转摘:http://www.javaweb1024.com/java/JavaWebzhongji/2015/04/08/528.html

freemarker  直接使用List来遍历set集合,可能会报错! 错误如下

Java代码

private Set<Article> articles = new HashSet<Article>();

Freemarker中遍历

[#list category.articles?chunk(5) as article1]
     <div>
         <ul>
              [#list article1 as article ]
                [#assign articleDesc=i18n_description(article.articleDescriptions,true)/]
                [#if articleDesc!=null]
         ${abbreviate(articleDesc.title, 80, "...")}
         [/#if]
            [/#list]
          </ul>
      </div>
 [/#list]

报错信息

Underlying collection is not a list, it's org.hibernate.collection.internal.PersistentSet

freemarker.template.TemplateModelException: Underlying collection is not a list, it's org.hibernate.collection.internal.PersistentSet

at freemarker.ext.beans.CollectionModel.get(CollectionModel.java:127)

at freemarker.core.SequenceBuiltins$chunkBI$ChunkedSequence$1.get(SequenceBuiltins.java:792)

at freemarker.core.IteratorBlock$Context.runLoop(IteratorBlock.java:176)

at freemarker.core.Environment.visit(Environment.java:428)

at freemarker.core.IteratorBlock.accept(IteratorBlock.java:102)

at freemarker.core.Environment.visit(Environment.java:221)

at freemarker.core.MixedContent.accept(MixedContent.java:92)

at freemarker.core.Environment.visit(Environment.java:221)

at freemarker.core.IteratorBlock$Context.runLoop(IteratorBlock.java:179)

at freemarker.core.Environment.visit(Environment.java:428)

at freemarker.core.IteratorBlock.accept(IteratorBlock.java:102)

at freemarker.core.Environment.visit(Environment.java:221)

at freemarker.core.MixedContent.accept(MixedContent.java:92)

at freemarker.core.Environment.visit(Environment.java:221)

at freemarker.core.ConditionalBlock.accept(ConditionalBlock.java:79)

at freemarker.core.Environment.visit(Environment.java:221)

at freemarker.core.MixedContent.accept(MixedContent.java:92)

at freemarker.core.Environment.visit(Environment.java:221)

at freemarker.core.ConditionalBlock.accept(ConditionalBlock.java:79)

at freemarker.core.Environment.visit(Environment.java:221)

at freemarker.core.MixedContent.accept(MixedContent.java:92)

at freemarker.core.Environment.visit(Environment.java:221)

at freemarker.core.IteratorBlock$Context.runLoop(IteratorBlock.java:167)

at freemarker.core.Environment.visit(Environment.java:428)

at freemarker.core.IteratorBlock.accept(IteratorBlock.java:102)

at freemarker.core.Environment.visit(Environment.java:221)

at freemarker.core.Environment$1.render(Environment.java:246)

at com.eecart.template.directive.BaseDirective.setLocalVariable(BaseDirective.java:184)

at com.eecart.template.directive.ArticleCategoryRootListDirective.execute(ArticleCategoryRootListDirective.java:51)

at freemarker.core.Environment.visit(Environment.java:274)

at freemarker.core.UnifiedCall.accept(UnifiedCall.java:126)

at freemarker.core.Environment.visit(Environment.java:221)

解决方案:

不直接使用 articles

@Transient

public List<Article> getMyArticles(){

List<Article> list = new ArrayList<Article>(articles);

return list;

}

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