在 java 应用程序中实现自定义 jar 时出错

Question

我为我的自定义编码创建了新的 jar 文件，当我将这个 jar 文件添加到我的新项目时它抛出了 "package does not exist" 和 "cannot find symbol" 错误。

jar 文件有一个 class， AbstractDao.class

package kar;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.Query;

import java.util.List;

public abstract class AbstractDao {
    private Session session;
    private Transaction tx;

    public AbstractDao() {
        HibernateFactory.buildIfNeeded();
    }

    protected void saveOrUpdate(Object obj) {
        try {
            startOperation();
            session.saveOrUpdate(obj);
            tx.commit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }

    protected void delete(Object obj) {
        try {
            startOperation();
            session.delete(obj);
            tx.commit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }

    protected Object find(Class clazz, Long id) {
        Object obj = null;
        try {
            startOperation();
            obj = session.load(clazz, id);
            tx.commit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
        return obj;
    }

    protected List findAll(Class clazz) {
        List objects = null;
        try {
            startOperation();
            Query query = session.createQuery("from " + clazz.getName());
            objects = query.list();
            tx.commit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
        return objects;
    }

    protected void handleException(HibernateException e) throws DataAccessLayerException {
        HibernateFactory.rollback(tx);
        throw new DataAccessLayerException(e);
    }

    protected void startOperation() throws HibernateException {
        session = HibernateFactory.openSession();
        tx = session.beginTransaction();
    }
}

我的实现 class 是，

UserService.java

package obs.service;

import kar.AbstractDao;
import kar.DataAccessLayerException;
import obs.domain.User;

import org.springframework.stereotype.Service;

@Service("IUserService")
public class UserService extends AbstractDao {


 public UserService() {
  super();
 }

 public void create(User event) throws DataAccessLayerException {
  super.saveOrUpdate(event);
 }
}

这里我将 AbstractDao.class 文件放入 jar 中，在 UserService.java 中我实现了 AbstractDao class.

这是我得到的错误，

Answer 1

您出错的可能原因是您没有将自定义 jar 正确安装到本地 maven 存储库。

按如下方式将 jar 安装到本地存储库。

mvn install:install-file
   -Dfile=<path-to-file>
   -DgroupId=<group-id>
   -DartifactId=<artifact-id>
   -Dversion=<version>
   -Dpackaging=<packaging>
   -DgeneratePom=true

Where: <path-to-file>  the path to the file to load
   <group-id>      the group that the file should be registered under
   <artifact-id>   the artifact name for the file
   <version>       the version of the file
   <packaging>     the packaging of the file e.g. jar

Reference

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