Jackson Json：将Json Tree节点转换为Java对象并将其添加到ArrayList

Question

I'm still new to Java and parsing Json. I'm trying to build a Comic Webapp with Spring. The Database is a Json File, which holds an Array of different Comics. I wanted to convert the Json Array to Java Objects and put it into an ArrayList but I seem to make a mistake somewhere along the way. Maybe you can tell me what I'm doing wrong? While doing a JUnit Test I get the following error:

Error com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "Comic" (class de.uni_koeln.comics.data.Comic), not marked as ignorable (6 known properties: , "title", "issue", "id", "box", "publisher", "comment"])
 at [Source: N/A; line: -1, column: -1] (through reference chain: de.uni_koeln.comics.data.Comic["Comic"])

Comic.class

package de.uni_koeln.comics.data;

import de.uni_koeln.comics.service.JsonImportService;

public class Comic {
    private JsonImportService jservice;

public String title;
public int id;
public int issue;
public int box;
public String publisher;
public String comment;

public Comic() {

}
public Comic(String title, int issue, int box, String publisher, String   comment) {
        this.title = title;
        this.issue = issue;
        this.box = box;
        this.comment = comment;
        this.publisher = publisher;
    }

//setter and getter

` JsonImportService

package de.uni_koeln.comics.service;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;


@Service
public class JsonImportService {
    private List<Comic> comicList;

    @Test
    public void readComicJson() throws JsonParseException, JsonMappingException, IOException {

        ObjectMapper mapper = new ObjectMapper();
        JsonNode root = mapper.readTree(new File("src/main/resources/Comics.json"));
    Comic comic = mapper.treeToValue(root, Comic.class);

    JsonNode contactNode = root.path("Comic");
    if (contactNode.isArray()) {
        for (JsonNode node : contactNode) {

            String title = node.path("Title").asText();
            int issue = node.path("Issue #").asInt();
            int box = node.path("Box #").asInt();
            String publisher = node.path("Publisher").asText();
            String comment = node.path("Comments").asText();

            comic.setTitle(title);
            comic.setIssue(issue);
            comic.setBox(box);
            comic.setPublisher(publisher);
            comic.setComment(comment);
            comicList.add(new Comic(title,box,issue,publisher,comment));
        }
    }
}

public List<Comic> getComicList() {
    return comicList;
}

Answer 1

Try to use the @JsonIgnoreProperties annotation like blow.

@JsonIgnoreProperties(ignoreUnknown = true)

public class Comic {

}