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The Java code snippet you've provided uses a method to query database records and intends to return a list of IDs from the SYS_MENU table. However, there are a few issues in the code that need to be addressed to make it functional and correct in terms of Java and common JDBC operations. I'll provide a corrected version and explain each change.

make it functional and correct: 使事物（在这里是code）达到功能性和正确性的状态。
in terms of: 从……方面来说，就……而言，用于指明衡量、比较或描述某事物的标准或范围。

Original Code Issues

1. Type Handling in ArrayListHandler: The ArrayListHandler from Apache Commons DbUtils is typically used to return ArrayList<Object[]> where each Object[] corresponds to a row in the result set. Using ArrayListHandler<Long>() is incorrect because it does not automatically convert the result set into a list of Long.

2. Type Conversion: Direct conversion or casting to Long isn't handled by ArrayListHandler.

Corrected Version

To return a list of Long, you can use ColumnListHandler<Long> which is more appropriate for this scenario since you're interested in a single column list of type Long.

scenario: 是指一个具体的情境或情况。
be interested in: 表示对某事物的兴趣或者关注点。

import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.ColumnListHandler;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.List;

public class DatabaseUtility {

    private static final QueryRunner RUNNER = new QueryRunner();

    public static List<Long> getMenuIds(Connection conn) throws SQLException {
        // SQL query that selects IDs based on certain conditions
        String querySql = "SELECT ID FROM SYS_MENU WHERE MTYPE = 'ORGMG' AND STATUS = 1";

        // Execute the query and obtain the result as a list of Long
        List<Long> result = RUNNER.query(conn, querySql, new ColumnListHandler<Long>(1));

        return result;
    }
}

Key Changes and Explanations:

1. ColumnListHandler: Used ColumnListHandler<Long> which is designed to fetch data from one column in all rows of a result set directly into a List<Long>. The constructor argument 1 refers to the first column in the selection, which is suitable since ID is the only column being selected.

2. QueryRunner Instance: I assumed that QueryRunner is already defined somewhere as RUNNER. If not, you should initialize it as shown.

3. Error Handling: The method already throws SQLException, which is appropriate for database access methods where SQL operations are involved. It's good practice to handle these exceptions further up in your application logic.

Involved：与…相关的，涉及的。
Practice：习惯，惯例，最佳实践。
Further up：在更高层次，更上层。这里具体指在应用程序代码的调用链中更靠上的层次进行处理，而不是在当前的方法或函数中处理。

4. Imports: Make sure to import necessary classes (QueryRunner, ColumnListHandler, etc.) from Apache Commons DbUtils, which are required for the operations.

Additional Suggestions:

• Connection Management: Ensure that the connection passed to getMenuIds is managed (opened and closed) appropriately outside this method to avoid resource leaks.

passed to：含义是“被传递”或“传输给”。

• Parameterization: If your method later needs to handle various conditions dynamically, consider using parameterized queries to enhance flexibility and security (preventing SQL injection).

This revised method now should work correctly to fetch the list of IDs from the database and return them as a List<Long>.

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