JSONObject basic content (1), JSONObject content (

JSONObject basic content (1), JSONObject content (

Reference: http://swiftlet.net/archives/category/json. Thank you very much ~

 

It is not difficult to use a json object when you are working on a project. However, if you are not using it for a long time, you will forget it. So write down its basic usage.

 

Prerequisites: import related jar files:

Commons-lang-1.0.4.jar
Commons-collections-2.1.jar
Commons-beanutils-1.8.0.jar
Json-lib-2.4.jar
Ezmorph-1.0.6.jar
Commons-logging-1.1.jar

 

Then you can develop it ~

 

1) convert javaBean to json

(1) Write A javaBean

　　

public class User  implements Serializable{    private static final long serialVersionUID = 1L;        private String username;    private String password;    public String getUsername() {        return username;    }    public void setUsername(String username) {        this.username = username;    }    public String getPassword() {        return password;    }    public void setPassword(String password) {        this.password = password;    }    }

Then convert the javaBean to JSONObject:

Public static void main (String [] args) {// convert the an object to the json String User user = new User (); user. setUsername ("Rime"); user. setPassword ("1234"); JSONObject json1 = JSONObject. fromObject (user); System. out. println (json1.toString (); // map is converted to the json string HashMap <Object, Object> userMap = new HashMap <Object, Object> (); userMap. put ("username", "Rime"); userMap. put ("password", "1234"); JSONObject json2 = JSONObject. fromObject (userMap); System. out. println (json2.toString ());}

The output content is as follows:

{"Password": "1234", "username": "Rime "}
{"Username": "Rime", "password": "1234 "}

 

Here, you may wonder if any object can be converted to JSONObject? Of course, the answer is: no.

The JSONObject. fromObject (Object object) method is only valid for objects of the following type in the Set: JSON formatted strings, Maps, DynaBeans and JavaBeans.

[Note] DynaBeans is a dynamic bean defined by commons-beanutils. DynaBean is not a Bean defined in Java, but a "fake" Bean. Because it does not use the getXXX and setXXX methods to set and set values for the XXX attribute.
What if the object is a parameter of another type? For example, numbers, logical values, and strings in non-json format will produce empty JSONObject objects.