java.sql.SQLException：无效的游标状态：标识的游标未打开标识的游标未打开
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java.sql.SQLException:invalid cursor state: identified cursor is not open identified cursor is not open
提问by NARU
I am using Apache DBCP to get a pool of connections, I use PoolingDataSource to get a connection each time. It works well when I insert an object into the database, but problem occurs when I try to select an element from database: it always returns a DelegatingPreparedStatement and DelegatingResultSet, and if the next() method of DelegatingResuletSet executes, an error "java.sql.SQLException:invalid cursor state: identified cursor is not open identified cursor is not open" occurs. I don't know why, is there anybody know what the problem is? I am using HSQLDB. The codes are:
我使用 Apache DBCP 来获取连接池，我每次都使用 PoolingDataSource 来获取连接。当我将一个对象插入数据库时它运行良好，但是当我尝试从数据库中选择一个元素时出现问题：它总是返回一个 DelegatingPreparedStatement 和 DelegatingResultSet，如果 DelegatingResuletSet 的 next() 方法执行，则会出现错误“java.sql .SQLException：无效的游标状态：标识的游标未打开标识的游标未打开”发生。不知道是什么原因，有大佬知道是什么问题吗？我正在使用 HSQLDB。代码是：
String strSql = "select * from " + strTableName + " where " + strColumnName
+ " = ? ";
PreparedStatement aPreparedStatement = con.prepareStatement(strSql);
ResultSet aResultSet = null;
/*
* Execute the query
*/
try
{
aPreparedStatement.setString(1, strValue);
aResultSet = aPreparedStatement.executeQuery();
}
catch (SQLException theException)
{
aPreparedStatement.close();
throw theException;
}
aPreparedStatement.close();
while (theResultSet.next())
{
// do something else
}
Thanks for your help, Ike
谢谢你的帮助，艾克
回答by
You are closing the PreparedStatement before you are trying to iterate through the ResultSet. I don't think this is right - I think you should close them both at the same time, once you've retrieved all your results from the ResultSet object.
在尝试遍历 ResultSet 之前，您正在关闭 PreparedStatement。我不认为这是正确的 - 我认为您应该同时关闭它们，一旦您从 ResultSet 对象中检索了所有结果。
Edit: See the API for close():
编辑：请参阅close() 的 API：
"Note:When a Statement object is closed, its current ResultSet object, if one exists, is also closed."
“注意：当一个 Statement 对象关闭时，它当前的 ResultSet 对象（如果存在）也将关闭。”
回答by Om Yadav
Closing the Any Statement(Statement/PreparedStatement/CallableStatement) will generally closes the associated ResultSet Object. So try to close the ResultSet first and then the PreparedStatement object.
关闭 Any Statement(Statement/PreparedStatement/CallableStatement) 通常会关闭关联的 ResultSet 对象。所以尝试先关闭 ResultSet 再关闭 PreparedStatement 对象。
