java中对象和json互转,java string json 转json对象

本文目录一览：

• 1、java中如何将对象转成json格式字符串
• 2、java对象怎么转json数组 跪求啊
• 3、java对象实体与json之间的转换

java中如何将对象转成json格式字符串

用Gson转换就行了，需要下载jar包

例子：

Person person=new Person();

Gson gson=new Gson();

String json=gson.toJson(person);

java对象怎么转json数组 跪求啊

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:

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]; }]

java对象实体与json之间的转换

我的object-json方法是自己实现的，其中可以对Long数组进行特殊处理，你代码中的JSONObject如果不便于修改的话，你可以把Long数组改成ListLong试试，如果不行只能自己扩展一下了