


Why Am I Getting 'SQLException: Operation Not Allowed After ResultSet Closed' in My Java Code?
"SQLException: Operation Not Allowed After ResultSet Closed" - Troubleshooting and Solutions
Encountering the "java.sql.SQLException: Operation not allowed after ResultSet closed" exception typically indicates a problem with handling ResultSets in your Java code. To resolve this issue, let's delve into the scenario presented in the question.
The code snippet provided involves executing multiple queries within a try-catch block. It begins by using a Statement object to retrieve data from the "user" table, followed by querying the "profiles" table to prepare a batch operation using a PreparedStatement object.
The problem arises within the getStuff() method, where a ResultSet is obtained without being closed, violating the default behavior of Statement. By having multiple ResultSets open simultaneously from the same Statement object, the code violates the expectation that only one ResultSet can be open at a time.
To rectify this issue, it's crucial to ensure that ResultSets are explicitly closed when they are no longer needed. For the code in question, this means adding a call to rs.close() after fetching data in both ResultSet objects (rs and rs2) and in the getStuff() method.
Additionally, it's worth noting that while database connections are designed to be reusable, it's generally recommended to create new Statement objects for each query to maintain optimal performance. This is especially important when dealing with batch operations, as it ensures that all queries are executed using the same Statement.
By following these recommendations, you can successfully resolve the "Operation not allowed after ResultSet closed" exception and ensure proper handling of ResultSets in your Java code.
The above is the detailed content of Why Am I Getting 'SQLException: Operation Not Allowed After ResultSet Closed' in My Java Code?. For more information, please follow other related articles on the PHP Chinese website!

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