格式化JSON——fastjson

SerializerFeature的个别属性

名称	含义
QuoteFieldNames	输出key时是否使用双引号,默认为true
UseSingleQuotes	使用单引号而不是双引号,默认为false
WriteMapNullValue	是否输出值为null的字段,默认为false
PrettyFormat	结果是否格式化,默认为false
SortField	按字段名称排序后输出。默认为false

示例：

public static void main(String[] args) throws InvocationTargetException, IllegalAccessException {
    String str = "{\"id\": 1,\"name\": \"张三\",\"child\": [{\"id\": 11,\"name\": \"李四\",\"child\": [],\"age\": 40},{\"id\": 12,\"name\": \"老六\",\"child\": [{\"id\": 21,\"name\": \"小六\",\"age\": 14,\"child\":[{\"id\":41,\"name\":null,\"child\":null,\"age\":0}]}],\"age\": 36}],\"age\": 80}";
    JSONObject jsonObject = JSONObject.parseObject(str);
    String pretty = JSON.toJSONString(jsonObject, SerializerFeature.PrettyFormat, SerializerFeature.WriteMapNullValue);
    System.out.println(pretty);
}

输出结果：

{
	"name":"张三",
	"id":1,
	"age":80,
	"child":[
		{
			"name":"李四",
			"id":11,
			"age":40,
			"child":[]
		},
		{
			"name":"老六",
			"id":12,
			"age":36,
			"child":[
				{
					"name":"小六",
					"id":21,
					"age":14,
					"child":[
						{
							"id":41,
							"age":0
						}
					]
				}
			]
		}
	]
}