开发中, 为了便于开发、调试, 难免会碰到要对JSON类型的字符串进行格式化显示的需求. 本文对常见的2种格式化方式进行了实测, 包括阿里的FastJson和谷歌的Gson, 并对过程作了完整的记录.

1 使用阿里的FastJson

1.1 项目的pom.xml依赖

<dependency>
  <groupId>com.alibaba</groupId>
  <artifactId>fastjson</artifactId>
  <version>1.2.58</version>
</dependency>

1.2 Java示例代码

(1) 导入的包:

com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.alibaba.fastjson.serializer.SerializerFeature;

(2) 测试代码:

其中JSON字符串为:

public static void main(String[] args) {
    String jsonString = "{\"_index\":\"book_shop\",\"_type\":\"it_book\",\"_id\":\"1\",\"_score\":1.0," +
            "\"_source\":{\"name\": \"Java编程思想(第4版)\",\"author\": \"[美] Bruce Eckel\",\"category\": \"编程语言\"," +
            "\"price\": 109.0,\"publisher\": \"机械工业出版社\",\"date\": \"2007-06-01\",\"tags\": [ \"Java\", \"编程语言\" ]}}";
    JSONObject object = JSONObject.parseObject(jsonString);
    String pretty = JSON.toJSONString(object, SerializerFeature.PrettyFormat, SerializerFeature.WriteMapNullValue, 
            SerializerFeature.WriteDateUseDateFormat);
    System.out.println(pretty);

(3) 格式化输出后的结果:

说明: FastJson通过Tab键进行换行后的格式化.

"_index":"book_shop", "_type":"it_book", "_source":{ "date":"2007-06-01", "author":"[美] Bruce Eckel", "price":109.0, "name":"Java编程思想(第4版)", "publisher":"机械工业出版社", "category":"编程语言", "tags":[ "Java", "编程语言" "_id":"1", "_score":1.0

2 使用谷歌的Gson

2.1 项目的pom.xml依赖

<dependency>
    <groupId>com.google.code.gson</groupId>
    <artifactId>gson</artifactId>
    <version>2.2.4</version>
</dependency>

2.2 Java示例代码

(1) 导入的包:

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonArray;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;

(2) 测试代码:

JSON字符串与上述测试代码相同.

public static void main(String[] args) {
    String jsonString = "{\"_index\":\"book_shop\",\"_type\":\"it_book\",\"_id\":\"1\",\"_score\":1.0," +
            "\"_source\":{\"name\": \"Java编程思想(第4版)\",\"author\": \"[美] Bruce Eckel\",\"category\": \"编程语言\"," +
            "\"price\": 109.0,\"publisher\": \"机械工业出版社\",\"date\": \"2007-06-01\",\"tags\": [ \"Java\", \"编程语言\" ]}}";
	String pretty = toPrettyFormat(jsonString)
	System.out.println(pretty);
 * 格式化输出JSON字符串
 * @return 格式化后的JSON字符串
private static String toPrettyFormat(String json) {
	JsonParser jsonParser = new JsonParser();
	JsonObject jsonObject = jsonParser.parse(json).getAsJsonObject();
	Gson gson = new GsonBuilder().setPrettyPrinting().create();
	return gson.toJson(jsonObject);

(3) 格式化输出后的结果:

说明: Gson使用2个空格作为换行后的格式转换.

"_index": "book_shop", "_type": "it_book", "_id": "1", "_score": 1.0, "_source": { "name": "Java编程思想(第4版)", "author": "[美] Bruce Eckel", "category": "编程语言", "price": 109.0, "publisher": "机械工业出版社", "date": "2007-06-01", "tags": [ "Java", "编程语言"

JAVA-Gson-格式化输出json字符串

作者: 瘦风(https://healchow.com)

出处: 博客园 瘦风的博客(https://www.cnblogs.com/shoufeng)

感谢阅读, 如果文章有帮助或启发到你, 点个[好文要顶👆] 或 [推荐👍] 吧😜

本文版权归博主所有, 欢迎转载, 但 [必须在文章页面明显位置标明原文链接], 否则博主保留追究相关人员法律责任的权利.