Lucene - 检索文档中多值字段的所有值

Lucene - retrieve all values for a multi-valued field in a document(Lucene - 检索文档中多值字段的所有值)

问题描述

我在 Lucene 中添加了一个多值字段:

I added a field in Lucene which is multi-valued as such:

String categoriesForItem = getCategories(); // returns "category1, category2, cat3" from a DB call

String [] categoriesForItems = categoriesForItem.split(","; 
for(String cat : categoriesForItems) {
    doc.add(new StringField("categories", cat , Field.Store.YES)); // doc is a Document 
}

稍后当我在某个类别中搜索项目时，一切都按预期工作，但是当我得到一个文档并执行以下操作时:

later when I am searching for items in a category everything works as expected, but when I get a Document and do:

String categories= doc.getField("categories").stringValue(); 

我只获取该文档的最后插入值，而不是为该文档添加的所有值.

I only get the last inserted value for that document rather than all the values that were added for that document.

如何获取为该文档添加的所有值?

How can I get all the values which were added for that document?

推荐答案

你添加到文档中的不是多值单字段，而是多个同名字段.最后，您只检索一个字段.

What you are adding to the document is not multi-valued single field, but multiple fields with the same name. At the end you are only retrieving one field.

使用 public final ListDocument 的 getFields() 代替.

Use public final List<IndexableField> getFields() of Document instead.

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