java.sql.SQLExceptionColumnindexoutofrange. [数据库教程]

database

public <E> List<E> selectList(Mapper mapper, Connection conn){

PreparedStatement pstm = null;

ResultSet rs = null;

try{

String queryString = mapper.getQueryString();

String resultType = mapper.getResultType();

Class domainClass = Class.forName(resultType);

pstm = conn.prepareStatement(queryString);

rs = pstm.executeQuery();

List<E> list = new ArrayList<E>();

while(rs.next()){

E obj = (E)domainClass.newInstance();

ResultSetMetaData rsmd = rs.getMetaData();

int columnCount = rsmd.getColumnCount();

System.out.println(columnCount);

for(int i =0 ;i<=columnCount;i++){

//获取每列的名

String columnName = rsmd.getColumnName(i);

//获取每列值

Object columnValue = rs.getObject(columnName);

//给obj赋值，使用的是java内省机制（借助PropertyDescriptor实现属性的封装）

PropertyDescriptor pd = new PropertyDescriptor(columnName,domainClass);

Method writeMethod = pd.getWriteMethod();

writeMethod.invoke(obj,columnValue);

}

list.add(obj);

}

return list;

}catch (Exception e){

throw new RuntimeException(e);

}

这样会报错

java.sql.SQLException: Column index out of range.

解决办法

java.sql.SQLException: Column index out of range.