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">  
  05.  
  06.    <!-- Console output -->  
  07.  
  08.    <appender name="STDOUT" class="org.apache.log4j.ConsoleAppender">  
  09.        <layout class="org.apache.log4j.PatternLayout">  
  10.            <param name="ConversionPattern" value="%-5p %d{MM-dd HH:mm:ss} %m  (%F:%L) \n" />  
  11.        </layout>  
  12.    </appender>  
  13.  
  14.    <category name="java.sql">  
  15.        <priority value="debug" />  
  16.    </category>  
  17.    <category name="com.ibatis">  
  18.        <priority value="debug" />  
  19.    </category>  
  20.    <root>  
  21.        <priority value="error" />  
  22.        <appender-ref ref="STDOUT" />  
  23.    </root>  
  24.  
  25.</log4j:configuration>  
  log4j.xml 添加 
  

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seems no execute sql., ...
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sql statement before the sentence is being given no output , it may not perform
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you have Definition mapped SQL statement that ah. If you do not define how to know where to find them MyBatis language
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dying, or fix, the mapping statement some
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account there anything? Before calling sq break out
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and look Huashan arrows
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can print out some I see in the console

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finally good Thank you for your help,
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hey finally get a good few hours Thank you
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Where are you wrong ? ? ? ?