如何解决org.simpleframework.xml.core.ValueRequiredException：无法满足@org.simpleframework.xml.ElementList()

Question

我正在尝试使用 Retrofit 从 URL 获取图书 xml 数据。但是当应用程序运行时，它显示错误。我是新来的所以请帮助我。这是错误信息：

    02-20 23:06:37.943 23835-23835/com.santossingh.reader E/error:
org.simpleframework.xml.core.ValueRequiredException: Unable to satisfy @org.simpleframework.xml.ElementList(data=false, empty=true, entry=, inline=true, name=work, required=true, type=void) on field 'works' public java.util.List com.santossingh.reader.AWS.GoodReadsModels.Results.works for class com.santossingh.reader.AWS.GoodReadsModels.Results at line 2

这是 XML 文件结构和我的模型以及类:

1- URL XML 文件的结构：

<?xml version="1.0" encoding="UTF-8"?>
        <GoodreadsResponse>
          <Request>
            <authentication>true</authentication>
              <key><![CDATA[xxxxx]]></key>
            <method><![CDATA[search_index]]></method>
          </Request>
          <search>
          <query><![CDATA[business]]></query>
            <results-start>1</results-start>
            <results-end>20</results-end>
            <total-results>109755</total-results>
            <source>Goodreads</source>
            <query-time-seconds>0.22</query-time-seconds>
            <results>
                <work>
          <id type="integer">17624817</id>
          <books_count type="integer">85</books_count>
          <ratings_count type="integer">156992</ratings_count>
          <text_reviews_count type="integer">8489</text_reviews_count>
          <original_publication_year type="integer">2011</original_publication_year>
          <original_publication_month type="integer" nil="true"/>
          <original_publication_day type="integer" nil="true"/>
          <average_rating>4.01</average_rating>
          <best_book type="Book">
            <id type="integer">12609433</id>
            <title>The Power of Habit: Why We Do What We Do in Life and Business</title>
            <author>
              <id type="integer">5201530</id>
              <name>Charles Duhigg</name>
            </author>
            <image_url>https://images.gr-assets.com/books/1366758683m/12609433.jpg</image_url>
            <small_image_url>https://images.gr-assets.com/books/1366758683s/12609433.jpg</small_image_url>
          </best_book>
        </work>
      <results>

Here is the clarity of structure <imagelink> of structure XML file for more clarity.

2- Results.class 的模型：

@Root (name = "results", strict = false)
public class Results {

    @ElementList (name = "work", inline = true)
    public List<Work> works;

    public Results() {
    }

    public Results(List<Work> works) {
        this.works = works;
    }

    public List<Work> getWorks() {
        return works;
    }

    public void setWorks(List<Work> works) {
        this.works = works;
    }
}

2- Work.class 的模型：

@Root(name = "work", strict = false)
public class Work {

    @Path("best_book")
    @Element(name = "id")
    private int id;

    @Path("best_book")
    @Element (name = "title")
    private String title;

    @Path("best_book/author")
    @Element(name = "name")
    private String author;

    @Path("best_book")
    @Element (name = "image_url")
    private String image;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }

    public String getImage() {
        return image;
    }

    public void setImage(String image) {
        this.image = image;
    }
}

Answer 1

我找到了答案。在 Result.class 中，只需更改 @ElementList() 参数。这是解决方案：

错误-

    @ElementList(name = "work", inline = true)
    public List<Work> works;

解决方案-

    @ElementList(inline = true, required = false)
    public List<Work> works;

每当发生该错误时，请记住@ElementList() 中的两件事

1- inline=true
2- required=false
example : @ElementList(inline = true, required = false)

Answer 2

我也遇到过这个问题。查看文档，它说如下。

The ValueRequiredException is thrown when an attribute or element is missing from the XML document. This is thrown only if the attribute or element is required according to the annotation for that field within the XML schema class.

基本上，当形成的请求与您的 XML 请求架构不匹配时，就会发生这种情况。

所以，使用注释

@ElementList(name="XMLNode", required = false)
public <<DataType>> XMLNode;

当 required = false 时，构建器将忽略标记并构建请求的剩余节点。

P.S: 当您使用相同的 class 形成 XML 请求并解析响应时，这主要有用。

如何解决org.simpleframework.xml.core.ValueRequiredException：无法满足@org.simpleframework.xml.ElementList()

How to solve org.simpleframework.xml.core.ValueRequiredException: Unable to satisfy @org.simpleframework.xml.ElementList()

xml

android

xml-serialization

simple-framework

retrofit2