连接到嵌入式Derby数据库时出现java.lang.NoClassDefFoundError

问题描述

我在嵌入式模式下使用Apache NetBeans IDE 11.3(带有JDK 13)和Derby.连接到数据库时出现以下错误:

I'm using Apache NetBeans IDE 11.3 (with JDK 13) and Derby in Embedded Mode. I am getting the following error while connecting to the database:

Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/derby/iapi/jdbc/JDBCBoot
    at org.apache.derby.jdbc.EmbeddedDriver.<clinit>(EmbeddedDriver.java:95)
    at Testing.testConnection.main(testConnection.java:15)
Caused by: java.lang.ClassNotFoundException: org.apache.derby.iapi.jdbc.JDBCBoot
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:602)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
    ... 2 more

以下是代码:

package Testing;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import org.apache.derby.jdbc.EmbeddedDriver;

public class testConnection {

    public static void main(String[] args) {

        try {
            DriverManager.registerDriver(new EmbeddedDriver());

            Connection con = DriverManager.getConnection("jdbc:derby:testdb;create=true");
            Statement stmt = con.createStatement();

            stmt.execute("create table test(id int(2) primary key, name varchar not null);");
            stmt.execute("insert into test values (01, 'Jeff'), (02, 'Clint'), (03, 'Mike');");

            ResultSet rs = stmt.executeQuery("select * from test;");

            while (rs.next()) {
                System.out.println(rs.getString("id") + "\t" + rs.getString("name"));
            }

            DriverManager.getConnection("jdbc:derby:;shutdown=true");
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

}

我不知道出了什么问题.我认为我没有正确设置数据库，但不确定.我是Derby和嵌入式数据库的新手.以前使用过MySQL，但要容易得多.任何帮助将不胜感激.

I don't know what goes wrong. I think I've not setup the database properly but I'm not sure. I'm new to Derby and Embedded Databases. Used MySQL before but it was a lot easier. Any help will be appreciated.

更新:

我看到我以前没有将derby.jar添加到依赖项中(我只是在使用derbytools.jar)，所以我添加了它，现在出现以下错误:

I saw that I didn't add 'derby.jar' to the dependencies before (I was just using 'derbytools.jar'), so I added it and now I'm getting the following error:

java.lang.NoClassDefFoundError: org/apache/derby/shared/common/security/SystemPermission
    at org.apache.derby.iapi.jdbc.JDBCBoot.boot(JDBCBoot.java:93)
    at org.apache.derby.iapi.jdbc.JDBCBoot.boot(JDBCBoot.java:68)
    at org.apache.derby.jdbc.EmbeddedDriver.<clinit>(EmbeddedDriver.java:95)
    at Testing.testConnection.main(testConnection.java:15)
Caused by: java.lang.ClassNotFoundException: org.apache.derby.shared.common.security.SystemPermission
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:602)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
    ... 4 more

推荐答案

如 Mark Rotteveel 中的建议注释，将 derbyshared.jar 以及 derby.jar 和 derbytools.jar 一起添加到依赖项中，并且我不再遇到该错误.我非常感谢他的帮助.谢谢.

As suggested by Mark Rotteveel in the comments, adding derbyshared.jar along with derby.jar and derbytools.jar to the dependencies worked and I'm no longer getting that error. I very very much appreciate his help. Thank you.

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