Question

我在JAXB中做了简单的编组和解组，如何使用JAXB在我的xml中插入/删除/搜索元素。请提供代码段。

我的输入XML

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<comments>
<comment id="id-1">Text1</comment>
<comment id="id-2">Text2</comment>
<comment id="id-3">Text3</comment>
</comments>

java中的我的Mapping类

@XmlRootElement( name = "comments" )
public class CommentsNode {

    List<CommentNode> comments;

    @XmlElement( name = "comment" )
    public void setComments(List<CommentNode> comments){
        this.comments = comments;
    }

    public List<CommentNode> getComments(){
        return this.comments;
    }
}

@XmlRootElement( name = "comment" )
@XmlType(propOrder = { "id" })
public class CommentNode {

    String id = null;

    @XmlAttribute ( name = "id" )
    public void setId(String id){
        this.id = id;
    }

    public String getId(){
        return this.id;
    }
}

unmarshall代码：

File file = new File("/Users/vignesh-1200/Desktop/JAXB/sample.xml");
            //StreamSource s = new StreamSource(file);
            JAXBContext jaxbContext = JAXBContext.newInstance(CommentsNode.class);
            Unmarshaller jaxbUnmarshaller = jaxbContext.createUnmarshaller();
            CommentsNode commentsNode = (CommentsNode) jaxbUnmarshaller.unmarshal(file);

            List<CommentNode> childrens = commentsNode.getComments();
            if(childrens!=null){
                for(int i=0,j=childrens.size();i<j;i++){
                    CommentNode child = childrens.get(i);
                    System.out.println(child.getId()+":"+child.getUserId());    
                }
            }else{
                System.out.println("Childrens Empty");
            }

如何使用属性值在xml中获取特定元素。例如，id = 2。请帮助我。

Answer 1

在Java 8中足够简单：

commentsNode.getComments().stream()
    .filter(node -> node.getId() == 2)
    .findFirst().get()

使用JAXB插入/删除/搜索XML元素

1 个答案: