cn.zhuqi.mavenssh.dao.impl.GenericDAO.java Source code

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Here is the source code for cn.zhuqi.mavenssh.dao.impl.GenericDAO.java

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package cn.zhuqi.mavenssh.dao.impl;

import cn.zhuqi.mavenssh.dao.IGenericDAO;
import java.util.List;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;

/**
 *
 * @author Administrator
 * @param <T>
 */
public class GenericDAO<T> implements IGenericDAO<T> {

    private final Class<T> entityClass;

    public GenericDAO(Class<T> entityClass) {
        this.entityClass = entityClass;
    }

    @Autowired
    private SessionFactory sessionFactory;

    protected Session getSession() {
        return sessionFactory.getCurrentSession();
    }

    @Override
    public void insert(T t) {
        getSession().save(t);
    }

    @Override
    public void delete(T t) {
        getSession().delete(t);
    }

    @Override
    public void update(T t) {
        getSession().merge(t);
    }

    @SuppressWarnings("unchecked")
    @Override
    public T queryById(Integer id) {
        return (T) getSession().get(entityClass, id);
    }

    @Override
    public List<T> queryAll() {
        String hql = "from " + entityClass.getSimpleName();
        return queryForList(hql, null);
    }

    @SuppressWarnings("unchecked")
    protected T queryForObject(String hql, Object[] params) {
        Query query = getSession().createQuery(hql);
        setQueryParams(query, params);
        return (T) query.uniqueResult();
    }

    @SuppressWarnings("unchecked")
    protected T queryForTopObject(String hql, Object[] params) {
        Query query = getSession().createQuery(hql);
        setQueryParams(query, params);
        return (T) query.setFirstResult(0).setMaxResults(1).uniqueResult();
    }

    @SuppressWarnings("unchecked")
    protected List<T> queryForList(String hql, Object[] params) {
        Query query = getSession().createQuery(hql);
        setQueryParams(query, params);
        return query.list();
    }

    @SuppressWarnings("unchecked")
    protected List<T> queryForList(final String hql, final Object[] params, final int recordNum) {
        Query query = getSession().createQuery(hql);
        setQueryParams(query, params);
        return query.setFirstResult(0).setMaxResults(recordNum).list();
    }

    private void setQueryParams(Query query, Object[] params) {
        if (null == params) {
            return;
        }
        for (int i = 0; i < params.length; i++) {
            query.setParameter(i, params[i]);
        }
    }

}