java集合或对象转化为json数组或者对象的方法

小灰灰 2022-06-09 04:48 204阅读 0赞

JSON-lib这个Java类包用于把bean,map和XML转换成JSON并能够把JSON转回成bean和DynaBean。  
  
下载地址:http://json-lib.sourceforge.net/  
还要需要的第3方包:  
org.apache.commons(3.2以上版本)  
org.apache.oro  
net.sf.ezmorph(ezmorph-1.0.4.jar)  
nu.xom  
  
1、List  
Java代码  
boolean\[\] boolArray =newboolean\[\]\{true,false,true\};  
JSONArray jsonArray1 = JSONArray.fromObject( boolArray );  
System.out.println( jsonArray1 );  
// prints \[true,false,true\]  
  
List list =newArrayList();  
list.add("first");  
list.add("second");  
JSONArray jsonArray2 = JSONArray.fromObject( list );  
System.out.println( jsonArray2 );  
// prints \["first","second"\]  
  
JSONArray jsonArray3 = JSONArray.fromObject("\['json','is','easy'\]");  
System.out.println( jsonArray3 );  
// prints \["json","is","easy"\]  
  
2、Map  
Java代码  
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 json = JSONObject.fromObject( map );  
System.out.println( json );  
//\{"func":function(i)\{ return this.arr\[i\]; \},"arr":\["a","b"\],"int":1,"name":"json","bool":true\}  
  
3、BEAN  
Java代码  
/\*\*  
\* Bean.java  
private String name = "json";  
private int pojoId = 1;  
private char\[\] ptions = new char\[\]\{'a','f'\};  
private String func1 = "function(i)\{ return this.options\[i\]; \}";  
private JSONFunction func2 = new JSONFunction(new String\[\]\{"i"\},"return this.options\[i\];");  
\*/  
JSONObject jsonObject = JSONObject.fromObject(newJsonBean() );  
System.out.println( jsonObject );  
//\{"func1":function(i)\{ return this.options\[i\]; \},"pojoId":1,"name":"json","options":\["a","f"\],"func2":function(i)\{ return this.options\[i\]; \}\}  
  
4、BEANS  
Java代码  
/\*\*  
\* private int row ;  
private int col ;  
private String value ;  
\*  
\*/  
List list =newArrayList();  
JsonBean2 jb1 =newJsonBean2();  
jb1.setCol(1);  
jb1.setRow(1);  
jb1.setValue("xx");  
  
JsonBean2 jb2 =newJsonBean2();  
jb2.setCol(2);  
jb2.setRow(2);  
jb2.setValue("");  
  
  
list.add(jb1);  
list.add(jb2);  
  
JSONArray ja = JSONArray.fromObject(list);  
System.out.println( ja.toString() );  
//\[\{"value":"xx","row":1,"col":1\},\{"value":"","row":2,"col":2\}\]  
  
5、String to bean  
Java代码  
String json ="\{name=\\"json\\",bool:true,int:1,double:2.2,func:function(a)\{ return a; \},array:\[1,2\]\}";  
JSONObject jsonObject = JSONObject.fromString(json);  
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") );  
List expected = JSONArray.toList( jsonObject.getJSONArray("array") );  
assertEquals( expected, (List) PropertyUtils.getProperty( bean,"array") );  
  
  
Java代码  
String json ="\{\\"value\\":\\"xx\\",\\"row\\":1,\\"col\\":1\}";  
JSONObject jsonObject = JSONObject.fromString(json);  
JsonBean2 bean = (JsonBean2) JSONObject.toBean( jsonObject, JsonBean2.class);  
assertEquals( jsonObject.get("col"),newInteger( bean.getCol()) );  
assertEquals( jsonObject.get("row"),newInteger( bean.getRow() ) );  
assertEquals( jsonObject.get("value"), bean.getValue() );  
  
  
6 json to xml  
1)  
JSONObject json = new JSONObject( true );  
String xml = XMLSerializer.write( json );  
  
<o class="object" null="true">  
  
2)  
JSONObject json = JSONObject.fromObject("\{\\"name\\":\\"json\\",\\"bool\\":true,\\"int\\":1\}");  
String xml = XMLSerializer.write( json );  
<o class="object">  
<name type="string">json</name>  
<bool type="boolean">true</bool>  
<int type="number">1</int>  
</o>  
<o class="object">  
<name type="string">json</name>  
<bool type="boolean">true</bool>  
<int type="number">1</int>  
</o>  
3)  
JSONArray json = JSONArray.fromObject("\[1,2,3\]");  
String xml = XMLSerializer.write( json );  
<a class="array">  
<e type="number">1</e>  
<e type="number">2</e>  
<e type="number">3</e>  
</a>  
  
7 、xml to json  
<a class="array">  
<e type="function" params="i,j">  
return matrix\[i\]\[j\];  
</e>  
</a>  
<a class="array">  
<e type="function" params="i,j">  
return matrix\[i\]\[j\];  
</e>  
</a>  
  
JSONArray json = (JSONArray) XMLSerializer.read( xml );  
System.out.println( json );  
// prints \[function(i,j)\{ return matrix\[i\]\[j\]; \}\]