英文:
Cannot close derby connection with EntityManagerFactory
问题
我需要在创建数据库后（并删除原始版本的数据库）将其压缩到一个 zip 文件中。使用 EntityManagerFactory 创建后，我关闭它以释放连接并操作数据库文件。
问题是，即使我关闭了 EntityManagerFactory，数据库目录仍然被阻止，因为它显示正在使用中（不应该？）。
我创建了一个重新创建问题的最小再现示例（MRE）...
import java.util.HashMap;
import java.util.Map;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
public class Main {
private static EntityManagerFactory entityManagerFactory;
public static void main(String[] args) {
String dbURL = "jdbc:derby:C:\\Users\\XXX\\Desktop\\MyDB;create=true";
Map<String, String> persistenceMap = new HashMap<String, String>();
persistenceMap.put("javax.persistence.jdbc.url", dbURL);
entityManagerFactory = Persistence.createEntityManagerFactory("PUBLIC", persistenceMap);
entityManagerFactory.close();
entityManagerFactory = null;
System.out.println("DONE");
//我现在应该能够删除数据库目录（但实际上不能）。
try {
Thread.sleep(Long.MAX_VALUE);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
英文:
I need to compress a database inside a zip file after it's been created (and delete the original version of the database). After creating it using EntityManagerFactory I close it so that the connection is freed and I can manipulate the database file.
The problem is that even if I close the EntityManagerFactory the database directory is still blocked because it says it is in use (it shouldn't?).
I created a mre recreating the problem...
import java.util.HashMap;
import java.util.Map;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
public class Main {
private static EntityManagerFactory entityManagerFactory;
public static void main(String[] args) {
String dbURL = "jdbc:derby:C:\\Users\\XXX\\Desktop\\MyDB;create=true";
Map<String, String> persistenceMap = new HashMap<String, String>();
persistenceMap.put("javax.persistence.jdbc.url", dbURL);
entityManagerFactory = Persistence.createEntityManagerFactory("PUBLIC", persistenceMap);
entityManagerFactory.close();
entityManagerFactory = null;
System.out.println("DONE");
//I should be able to delete the database directory now (I'm not).
try {
Thread.sleep(Long.MAX_VALUE);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
答案1
得分: 1
问题已解决，我必须关闭数据库。
try {
DriverManager.getConnection(
"jdbc:derby:" + TEMP + "/" + projectName + ";user=xxxx;password=xxxx;shutdown=true");
} catch (SQLException sqle) {
// 如果捕捉到异常，说明操作顺利
}
英文:
Problem solved, I had to shutdown the database.
try {
DriverManager.getConnection(
"jdbc:derby:" + TEMP + "/" + projectName + ";user=xxxx;password=xxxx;shutdown=true");
} catch (SQLException sqle) {
//If catches exception went well
}
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