2017-02-09 124 views
0

我有一些字段要在hashmap中更新,我试图把它放在session.update(对象对象)。但我得到异常错误为未知实体:java.util.HashMap。这是我的代码。是否有可能更新特定字段休眠

private Map <String, Object> conditions=new HashMap <String, Object>(); 
    public void addCondition(String field, Object condition){ 
      conditions.put(field, condition); 
     } 
    public Object getFilter(String field){ 
      return conditions.get(field); 
     } 
    public Map<String,Object>getFilterMap(){   
      return conditions; 
     } 

更新这些字段:

class_name.addCondition("loginName", "dadan_evil"); 
    class_name.addCondition("lastName", "Pirate"); 
    session.update(filter.getFilterMap());//I tried this, but not working 

User.hbm.xml:

<?xml version="1.0" encoding="utf-8"?> 
<!DOCTYPE hibernate-mapping PUBLIC 
"-//Hibernate/Hibernate Mapping DTD//EN" 
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> 

<hibernate-mapping> 
    <class name="in.co.User" table="user"> 
     <meta attribute="class-description"> 
     This class contains the user detail. 
     </meta> 
     <id name = "loginName" type="string" column="loginName"> 

     </id> 
     <property name="passCode" column="passCode" type="string"/> 
     <property name="firstName" column="firstName" type="string"/> 
     <property name="lastName" column="lastName" type="string"/> 
     <property name="alternateEMail" column="alternateEMail" type="string"/> 
     <property name="mobile" column="mobile" type="string"/> 
     <property name="sysAdmin" column="sysAdmin" type="boolean"/> 
     <property name="deleted" column="deleted" type="boolean"/> 
     <property name="authenticationCode" column="authenticationCode" type="string"/> 
     <property name="authenticated" column="authenticated" type="boolean"/> 

    </class> 
</hibernate-mapping> 

我的更新方法:

private static void updateFromQuery(DBFilter filter) throws Exception { 
     Session session = factory.openSession(); 

     try{ 
      Class<?> className = filter.getCollectionClass(); 
      Criteria criteria = session.createCriteria(className); 
      criteria.add(Restrictions.allEq(filter.getFilterMap())); 
      //I dont know how to update this, just an imaginary parameter 
      session.update(filter.getFilterMap()); 

     }catch(HibernateException e){ 
      e.printStackTrace(); 
     }finally{ 
      session.close(); 
     } 
    } 

,我不能写下一个字符串查询要么因为我有多个表格和不同的值。而且我甚至动态地获得类名称。所以我不能使用字符串查询来为所有人共同使用。所以,如果我可以的话,请告诉我。

现在,我该如何更新这两个值到数据库。请帮助

+0

您正尝试将java.util.HashMap直接存储在您的数据库中!你确定你要这么做吗? – mwe

+0

您无法将hashmap传递给update()方法....您应该传递由@Entity批注注释的实体。从地图提取值并将它们放在实体类中,然后简单地更新 –

+0

您是否已经使用Hibernate?你知道Hibernate是用于持久化整个对象(规定哪个属性映射到哪个字段),而不是用于搜索表名然后愚蠢地创建sql-update-statements? –

回答

0

我已经通过使用java.lang.reflect.Field来完成它。所以我从数据库中检索了特定的对象,并且我将从Map中分离出键和值,并通过引用我需要的Class来与Field绑定。现在这工作正常。即使我得到比我的更好的答案,它的确定。

private static void setField(Class<?> class_name,Object object, String fieldName, Object value) throws Exception { 
     Field field = class_name.getDeclaredField(fieldName);  
     field.setAccessible(true); 
     field.set(object, value);  
    } 

    private static void updateFromQuery(DBFilter filter) throws Exception { 
     Session session = factory.openSession(); 

     try { 
      Class<?> className = filter.getCollectionClass(); 
      Criteria criteria = session.createCriteria(className); 
      criteria.add(Restrictions.allEq(filter.getFilterMap())); 
      List objectList = criteria.list(); 
      Transaction tx; 
      tx = session.beginTransaction(); 
      for (Object object : objectList) { 
       for (Map.Entry<String, Object> entry : filter.getValueMap().entrySet()) { 
        setField(className,object, entry.getKey(), entry.getValue()); 
       } 
       session.update(object); 
      } 
      tx.commit(); 
     } catch (HibernateException e) { 
      e.printStackTrace(); 
     } finally { 
      session.close(); 
     } 
    } 

感谢大家谁支持。