Convert between Java and json objects
- 2020-04-01 03:01:57
- OfStack
Json-lib is a Java library that provides the ability to convert Java objects, including beans, maps, collections, Java arrays and XML, into json or vice versa.
2. The json - lib homepage: http://json-lib.sourceforge.net/
3. Execution environment
The following class library support is required
Commons lang - 2.5
Commons - beanutils 1.8.0 comes with
The Commons - the collections 3.2.1
Commons - logging 1.1.1
Ezmorph 1.0.6
4. Functional examples
Here is a code example with a junit-case example
package com.mai.json;
import static org.junit.Assert.assertEquals;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import net.sf.ezmorph.Morpher;
import net.sf.ezmorph.MorpherRegistry;
import net.sf.ezmorph.bean.BeanMorpher;
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
import net.sf.json.util.JSONUtils;
import org.apache.commons.beanutils.PropertyUtils;
import org.junit.Test;
public class JsonLibTest {
/*
* General type, List , Collection Is used JSONArray parsing
*
* Map , custom types are used JSONObject parsing
* Can be Map Understood as an object, inside key/value Properties that can be understood as objects / Attribute values
* namely {key1:value1,key2,value2......}
*
* 1.JSONObject Is a name:values Set through it get(key) The method gets this key After the corresponding value Part of the ( string )
* Through its getJSONObject(key) I can take one JSONObject . --> Converted to map,
* Through its getJSONArray(key) I can take one JSONArray .
*
*
*/
//Normally an array is converted to JSON
@Test
public void testArrayToJSON(){
boolean[] boolArray = new boolean[]{true,false,true};
JSONArray jsonArray = JSONArray.fromObject( boolArray );
System.out.println( jsonArray );
// prints [true,false,true]
}
//Convert the Collection object to JSON
@Test
public void testListToJSON(){
List list = new ArrayList();
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, using JSONArray or JSONObject, as the case may be
@Test
public void testJsonStrToJSON(){
JSONArray jsonArray = JSONArray.fromObject( "['json','is','easy']" );
System.out.println( jsonArray );
// prints ["json","is","easy"]
}
//Map is converted to json using jsonObject
@Test
public void testMapToJSON(){
Map map = new HashMap();
map.put( "name", "json" );
map.put( "bool", Boolean.TRUE );
map.put( "int", new Integer(1) );
map.put( "arr", new String[]{"a","b"} );
map.put( "func", "function(i){ return this.arr[i]; }" );
JSONObject jsonObject = JSONObject.fromObject( map );
System.out.println( jsonObject );
}
//The composite bean is converted to json
@Test
public void testBeadToJSON(){
MyBean bean = new MyBean();
bean.setId("001");
bean.setName(" Bank card ");
bean.setDate(new Date());
List cardNum = new ArrayList();
cardNum.add(" The ABC ");
cardNum.add(" icbc ");
cardNum.add(" The construction bank ");
cardNum.add(new Person("test"));
bean.setCardNum(cardNum);
JSONObject jsonObject = JSONObject.fromObject(bean);
System.out.println(jsonObject);
}
//Json of normal type is converted to objects
@Test
public void testJSONToObject() throws Exception{
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);
}
}
//Parse the json into a composite type object that contains the List
@Test
public void testJSONToBeanHavaList(){
String json = "{list:[{name:'test1'},{name:'test2'}],map:{test1:{name:'test1'},test2:{name:'test2'}}}";
// String json = "{list:[{name:'test1'},{name:'test2'}]}";
Map classMap = new HashMap();
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(o instanceof Person){
Person p = (Person)o;
System.out.println(p.getName());
}
}
}
//Parse the json into a composite type object, including a Map
@Test
public void testJSONToBeanHavaMap(){
//Think of a Map as an object
String json = "{list:[{name:'test1'},{name:'test2'}],map:{testOne:{name:'test1'},testTwo:{name:'test2'}}}";
Map classMap = new HashMap();
classMap.put("list", Person.class);
classMap.put("map", Map.class);
//Using hinting, the json is directly parsed into the specified custom object, where the List is fully parsed and the Map is not
MyBeanWithPerson 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 first, you need to use the classes in the ezmorph package
MorpherRegistry morpherRegistry = JSONUtils.getMorpherRegistry();
Morpher dynaMorpher = new BeanMorpher( Person.class, morpherRegistry);
morpherRegistry.registerMorpher( dynaMorpher );
Map map = diyBean.getMap();
System.out.println(map);
List<Person> output = new ArrayList();
for( Iterator i = map.values().iterator(); i.hasNext(); ){
//The specified DynaBean is transformed using the registry
output.add( (Person)morpherRegistry.morph( Person.class, i.next() ) );
}
for(Person p : output){
System.out.println(p.getName());
}
}
}
5. The resources required for the above example, including jars and code, are provided below
/Files/mailingfeng/json-lib/json-lib use case required jar package and Java class. Rar