2

为什么这段代码会出现错误？我不明白..请帮帮我。

我已经测试过了：doSave(), getListCount(), doDelete(),getDetails()都很好。

但是，在getList()方法中发生错误！

为什么？该方法没有参数，只有一个查询。

select * from tb_board_data

我的配置：mybatis 3.2.2 / mybatis-spring 1.2.0 / spring 3.2.2

package kr.co.goodwilldd.board.mapper;

import java.util.ArrayList;

import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.SelectKey;
import org.apache.ibatis.mapping.StatementType;
import org.springframework.stereotype.Repository;

@Repository
public interface CommonBoardMapper<T> {

    @Select(value = "SELECT COUNT(*) FROM TB_BOARD_DATA")
    public long getListCount();

    @Select(value = "SELECT * FROM TB_BOARD_DATA")
    public ArrayList<T> getList();

    @Select(value = "SELECT * FROM TB_BOARD_DATA WHERE bseq = #{_seq}")
    public T getDetails(long _seq);

    @SelectKey(before=true, keyProperty="bseq", statementType=StatementType.PREPARED, statement="SELECT (IFNULL(MAX(BSEQ),0)+1) as bseq FROM TB_BOARD_DATA", resultType=Long.class)
    @Insert(value = "INSERT INTO TB_BOARD_DATA(bseq, boardName, register, subject, content, reStep, reLevel, regdate) SELECT #{bseq}, #{boardName}, #{register}, #{subject}, #{content}, ifnull(((floor(max(reStep)/100))+1)*100+99, 199) , 0, CURRENT_DATE() FROM TB_BOARD_DATA")
    public int doSave(T t);

    @Delete(value = "DELETE FROM TB_BOARD_DATA WHERE bseq = #{_seq}")
    public int doDelete(long _seq);
}

此处的错误日志：

org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: 
### Error querying database.  Cause: java.lang.UnsupportedOperationException
### The error may exist in kr/co/goodwilldd/board/mapper/CommonBoardMapper.java (best guess)
### The error may involve defaultParameterMap
### The error occurred while setting parameters
### SQL: SELECT * FROM TB_BOARD_DATA
### Cause: java.lang.UnsupportedOperationException
    at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:73)
    at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:364)
    at com.sun.proxy.$Proxy13.selectList(Unknown Source)
    at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:194)
    at org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:114)
    at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:58)
    at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:43)
    at com.sun.proxy.$Proxy25.getList(Unknown Source)
    at kr.co.goodwilldd.board.CommonBoardTest.getListByMapper(CommonBoardTest.java:31)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28)
    at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:74)
    at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:83)
    at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:72)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:231)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:88)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
    at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
    at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:71)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:174)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: org.apache.ibatis.exceptions.PersistenceException: 
### Error querying database.  Cause: java.lang.UnsupportedOperationException
### The error may exist in kr/co/goodwilldd/board/mapper/CommonBoardMapper.java (best guess)
### The error may involve defaultParameterMap
### The error occurred while setting parameters
### SQL: SELECT * FROM TB_BOARD_DATA
### Cause: java.lang.UnsupportedOperationException
    at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:23)
    at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:107)
    at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:98)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:354)
    ... 36 more
Caused by: java.lang.UnsupportedOperationException
    at org.apache.ibatis.reflection.wrapper.CollectionWrapper.findProperty(CollectionWrapper.java:42)
    at org.apache.ibatis.reflection.MetaObject.findProperty(MetaObject.java:76)
    at org.apache.ibatis.executor.resultset.FastResultSetHandler.applyAutomaticMappings(FastResultSetHandler.java:342)
    at org.apache.ibatis.executor.resultset.FastResultSetHandler.getRowValue(FastResultSetHandler.java:267)
    at org.apache.ibatis.executor.resultset.FastResultSetHandler.handleRowValues(FastResultSetHandler.java:216)
    at org.apache.ibatis.executor.resultset.FastResultSetHandler.handleResultSet(FastResultSetHandler.java:188)
    at org.apache.ibatis.executor.resultset.FastResultSetHandler.handleResultSets(FastResultSetHandler.java:154)
    at org.apache.ibatis.executor.statement.PreparedStatementHandler.query(PreparedStatementHandler.java:57)
    at org.apache.ibatis.executor.statement.RoutingStatementHandler.query(RoutingStatementHandler.java:70)
    at org.apache.ibatis.executor.ReuseExecutor.doQuery(ReuseExecutor.java:54)
    at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:259)
    at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:132)
    at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:105)
    at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:81)
    at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:104)
    ... 42 more
4

6 回答 6

6

您应该指定一个具体类型作为返回类型，例如

List<Customer> getList();

，但没有泛型类型

List<T> getList();

或者

List getList();

因为如果你指定了类型，mybatis 会使用 BeanWrapper 将每一行转换为类型。但是如果没有具体的类型，mybatis会把每一行都当成一个List，使用CollectionWrapper，不支持findProperty。

于 2013-05-15T15:11:38.237 回答
0

尝试这个：

@Select(value = "SELECT * FROM TB_BOARD_DATA")
public List<T> getList();
于 2014-02-02T05:52:57.190 回答
0

始终遵循接口代码:)

要么使用通用

@Select(value = "SELECT * FROM TB_BOARD_DATA")
public List<T> getList();

或非通用

 @Select(value = "SELECT * FROM TB_BOARD_DATA")
   public List<String> getList();
于 2015-03-13T04:08:30.177 回答
0

在以下情况下我遇到了同样的错误：

  1. 在 XML 映射器中，Oracle 表达式的String值为CHAR(table.coltime, 'DD.MM.YYYY')
  2. 我的返回类型得到了java.sql.Date代替。

修复消除了错误。

因此，错误可能是由于返回对象中的字段类型不合适而出现的。

于 2020-03-26T12:27:41.750 回答
0

如果您看到 OOPS 设计原则始终说“为接口编程而不是实现”。我们应该遵循这种做法，它将避免许多不希望的异常。

于 2016-04-20T06:49:56.103 回答
0

你的错误是

getList(Unknown Source)

请在调用该方法时提供相同的返回类型。 List表示 List 或ArrayList表示 ArrayList

于 2017-09-06T22:22:05.757 回答