A confusing "No enum constant" exception

MyBatis version

3.5.6

Database vendor and version

PostgreSQL 12.4 PostgreSQL Driver 42.2.19 Java 11.0.8

Test case or example project

public class Mybatis {
    public static class History {

        public enum Operation {
            FOO,
            BAR
        }

        int id;
        int userId;
        Operation operation;

        History(int id, Operation operation) {
            this.id = id;
            this.userId = id; // Just for test
            this.operation = operation;
        }
    }

    public static void main(String[] args) throws IOException {
        InputStream stream = Resources.getResourceAsStream("mybatis.xml");
        SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(stream);
        try (SqlSession session = factory.openSession()) {
            HistoryMapper mapper = session.getMapper(HistoryMapper.class);

            mapper.insert(new History(1, History.Operation.FOO));
            mapper.insert(new History(2, History.Operation.BAR));
            session.commit();

            mapper.select();
        }
    }
}

HistoryMapper.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
  "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

<mapper namespace="rockworkx.HistoryMapper">
  <select id="select" resultType="History">
    SELECT history.id, history.user_id, history.operation
    FROM history
  </select>

  <insert id="insert" parameterType="History">
    INSERT
    INTO history(id, user_id, operation)
    VALUES (#{id}, #{userId}, #{operation})
  </insert>
</mapper>

mybatis.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
  "http://mybatis.org/dtd/mybatis-3-config.dtd">

<configuration>
  <settings>
    <setting name="mapUnderscoreToCamelCase" value="true"/>
  </settings>
  <typeAliases>
    <typeAlias alias="History" type="rockworkx.Mybatis$History" />
  </typeAliases>
  <environments default="postgres">
    <environment id="postgres">
      <transactionManager type="JDBC" />
      <dataSource type="POOLED">
        <property name="driver" value="org.postgresql.Driver" />
        <property name="url" value="jdbc:postgresql://localhost:5432/postgres" />
        <property name="username" value="postgres" />
        <property name="password" value="postgres" />
      </dataSource>
    </environment>
  </environments>
  <mappers>
    <mapper resource="HistoryMapper.xml" />
  </mappers>
</configuration>

Steps to reproduce

When I use an underscored column user_id together with a java Enum type, Mybatis throws a IllegalArgumentException with message No enum constant. But if I get rid of the underscored column user_id, everything goes well. And I also confused with the exception message:

Cause: org.apache.ibatis.executor.result.ResultMapException: Error attempting to get column 'user_id' from result set.  Cause: java.lang.IllegalArgumentException: No enum constant rockworkx.Mybatis.History.Operation.1

Why the user_id column is related to the Enum type Operation ?

I guess that some implementation details dealing with underscored column or Enum type may be wrong.

Expected result

Actual result

Exception in thread "main" org.apache.ibatis.exceptions.PersistenceException: 
### Error querying database.  Cause: org.apache.ibatis.executor.result.ResultMapException: Error attempting to get column 'user_id' from result set.  Cause: java.lang.IllegalArgumentException: No enum constant rockworkx.Mybatis.History.Operation.1
### The error may exist in HistoryMapper.xml
### The error may involve rockworkx.HistoryMapper.select
### The error occurred while handling results
### SQL: SELECT history.id, history.user_id, history.operation     FROM history
### Cause: org.apache.ibatis.executor.result.ResultMapException: Error attempting to get column 'user_id' from result set.  Cause: java.lang.IllegalArgumentException: No enum constant rockworkx.Mybatis.History.Operation.1
	at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:30)
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:149)
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:140)
	at org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:147)
	at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:80)
	at org.apache.ibatis.binding.MapperProxy$PlainMethodInvoker.invoke(MapperProxy.java:152)
	at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:85)
	at com.sun.proxy.$Proxy4.select(Unknown Source)
	at rockworkx.Mybatis.main(Mybatis.java:40)
Caused by: org.apache.ibatis.executor.result.ResultMapException: Error attempting to get column 'user_id' from result set.  Cause: java.lang.IllegalArgumentException: No enum constant rockworkx.Mybatis.History.Operation.1
	at org.apache.ibatis.type.BaseTypeHandler.getResult(BaseTypeHandler.java:87)
	at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.createUsingConstructor(DefaultResultSetHandler.java:710)
	at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.createByConstructorSignature(DefaultResultSetHandler.java:693)
	at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.createResultObject(DefaultResultSetHandler.java:657)
	at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.createResultObject(DefaultResultSetHandler.java:630)
	at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.getRowValue(DefaultResultSetHandler.java:397)
	at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleRowValuesForSimpleResultMap(DefaultResultSetHandler.java:354)
	at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleRowValues(DefaultResultSetHandler.java:328)
	at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleResultSet(DefaultResultSetHandler.java:301)
	at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleResultSets(DefaultResultSetHandler.java:194)
	at org.apache.ibatis.executor.statement.PreparedStatementHandler.query(PreparedStatementHandler.java:65)
	at org.apache.ibatis.executor.statement.RoutingStatementHandler.query(RoutingStatementHandler.java:79)
	at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:63)
	at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:325)
	at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156)
	at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109)
	at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:89)
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:147)
	... 7 more
Caused by: java.lang.IllegalArgumentException: No enum constant rockworkx.Mybatis.History.Operation.1
	at java.base/java.lang.Enum.valueOf(Enum.java:240)
	at org.apache.ibatis.type.EnumTypeHandler.getNullableResult(EnumTypeHandler.java:49)
	at org.apache.ibatis.type.EnumTypeHandler.getNullableResult(EnumTypeHandler.java:26)
	at org.apache.ibatis.type.BaseTypeHandler.getResult(BaseTypeHandler.java:85)
	... 24 more

[harawata]

@shenc ,

Because the constructor takes two arguments int and Operation and the second columns in the result set is user_id. Any of the following could be a solution:

• Change the order of the columns.
• Declare default (i.e. no-arg) constructor.
• Use <resultMap /> with <constructor /> instead of relying on auto-mapping.

[StudyofNeural]

Hi, I just fix this exception by downgrading the version of mybatis from 3.5.3 to 3.4.1 and then it works,but I’m steal confusing why it works? By the way,the same jar file could run successfully im my pc,but it ran failed in docker container. The jdk version in my pc is jdk1.8 but in docker is openjdk1.8,does the problem influenced by the jdk version? I can only figure out the diference between my pc and docker container. Hope you soon,thanks again…

The issue was closed by the author. I think you can make a new issue and give more details. 😃

OK,I’ll create a new issue soon