给一个合法的 json 字符串:
String origin = "{\"id\":123, \"name\": \"Bible\", \"writer\":{\"id\": 1234, \"name\": \"Tom\"}}";
origin 其实是一个 nested json object 。希望经过变换,把它拍平成:
String expected = "{\"id\":123, \"name\": \"Bible\", \"writer.id\":1234, \"writer.name\": \"Tom\"}";
大婶们不要吝啬