• Hibernate 中update hql语句


    今天在MySQL中用hibernate测试update语句发现以下问题:

       update语句竟然不去作用;

    表机构如下:

    create table student
    (sid int primary key ,
    sname varchar(45) not null,
    ssex char(2) not null,
    sdept varchar(10) not null,
    sage int ,
    saddress varchar(45)
    );

    update语句如下:

    String[] params = new String[] { "20", "成龙" };

    HibernateUtil.executeUpdate(
    "update Student s set s.sage=? where s.sname=?",params);

    package com.huml.util;
    
    import java.util.ArrayList;
    import java.util.Arrays;
    
    import org.hibernate.Transaction;
    
    import org.hibernate.Query;
    import org.hibernate.Session;
    import org.hibernate.SessionFactory;
    import org.hibernate.cfg.Configuration;
    
    public class HibernateUtil {
        private static final SessionFactory sf;
        private static ThreadLocal<Session> threadLocal = new ThreadLocal<Session>();
        static {
            sf = new Configuration().configure().buildSessionFactory();
        }
    
        private HibernateUtil() {
    
        }
    
        public static Session openSession() {
            return sf.openSession();
        }
    
        public static Session getcurrentSession() {
            Session session = threadLocal.get();
    
            if (session == null) {
                session = sf.openSession();
                threadLocal.set(session);
            }
            return session;
        }
    
        public static void save(Object obj) {
            Session session = openSession();
            Transaction tx = null;
    
            try {
                tx = session.beginTransaction();
                session.save(obj);
                tx.commit();
            } catch (Exception e) {
                if (tx != null) {
                    tx.rollback();
                }
                throw new RuntimeException(e.getMessage());
            } finally {
                if (session != null && session.isOpen()) {
                    session.close();
                }
            }
        }
    
        @SuppressWarnings("unchecked")
        public static ArrayList executeQuery(String hql, String... params) {
            Session session = openSession();
            Transaction tx = null;
            ArrayList list = null;
            try {
                tx = session.beginTransaction();
                Query query = session.createQuery(hql);
    
                if (params != null && params.length > 0) {
                    for (int i = 0; i < params.length; i++) {
                        query.setParameter(i, params[i]);
                    }
                }
                list = (ArrayList) query.list();
                tx.commit();
            } catch (Exception e) {
                if (tx != null)
                    tx.rollback();
                throw new RuntimeException(e.getMessage());
            } finally {
                if (session != null && session.isOpen()) {
                    session.close();
                }
            }
            return list;
        }
    
        public static void executeUpdate(String hql, String... params) {
    
            Session session = openSession();
            Transaction tx = null;
    
            try {
                tx = session.beginTransaction();
                Query query = session.createQuery(hql);
    
                if (params != null && params.length > 0) {
                    for (int i = 0; i < params.length; i++) {
                        query.setParameter(i, params[i]);
                        // System.out.println("query influenced: "+params[i]);
                    }
                }
                System.out.println("query influenced: " + query.getQueryString());
                int n = query.executeUpdate();
                System.out.println("query influence: " + n);
                tx.commit();
            } catch (Exception e) {
                if (tx != null)
                    tx.rollback();
                throw new RuntimeException(e.getMessage());
            } finally {
                if (session != null && session.isOpen()) {
                    session.close();
                }
            }
        }
        
    }

    原因是MySQL中不能自动把String类型转换成Integer,在Oracle中可以修改代码如下:

    Object[] params = new Object[] { 20, "成龙" };

    HibernateUtil.executeUpdate(
    "update Student s set s.sage=? where s.sname=?",params);

    package com.huml.util;
    
    import java.util.ArrayList;
    import java.util.Arrays;
    
    import org.hibernate.Transaction;
    
    import org.hibernate.Query;
    import org.hibernate.Session;
    import org.hibernate.SessionFactory;
    import org.hibernate.cfg.Configuration;
    
    public class HibernateUtil {
        private static final SessionFactory sf;
        private static ThreadLocal<Session> threadLocal = new ThreadLocal<Session>();
        static {
            sf = new Configuration().configure().buildSessionFactory();
        }
    
        private HibernateUtil() {
    
        }
    
        public static Session openSession() {
            return sf.openSession();
        }
    
        public static Session getcurrentSession() {
            Session session = threadLocal.get();
    
            if (session == null) {
                session = sf.openSession();
                threadLocal.set(session);
            }
            return session;
        }
    
        public static void save(Object obj) {
            Session session = openSession();
            Transaction tx = null;
    
            try {
                tx = session.beginTransaction();
                session.save(obj);
                tx.commit();
            } catch (Exception e) {
                if (tx != null) {
                    tx.rollback();
                }
                throw new RuntimeException(e.getMessage());
            } finally {
                if (session != null && session.isOpen()) {
                    session.close();
                }
            }
        }
    
        @SuppressWarnings("unchecked")
        public static ArrayList executeQuery(String hql, String... params) {
            Session session = openSession();
            Transaction tx = null;
            ArrayList list = null;
            try {
                tx = session.beginTransaction();
                Query query = session.createQuery(hql);
    
                if (params != null && params.length > 0) {
                    for (int i = 0; i < params.length; i++) {
                        query.setParameter(i, params[i]);
                    }
                }
                list = (ArrayList) query.list();
                tx.commit();
            } catch (Exception e) {
                if (tx != null)
                    tx.rollback();
                throw new RuntimeException(e.getMessage());
            } finally {
                if (session != null && session.isOpen()) {
                    session.close();
                }
            }
            return list;
        }
    
        public static void executeUpdate(String hql, Object... params) {
    
            Session session = openSession();
            Transaction tx = null;
    
            try {
                tx = session.beginTransaction();
                Query query = session.createQuery(hql);
    
                if (params != null && params.length > 0) {
                    for (int i = 0; i < params.length; i++) {
                        query.setParameter(i, params[i]);
                        // System.out.println("query influenced: "+params[i]);
                    }
                }
                System.out.println("query influenced: " + query.getQueryString());
                int n = query.executeUpdate();
                System.out.println("query influence: " + n);
                tx.commit();
            } catch (Exception e) {
                if (tx != null)
                    tx.rollback();
                throw new RuntimeException(e.getMessage());
            } finally {
                if (session != null && session.isOpen()) {
                    session.close();
                }
            }
        }
    }

    这样就成功了;

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  • 原文地址:https://www.cnblogs.com/ronaldHU/p/3806681.html
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