JSON是一種很簡潔很重要的數據格式,通常用來交換傳輸數據,廣泛使用於JavaScript技術中,並逐漸在各種流行編程語言中火了起來.
在Java中也有一個JSON的庫,用來重要作用就是Java對象與JSON、XML數據的相互轉換,有著重要的應用.
開源的JSON庫主頁：http://json-lib.sourceforge.net/
本開源項目的文檔非常好,一下是我看快速起步文檔所寫,原快速上手文檔有一些錯誤和問題,這裡都處理過了.
環境：
JDK5
json-lib-2.3-jdk15
測試所依賴的包：
json-lib-2.3-jdk15.jar
commons-collections.jar
commons-lang.jar
commons-logging.jar
commons-beanutils.jar
ezmorph-1.0.6.jar
xom-1.1.jar
測試代碼：
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
import net.sf.json.xml.XMLSerializer;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* JSON for Java測試代碼
*
* @author leizhimin 2009-12-28 13:15:25
*/
public class TestJSON {
public static void main(String[] args) {
test1();
test2();
test3();
test4();
test5();
}
/**
* 數組或集合-->JSON串
*/
public static void test1() {
System.out.println("------------數組或集合-->JSON串----------");
boolean[] boolArray = new boolean[]{true, false, true};
JSONArray jsonArray1 = JSONArray.fromObject(boolArray);
System.out.println(jsonArray1);
//[true,false,true]
List list = new ArrayList();
list.add("first");
list.add("second");
JSONArray jsonArray2 = JSONArray.fromObject(list);
System.out.println(jsonArray2);
//["first","second"]
JSONArray jsonArray3 = JSONArray.fromObject("['json','is','easy']");
System.out.println(jsonArray3);
// ["json","is","easy"]
}
/**
* Object|Map-->JSON串
*/
public static void test2() {
System.out.println("------------Object|Map-->JSON串----------");
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 jsonObject1 = JSONObject.fromObject(map);
System.out.println(jsonObject1);
//{"func":function(i){ return this.arr[i]; },"arr":["a","b"],"int":1,"bool":true,"name":"json"}
JSONObject jsonObject2 = JSONObject.fromObject(new MyBean());
System.out.println(jsonObject2);
//{"func1":function(i){ return this.options[i]; },"func2":function(i){ return this.options[i]; },"name":"json","options":["a","f"],"pojoId":1}
}
/**
* JSON串-->Object
*/
public static void test3() {
System.out.println("------------JSON串-->Object----------");
String json1 = "{name="json",bool:true,int:1,double:2.2,func:function(a){ return a; },array:[1,2]}";
JSONObject jsonObject1 = JSONObject.fromObject(json1);
Object bean1 = JSONObject.toBean(jsonObject1);
System.out.println(bean1);
//net.sf.ezmorph.bean.MorphDynaBean@10dd1f7[
// {double=2.2, func=function(a){ return a; }, int=1, name=json, bool=true, array=[1, 2]}
//]
String json2 = "{bool:true,integer:1,string:"json"}";
JSONObject jsonObject2 = JSONObject.fromObject(json2);
BeanA bean2 = (BeanA) JSONObject.toBean(jsonObject2, BeanA.class);
System.out.println(bean2);
// BeanA{bool=true, integer=1, string='json'}
}
/**
* JSON串-->XML
*/
public static void test4() {
System.out.println("------------JSON串-->XML----------");
JSONObject json = new JSONObject(true);
String xml = new XMLSerializer().write(json);
System.out.println(xml);
JSONObject json1 = JSONObject.fromObject("{"name":"json","bool":true,"int":1}");
String xml1 = new XMLSerializer().write(json1);
System.out.println(xml1);
JSONArray json2 = JSONArray.fromObject("[1,2,3]");
String xml2 = new XMLSerializer().write(json2);
System.out.println(xml2);
}
/**
* XML-->JSON串
*/
public static void test5() {
System.out.println("------------XML-->JSON串----------");
String xml = ""
"<a class="array">n"
" <e type="function" params="i,j">n"
" return matrix[i][j];n"
" </e>n"
"</a>";
JSONArray json = (JSONArray) new XMLSerializer().read(xml);
System.out.println(json);
}
}
import net.sf.json.JSONFunction;
/**
* 測試Bean
*
* @author leizhimin 2009-12-28 13:55:09
*/
public class MyBean {
private String name = "json";
private int pojoId = 1;
private char[] options = new char[]{'a', 'f'};
private String func1 = "function(i){ return this.options[i]; }";
private JSONFunction func2 = new JSONFunction(new String[]{"i"}, "return this.options[i];");
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getPojoId() {
return pojoId;
}
public void setPojoId(int pojoId) {
this.pojoId = pojoId;
}
public char[] getOptions() {
return options;
}
public void setOptions(char[] options) {
this.options = options;
}
public String getFunc1() {
return func1;
}
public void setFunc1(String func1) {
this.func1 = func1;
}
public JSONFunction getFunc2() {
return func2;
}
public void setFunc2(JSONFunction func2) {
this.func2 = func2;
}
}
/**
* 測試Bean
*
* @author leizhimin 2009-12-28 14:18:18
*/
public class BeanA {
// String json2 = "{bool:true,integer:1,string:"json"}";
private boolean bool;
private Integer integer;
private String string;
public boolean isBool() {
return bool;
}
public void setBool(boolean bool) {
this.bool = bool;
}
public Integer getInteger() {
return integer;
}
public void setInteger(Integer integer) {
this.integer = integer;
}
public String getString() {
return string;
}
public void setString(String string) {
this.string = string;
}
@Override
public String toString() {
return "BeanA{"
"bool=" bool
", integer=" integer
", string='" string '''
'}';
}
}
運行結果：
------------數組或集合-->JSON串----------
[true,false,true]
["first","second"]
["json","is","easy"]
------------Object|Map-->JSON串----------
{"func":function(i){ return this.arr[i]; },"arr":["a","b"],"int":1,"bool":true,"name":"json"}
{"func1":function(i){ return this.options[i]; },"func2":function(i){ return this.options[i]; },"name":"json","options":["a","f"],"pojoId":1}
------------JSON串-->Object----------
net.sf.ezmorph.bean.MorphDynaBean@bd0108[
{double=2.2, func=function(a){ return a; }, int=1, name=json, bool=true, array=[1, 2]}
]
BeanA{bool=true, integer=1, string='json'}
------------JSON串-->XML----------
<?xml version="1.0" encoding="UTF-8"?>
<o null="true"/>
<?xml version="1.0" encoding="UTF-8"?>
<o><bool type="boolean">true</bool><int type="number">1</int><name type="string">json</name></o>
<?xml version="1.0" encoding="UTF-8"?>
<a><e type="number">1</e><e type="number">2</e><e type="number">3</e></a>
------------XML-->JSON串----------
2009-12-28 15:20:39 net.sf.json.xml.XMLSerializer getType
信息: Using default type string
[function(i,j){ return matrix[i][j]; }]
Process finished with exit code 0
特別注意：
1、所有的Bean都應該定義為public,否則會出現
net.sf.json.JSONException: java.lang.NoSuchMethodException: Property '***' has no getter method
的錯誤.
2、必須引入xom-1.1.jar包,否則拋出
java.lang.NoClassDefFoundError: nu/xom/Serializer
的異常.
另外,還有個開源的JSON庫,推薦下：
http://code.google.com/p/google-gson/
本文出自 「熔 岩」 博客,請務必保留此出處http://lavasoft.blog.51cto.com/62575/251179
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