Json-lib use

• Json-lib

Json-lib is a Java class library (official website: http://json-lib.sourceforge.net/) to achieve the following functions:

• Convert JavaBeans, maps, collections, Java arrays, and XML into JSON format data
• Convert JSON format data to a JavaBeans object

Json-lib Required JAR Package

• Commons-beanutils-1.8.3.jar
• Commons-collections-3.2.1.jar
• Commons-lang-2.6.jar
• Commons-logging-1.1.1.jar
• Ezmorph-1.0.6.jar
• Json-lib-2.4-jdk15.jar

• Use of Json-lib

1. Parse the Array into a Json string.

@Test
public void Arrtojson () {
/**
* Convert array to JSON string
*/
string[] str = {"Json", "Json-lib", "Jackson", "Xml"};
Jsonarray JSON = Jsonarray.fromobject (str);
SYSTEM.OUT.PRINTLN (JSON);

/**
* Object array to JSON
*/
Person[] ps = {new person (1, "slight", false, New Date (), Arrays.aslist (new string[] {"Play", "Game", "Anime"}),
New Person (2, "haha", false, New Date (), Arrays.aslist (new string[] {"Play"}))
};
JSON = Jsonarray.fromobject (PS);
SYSTEM.OUT.PRINTLN (JSON);

/**
* Convert List collection to JSON
*/
list<person> plist = new arraylist<person> ();
Plist.add (New person (1, "slight", false, New Date (), Arrays.aslist (new string[] {"Play", "Game", "Anime"}));
Plist.add (New person (2, "haha", false, New Date (), Arrays.aslist (new string[] {"Play"}));
JSON = Jsonarray.fromobject (PS);
SYSTEM.OUT.PRINTLN (JSON);

}

The results of the operation are as follows:

["Json", "Json-lib", "Jackson", "Xml"]
[{"Birthday": {"date": +, "Day": 5, "hours": +, "minutes": +, "month": 3, "Seconds": "," "Time": 1492169396320, " Timezoneoffset ": -480," Year ": 117}," Gender ": false," hobby ": [" Play "," Game "," Anime "]," id ": 1," name ":" Slightly "},{" birthday ": {" Date ":" Day ": 5," hours ": +," minutes ":" Month ": 3," Seconds ":" "," "Time: 1492169396320," Timezoneoffset ":-480," Year ": 117}," Gender ": false," hobby ": [" Play "]," id ": 2," name ":" Haha "}]
[{"Birthday": {"date": +, "Day": 5, "hours": +, "minutes": +, "month": 3, "Seconds": "," "Time": 1492169396320, " Timezoneoffset ": -480," Year ": 117}," Gender ": false," hobby ": [" Play "," Game "," Anime "]," id ": 1," name ":" Slightly "},{" birthday ": {" Date ":" Day ": 5," hours ": +," minutes ":" Month ": 3," Seconds ":" "," "Time: 1492169396320," Timezoneoffset ":-480," Year ": 117}," Gender ": false," hobby ": [" Play "]," id ": 2," name ":" Haha "}]

2. Parse the Javabean/map into a JSON string. Using Jsonobject parsing:

@Test
public void Beantojson () {

/**
* Convert objects to JSON
*/
Person p = new person (1, "slight", false, New Date (), Arrays.aslist (new string[] {"Play", "Game", "Anime"}));
Jsonobject json = Jsonobject.fromobject (p);
SYSTEM.OUT.PRINTLN (JSON);

/**
* Parse Map
*/
map<string, object> map = new hashmap<string, object> ();
Map.put ("name", "Director III");
Map.put ("Age", 24);
JSON = Jsonobject.fromobject (map);
SYSTEM.OUT.PRINTLN (JSON);

}

The results of the operation are as follows:

{"Birthday": {"date": +, "Day": 5, "hours": +, "minutes": +, "month": 3, "Seconds": "Time": 1492169902753, " Timezoneoffset ": -480," Year ": 117}," Gender ": false," hobby ": [" Play "," Game "," Anime "]," id ": 1," name ":" Slightly "}
{"Age": +, "name": "Director Three"}

3. Using the Jsonconfig-over property: for Javabean/map

@Test
public void Jsonconfig () {
/**
* Filter Properties using Jsonconfig
*/
Person p = new person (1, "slight", false, New Date (), Arrays.aslist (new string[] {"Play", "Game", "Anime"}));
Jsonconfig config = new Jsonconfig ();
Config.setexcludes (new string[] {"Birthday"});
Jsonobject json = jsonobject.fromobject (P, config);
SYSTEM.OUT.PRINTLN (JSON);
}

The result of the operation is as follows, and we can see that the name attribute is filtered out in the running result:

{"Gender": false, "hobby": ["Play", "Game", "Anime"], "id": 1, "name": "Slightly"}

4. Convert the Json string to an Array:

@Test
public void Jsontoarr () {

/**
* JSON converted to a generic array
*/
string[] str = {"Json", "Json-lib", "Jackson", "Xml"};
Jsonarray JSON = Jsonarray.fromobject (str);

Object STRs = Jsonarray.toarray (JSON);
System.out.println (STRs);
System.out.println (Arrays.aslist ((object[)) STRs);

list<person> plist = new arraylist<person> ();
Plist.add (New person (1, "slight", false, New Date (), Arrays.aslist (new string[] {"Play", "Game", "Anime"}));
Plist.add (New person (2, "haha", false, New Date (), Arrays.aslist (new string[] {"Play"}));
JSON = Jsonarray.fromobject (plist);

list<person> PS = (list<person>) jsonarray.tocollection (JSON, person.class);
for (person Person:ps) {
SYSTEM.OUT.PRINTLN (person);
}
}

The results of the operation are as follows:

[ljava.lang.object;@39e87719
[Json, Json-lib, Jackson, Xml]
person [id=1, Name=, Gender=false, Birthday=fri Apr 20:18:29 CST, hobby=[play, game, anime]]
person [id=2, name= haha, gender=false, Birthday=fri Apr 20:18:29 CST, hobby=[Play]]

5. Turn the Json string into JavaBean:

@Test
public void Jsontobean () {
/**
* JSON converted to JavaBean
*/
Person p = new person (1, "slight", false, New Date (), Arrays.aslist (new string[] {"Play", "Game", "Anime"}));
Jsonobject json = Jsonobject.fromobject (p);

Object o = Jsonobject.tobean (JSON, person.class);
System.out.println (o);



}

The results of the operation are as follows:

2017-4-14 20:19:51 Net.sf.json.JSONObject Tobean
Info: Property ' Day ' of class java.util.Date has no write method. Skipped.
2017-4-14 20:19:51 Net.sf.json.JSONObject Tobean
Information: Property ' Timezoneoffset ' of class java.util.Date have no write method. Skipped.
person [id=1, Name=, Gender=false, Birthday=fri Apr 20:19:51 CST, hobby=[play, game, anime]]

When converting a Json-like string to JavaBean, it is important to note that there must be no parameter constructor in the JavaBean, or the following error cannot be found for the initialization method:

Exception in thread "main" Net.sf.json.jsonexception:java.lang.nosuchmethodexception:cn.sunzn.json.person.<init > () at   Net.sf.json.JSONObject.toBean (jsonobject.java:288) at   Net.sf.json.JSONObject.toBean ( jsonobject.java:233) at   Cn.sunzn.json.JsonLib.main (jsonlib.java:23) caused by:java.lang.NoSuchMethodException : Cn.sunzn.json.person.<init> () at   java.lang.Class.getConstructor0 (Unknown Source)   at Java.lang.Class.getDeclaredConstructor (Unknown Source) at   net.sf.json.util.newbeaninstancestrategy$ Defaultnewbeaninstancestrategy.newinstance (newbeaninstancestrategy.java:55) at   Net.sf.json.JSONObject.toBean (jsonobject.java:282) ...   2 more

Json-lib use