Java: JSONObject.toJSONString output string content processing

Tip: After the article is written, the table of contents can be automatically generated. How to generate it can refer to the help document on the right

---

foreword

JSONObject can convert Java objects into JSON stream output, which is very useful for data display or data interaction.

However, the string output by JSONObject.toJSONString often has the following format problems:
1. The String type in Java contains double quotation marks ("") when outputting.
2. The Date type in Java is output as milliseconds (that is, a string Number)
3. When the JSON stream is output, it contains square brackets ("[" "]") by default.
4. The value in Java is empty, and when the JSON stream is output, it is null

This paper presents solutions to these problems.

---

1. Remove the double quotes in the JSON string

Use String.replaceAll() to remove

Key point: use the escape character \

Code example:

JSONObject.toJSONString(output).replaceAll("\"","")

2. When the Date type is output, follow the standard time format

Use: JSONObject.toJSONStringWithDateFormat()

Key point: the time format can be freely defined as needed

Code example:

JSONObject.toJSONStringWithDateFormat(out,"yyyy-MM-dd HH:mm:ss");

3. Remove the default square brackets before and after the JSON stream output

Use String.replace() to remove

JSONObject.toJSONString(out).replace("[","").replace("]","");

4. Remove the nulls that may be contained in the JSON stream output

Or use String.replace() to remove

JSONObject.toJSONString(out).replace("null","");

Summary, JSON output conforms to the conventional format and does not contain null content

JSONObject.toJSONStringWithDateFormat(out,"yyyy-MM-dd HH:mm:ss").replaceAll("\"","").replace("[","").replace("]","").replace("null","");

---

write at the end

When JSONObject.toJSONString outputs, it actually outputs a string, and you can use String.replaceAll() to remove any content that you don’t want to see.

The methods introduced in this article are actually stupid methods. You can also use character regular expressions to match , and then remove them according to your needs.
Using character regular expressions to match the code will be much more concise and capable. Friends who are interested can study it.

hope its good for U.S!