ibatis简单例子求助。
以前没学过ibatis的，虽然知道这东西将要被淘汰，但是现在的工作环境下用的就是ibatis。所以想想还是学学吧。以前只是调用人家写好的现成的dao层的。
今天试了一个例子，报错空指针，求助。
xml文件：

执行代码：

public static void main(String[] args) {
try {
com.ibatis.sqlmap.client.SqlMapClient sqlMap = null;
String resource = "sqlmap.xml";
Reader reader = Resources.getResourceAsReader(resource);
sqlMap = SqlMapClientBuilder.buildSqlMapClient(reader);
// 显示一条记录
//getNameSpace() + "." + sqlName
//第一种方式，
List<User> list = (List<User>) sqlMap.queryForList("test/test_user.getUser","10");
System.out.println(list.get(0).getName());
//第二种方式
//User user = (User) sqlMap.queryForObject("test/test_user.getUser","10");
//System.out.println(user.getName());

} catch (Exception e) {
e.printStackTrace();
}
}


最后报错：
java.lang.NullPointerException
at com.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.endTransaction(SqlMapExecutorDelegate.java:734)
at com.ibatis.sqlmap.engine.impl.SqlMapSessionImpl.endTransaction(SqlMapSessionImpl.java:176)
at com.ibatis.sqlmap.engine.impl.SqlMapClientImpl.endTransaction(SqlMapClientImpl.java:153)
at com.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.autoEndTransaction(SqlMapExecutorDelegate.java:835)
at com.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.queryForList(SqlMapExecutorDelegate.java:574)
at com.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.queryForList(SqlMapExecutorDelegate.java:541)
at com.ibatis.sqlmap.engine.impl.SqlMapSessionImpl.queryForList(SqlMapSessionImpl.java:118)
at com.ibatis.sqlmap.engine.impl.SqlMapClientImpl.queryForList(SqlMapClientImpl.java:94)
at test.IbatisTest.main(IbatisTest.java:21)
求助!                            
[解决办法]
<select id="getUser" parameterClass="int" resultClass="user">
        SELECT id,name,descs,address
        FROM test_user
        WHERE id = #value#
    </select>
WHERE id = #value#  调查询方法的时候没有传入value 的入参哦！
[解决办法]
不好意思，没看清楚，貌似   这里的入参
 List<User> list = (List<User>) sqlMap.queryForList("test/test_user.getUser","10");
要和
<select id="getUser" parameterClass="int" resultClass="user">
        SELECT id,name,descs,address 
 
        FROM test_user
        WHERE id = #value#
    </select>
的参数名称对应
[解决办法]
Map args = new HashMap();
args.put("value", "10");
List<User> list = (List<User>) sqlMap.queryForList("test/test_user.getUser",args);


<select id="getUser" parameterClass="map" resultClass="user">
        SELECT id,name,descs,address
        FROM test_user
        WHERE id = #value#
</select>

id,name,descs,address这个值要跟user严格对应才行的！
[解决办法]
parameterClass="int"
改成parameterClass="Integer"

试一试吧
[解决办法]
引用:
parameterClass="int"
改成parameterClass="Integer"

试一试吧

不好意思加上包名
 parameterClass="java.lang.Integer"

[解决办法]


引用:
Map args = new HashMap();
args.put("value", "10");
List<User> list = (List<User>) sqlMap.queryForList("test/test_user.getUser",args);


<select id="getUser" parameterClass="map" resu……



这里说的是接收返回，就算没对应也只是接收不到值而已，
报空指针是因为 sql 里面value 没有传

 parameterClass="java.lang.Integer"  
List<User> list = (List<User>) sqlMap.queryForList("test/test_user.getUser","10");
改成List<User> list = (List<User>) sqlMap.queryForList("test/test_user.getUser",value);
自己搞个int value=10，就可以了，现在报空指针是入参的错误，
[解决办法]


<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE sqlMap PUBLIC "-//iBATIS.com//DTD sql Map 2.0//EN" "http://ibatis.apache.org/dtd/sql-map-2.dtd">
<sqlMap namespace="test/test_user">
<typeAlias alias="user" type="test.entity.User" />
<!-- Use primitive wrapper type (e.g. Integer) as parameter and allow results 
to be auto-mapped results to Person object (Java Bean) properties -->
<select id="getUser" parameterClass="int" resultClass="user">
SELECT id,name,descs,address
FROM test_user
WHERE id = #value#
</select>
        <select id="getUser" parameterClass="int" resultMap="user">
SELECT id,name,descs,address
FROM test_user
WHERE id = #value#
</select>
</sqlMap>

resultClass 改成 resultMap

[解决办法]

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE sqlMap PUBLIC "-//iBATIS.com//DTD sql Map 2.0//EN" "http://ibatis.apache.org/dtd/sql-map-2.dtd">
<sqlMap namespace="test/test_user"> 
 
<typeAlias alias="user" type="" />
<!-- Use primitive wrapper type (e.g. Integer) as parameter and allow results 
to be auto-mapped results to Person object (Java Bean) properties -->

<resultMap id="user" class="test.entity.User" >     
<result column="id" property="id" jdbcType="DOUBLE" />    
<result column="name" property="name" jdbcType="VARCHAR" />      
<result column="descs" property="descs" jdbcType="VARCHAR" />     
<result column="address" property="address" jdbcType="VARCHAR" />    
</resultMap> 


<select id="getUser" parameterClass="int" resultClass="user">
SELECT id,name,descs,address
FROM test_user
WHERE id = #value#
</select>
        <select id="getUser" parameterClass="int" resultMap="user">
SELECT id,name,descs,address
FROM test_user
WHERE id = #value#
</select>
</sqlMap>

resultClass 改成 resultMap