如何使用 jackson 为单个密钥的多个节点创建 JSON

Question

我想在 Java 中使用 Jackson 创建一个像下面这样的 JSON。我能够做到这一点，但只有一把钥匙。在这种情况下，“TestProject1-staging”无法同时保存“children”和“vars”。

 "TestProject1-staging": {
    "children" : [ "TestProject1-staginga", "TestProject1-stagingb", "TestProject1-stagingc" ],
    "vars": {
        "projects": {
            "TestProject1": {
                "app_tier": "apptier",
                "remote_dir": "/release/Test1"
            }
        }
    }
}

这是我写的代码：

ObjectMapper mapper = new ObjectMapper();
ObjectNode projects = mapper.createObjectNode();
ObjectNode finalObj = mapper.createObjectNode();
ObjectNode proRootNode = mapper.createObjectNode();
ObjectNode children = mapper.createObjectNode();
ObjectNode proRoot = mapper.createObjectNode();
proRoot.put("app_tier", inventoryContainer.appTier);
proRoot.put("remote_dir", inventoryContainer.remoteDirectory);
proRootNode.set(projectRoot, proRoot);
projects.set("projects", proRootNode);
children.put("children", 
mapper.writerWithDefaultPrettyPrinter().writeValueAsString(inventoryContainer.groups));
stagingVarNotSet = false;
finalObj.set(inventoryContainer.projectName, children);
varNode.set("vars", projects);
//finalObj.set(inventoryContainer.projectName, varNode);
System.out.println(StringEscapeUtils.unescapeJava(
     mapper.writerWithDefaultPrettyPrinter().writeValueAsString(finalObj)));

如您所见，注释行试图设置 vars 变量。如果我取消注释，将打印 vars 但 children 将丢失。在当前格式中，它打印 children 但不打印 vars.

那么我怎样才能将它们同时打印出来呢？

Answer 1

检查这是否适合您。

JSonCreator.java

package json;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ArrayNode;
import com.fasterxml.jackson.databind.node.ObjectNode;

public class JSonCreator {
    public static void main(String[] args) {
        ObjectMapper mapper = new ObjectMapper();
        JsonNode rootNode = mapper.createObjectNode();

        // Create TestProject1 JSON Object
        ObjectNode testProject1Node = mapper.createObjectNode();
        testProject1Node.put("app_tier", "apptier");
        testProject1Node.put("remote_dir", "/release/Test1");

        // Create projects JSON Object
        ObjectNode projectsNode = mapper.createObjectNode();
        projectsNode.set("TestProject1", testProject1Node);

        // Create vars JSON Object
        ObjectNode varsNode = mapper.createObjectNode();
        varsNode.set("projects", projectsNode);

        // Create children JSON Array
        ArrayNode childrenArrayNode = mapper.createArrayNode();
        childrenArrayNode.add("TestProject1-staginga");
        childrenArrayNode.add("TestProject1-stagingb");
        childrenArrayNode.add("TestProject1-stagingc");

        // Create children JSON object
        ObjectNode childrenNode = mapper.createObjectNode();
        childrenNode.set("children", childrenArrayNode);

        // Create TestProject1-staging" JSON object
        ObjectNode testProject1stagingNode = mapper.createObjectNode();
        testProject1stagingNode.set("children", childrenArrayNode);
        testProject1stagingNode.set("vars", varsNode);

        // append into root node
        ((ObjectNode) rootNode).set("TestProject1-staging",
                testProject1stagingNode);

        // convert ObjectNode to pretty-print JSON
        String json = null;
        try {
            json = mapper.writerWithDefaultPrettyPrinter().writeValueAsString(
                    rootNode);
            // print json
            System.out.println(json);
        } catch (JsonProcessingException e) {
            e.printStackTrace();
        }
    }
}

输出：

{
  "TestProject1-staging" : {
    "children" : [ "TestProject1-staginga", "TestProject1-stagingb", "TestProject1-stagingc" ],
    "vars" : {
      "projects" : {
        "TestProject1" : {
          "app_tier" : "apptier",
          "remote_dir" : "/release/Test1"
        }
      }
    }
  }
}

如何使用 jackson 为单个密钥的多个节点创建 JSON

How to create JSON for multiple nodes for a single key with jackson

java

json

jackson