Using Json-lib to convert between Java and JSON

Source: Internet
Author: User
Tags object object

1. Json-lib is a Java class library that provides the ability to convert Java objects, including beans, maps, collections, Java Arrays and XML, to JSON, or reverse-transform.

2. Json-lib Home: http://json-lib.sourceforge.net/

3. Execution Environment

The following class library support is required

    • Jakarta Commons-lang 2.5
    • Jakarta commons-beanutils 1.8.0
    • Jakarta commons-collections 3.2.1
    • Jakarta commons-logging 1.1.1
    • Ezmorph 1.0.6

4. Feature examples

The code example is given here through the junit-case example

 PackageCom.mai.json;Import Staticorg.junit.Assert.assertEquals;Importjava.util.ArrayList;Importjava.util.Date;ImportJava.util.HashMap;ImportJava.util.Iterator;Importjava.util.List;ImportJava.util.Map;ImportNet.sf.ezmorph.Morpher;ImportNet.sf.ezmorph.MorpherRegistry;ImportNet.sf.ezmorph.bean.BeanMorpher;ImportNet.sf.json.JSONArray;ImportNet.sf.json.JSONObject;Importnet.sf.json.util.JSONUtils;Importorg.apache.commons.beanutils.PropertyUtils;Importorg.junit.Test; Public classJsonlibtest {/** Common Type, List, collection, etc. are resolved with Jsonarray * map, custom type is resolved with Jsonobject * Map can be understood as an object, the Key/value of the inside can be     To understand the property/property value of an object * that is {key1:value1,key2,value2 ...} * * 1.JSONObject is a name:values collection, obtained through its get (key) method is key after the corresponding value part (string) * through its getjsonobject (key) can be taken to a jsonobject,- ---Convert to map, * through its getjsonarray (key) can be taken to a jsonarray, * **/        //general arrays converted to JSON@Test Public voidTestarraytojson () {Boolean[] Boolarray =New Boolean[]{true,false,true}; Jsonarray Jsonarray=Jsonarray.fromobject (Boolarray);          System.out.println (Jsonarray); //prints [true,false,true]    }            //collection objects into JSON@Test Public voidTestlisttojson () {List List=NewArrayList (); List.add ("First" ); List.add ("Second" ); Jsonarray Jsonarray=jsonarray.fromobject (list);          System.out.println (Jsonarray); //prints ["First", "second"]    }            //the string JSON is converted to JSON, as the case may be with Jsonarray or Jsonobject@Test Public voidTestjsonstrtojson () {Jsonarray Jsonarray= Jsonarray.fromobject ("[' json ', ' is ', ' easy ']" );          System.out.println (Jsonarray); //prints ["JSON", "is", "easy"]    }            //The map is converted to JSON, using Jsonobject@Test Public voidTestmaptojson () {map map=NewHashMap (); Map.put ("Name", "JSON" ); Map.put ("BOOL", boolean.true); Map.put ("Int",NewInteger (1) ); Map.put ("Arr",NewString[]{"A", "B"} ); Map.put ("Func", "function (i) {return this.arr[i];}" ); Jsonobject Jsonobject=jsonobject.fromobject (map);      System.out.println (Jsonobject); }        //compound type bean turns into JSON@Test Public voidTestbeadtojson () {Mybean bean=NewMybean (); Bean.setid ("001"); Bean.setname ("Bank card"); Bean.setdate (NewDate ()); List Cardnum=NewArrayList (); Cardnum.add (Agricultural Bank); Cardnum.add (Icbc); Cardnum.add (Ccb); Cardnum.add (NewPerson ("test"));                Bean.setcardnum (Cardnum); Jsonobject Jsonobject=Jsonobject.fromobject (Bean);            System.out.println (Jsonobject); }        //normal types of JSON are converted into objects@Test Public voidTestjsontoobject ()throwsexception{String JSON= "{name=\" json\ ", Bool:true,int:1,double:2.2,func:function (a) {return A;},array:[1,2]}"; Jsonobject Jsonobject=Jsonobject.fromobject (JSON);        System.out.println (Jsonobject); Object Bean=Jsonobject.tobean (Jsonobject); Assertequals (Jsonobject.get ("Name"), Propertyutils.getproperty (Bean, "name") ) ); Assertequals (Jsonobject.get ("bool"), Propertyutils.getproperty (Bean, "bool") ) ); Assertequals (Jsonobject.get ("int"), Propertyutils.getproperty (Bean, "int") ) ); Assertequals (Jsonobject.get ("Double"), Propertyutils.getproperty (Bean, "double") ) ); Assertequals (Jsonobject.get ("Func"), Propertyutils.getproperty (Bean, "func") ) ); System.out.println (Propertyutils.getproperty (Bean,"Name")); System.out.println (Propertyutils.getproperty (Bean,"BOOL")); System.out.println (Propertyutils.getproperty (Bean,"Int")); System.out.println (Propertyutils.getproperty (Bean,"Double")); System.out.println (Propertyutils.getproperty (Bean,"Func")); System.out.println (Propertyutils.getproperty (Bean,"Array")); List arrayList= (List) jsonarray.tocollection (Jsonobject.getjsonarray ("array"));  for(Object object:arraylist) {System.out.println (object); }            }            //parses the JSON into a composite type object that contains the list@Test Public voidtestjsontobeanhavalist () {String json= "{list:[{name: ' test1 '},{name: ' Test2 '}],
Map:{test1:{name: ' test1 '},test2:{name: ' Test2 '}} ';//String json = "{list:[{name: ' test1 '},{name: ' Test2 '}]}";Map Classmap =NewHashMap (); Classmap.put ("List", person.class); Mybeanwithperson Diybean= (Mybeanwithperson) Jsonobject.tobean (Jsonobject.fromobject (JSON), Mybeanwithperson.class, Classmap); System.out.println (Diybean); List List=diybean.getlist (); for(Object o:list) {if(OinstanceofPerson ) {Person P=(person) o; System.out.println (P.getname ()); } } } //parses the JSON into a composite type object that contains the map@Test Public voidTestjsontobeanhavamap () {//think of map as an objectString json = "{list:[{name: ' test1 '},{name: ' test2 '}],map:{testone:{name: ' test1 '},testtwo:{name: ' Test2 '}}"; Map Classmap=NewHashMap (); Classmap.put ("List", person.class); Classmap.put ("Map", map.class); //use the hint to parse the JSON directly into the specified custom object, where list is fully parsed and map is not fully parsedMybeanwithperson Diybean = (Mybeanwithperson) Jsonobject.tobean (Jsonobject.fromobject (JSON), MyBeanWithPerson.class, Classmap); System.out.println (Diybean); System.out.println ("Do the list release"); List<Person> list =diybean.getlist (); for(person o:list) {person P=(person) o; System.out.println (P.getname ()); } System.out.println ("Do the map release"); //To register the converter in the Registrar, you need to use the class in the Ezmorph packageMorpherregistry Morpherregistry =Jsonutils.getmorpherregistry (); Morpher Dynamorpher=NewBeanmorpher (person.class, Morpherregistry); Morpherregistry.registermorpher (Dynamorpher); Map Map=Diybean.getmap (); /*The map here does not have a type hint, so by default, the object stored as Net.sf.ezmorph.bean.MorphDynaBean type*/System.out.println (map); /*output: {[email protected][{name=test1}], [email protected][{name=test2}]} */List<Person> output =NewArrayList (); for(Iterator i =map.values (). iterator (); I.hasnext ();) { //using the Registrar to transform the specified Dynabean objectOutput.add (person) morpherregistry.morph.class, I.next ())); } for(person P:output) {System.out.println (P.getname ()); /*output: test1 test2*/ } } } 5the resources required for the above example are provided below, including the jar package and the code/files/mailingfeng/json-lib/json-lib jar Packages and Java classes required for use cases. rar

Using Json-lib to convert between Java and JSON

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