推土机：Hibernate PersistentMap没有映射到java.util.HashMap [英] Dozer: Hibernate PersistentMap is not mapped to java.util.HashMap

问题描述

我有一个带有字段的Hibernate注释实体：

$ $ p $ @OneToMany（mappedBy =templateInstance，fetch = FetchType。 EAGER）
@MapKey（name =attributeName）
私人地图< String，Component>组件;


Hibernate使PersistentMap不在此列。
然后我想让Dozer把它映射到一个有这样一个字段的对象：

  private Map< String，ComponentDto>组件; 
  

在LazyInitializationExceptions和一些调试之后，我发现它不是关闭的问题Hibernate会话，但Dozer尝试不映射到HashMap而是映射到PersistentMap！因此，当Dozer访问目标映射时，PersistentMap会抛出Exception，因为它当然没有会话。

所以，我认为Dozer的内部行为是映射到一个HashMap。现在的问题是：我做了什么错误或Dozer，我如何让Dozer将PersistentMap映射到普通Java标准映射？

使用List时没有问题之前。有没有其他人使用Dozer来映射Hibernate PersistentMap？

问候，
Konsumierer

解决方案

我自己找到了解决方案。 DTO中的组件字段必须如下所示：

  HashMap< String，Component> components = new HashMap< String，Component> ;; 
  

只有这样才能防止Dozer将PersistentMap作为目标对象。

另一个重要的事情是使用一个自定义的BeanMappingBuilder来存放映射，看起来像这样：

  public class TemplateInstanceMappingBuilder extends BeanMappingBuilder {
 $ b @Override 
 protected void configure（）{
 
 mapping（TemplateInstance.class，TemplateInstanceDto。 class）
 .fields（components，components，FieldsMappingOptions.hintB（ComponentDto.class））; 
 
 
 
 
 
 
有关该问题的更多信息，请参阅 https：// sourceforge中的Dozer论坛。 net / projects / dozer / forums / forum / 452530 / topic / 4020856 / index / page / 1   
I have a Hibernate annotated entity with a field: 
@OneToMany(mappedBy="templateInstance", fetch = FetchType.EAGER) 
@MapKey(name = "attributeName") 
private Map<String, Component> components; 
Hibernate makes a PersistentMap out of this. 
Then I want Dozer to map this to an object with such a field: 
private Map<String, ComponentDto> components; 
After having LazyInitializationExceptions and some debugging, I found out, that it´s not a problem of a closed Hibernate session, but that Dozer tries not to map to a HashMap but to a PersistentMap! And therefore when Dozer accesses the target map the PersistentMap throws the Exception, because it has no session of course. 

So, I thought that the intented behaviour of Dozer is to map to a HashMap. Now the question: am I doing something wrong or Dozer and how can I get Dozer to map the PersistentMap to normal Java standard map?

I had no problems when using a List before. Has anybody else used Dozer for mapping Hibernate PersistentMap?

Regards,
Konsumierer
解决方案
I found the solution by myself. The components field in the DTO has to look like this:
HashMap<String, Component> components = new HashMap<String, Component>;
Only this way you can prevent Dozer from using the PersistentMap as the target object.

And the other important thing is to use a custom BeanMappingBuilder for the DO that holds the map and that looks like that:
public class TemplateInstanceMappingBuilder extends BeanMappingBuilder {

    @Override
    protected void configure() {

        mapping(TemplateInstance.class, TemplateInstanceDto.class)
            .fields("components", "components", FieldsMappingOptions.hintB(ComponentDto.class));

    }
}
For further information about that problem, see the Dozer forums at https://sourceforge.net/projects/dozer/forums/forum/452530/topic/4020856/index/page/1

                        
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