Then think about is not so resolved , this can only see the results , but can not handle the result set.
so you had to json format into javaBean can.
then looked at the statistics , the largest online information this way is the following :
String str = "[{\"id\":\"\",\"num\":\"\",\"dt\":\"2010-07-21T17:29:28\",\"consignee\":\"aaaa\",\"bank\":\"001\",\"ems\":\"0\"}]";
JSONArray array = JSONArray.fromObject(str);//先读取串数组
Object[] o = array.toArray(); //转成对像数组
System.err.println(o.length);
JSONObject obj = JSONObject.fromObject(o[0]);//再使用JsonObject遍历一个个的对像
Order oo = (Order)obj.toBean(obj,Order.class);//指定转换的类型，但仍需要强制转化-成功
System.err.println(oo.getDt()+","+oo.getConsignee());
String ss = oo.getDt();
need jar package is : json-lib
But Jingdong provided inside a jar I did not find the required classes. ( Do not want to add additional jar package )
So keep looking , finally found a ObjectMapper
continue online search usage example of this class have , but relatively small, there is no direct can readily use.
So he began to try various ways to do their own examples .
end up spending two hours and finally try out a simple little example. And share with you , big hands who do not spray ! ~
First string:
String str="{\"student\":[{\"name\":\"leilei\",\"age\":23},{\"name\":\"leilei02\",\"age\":23}]}"; Next, create a class StudentList
public class StudentList {
List<Student> student;
public List<Student> getStudent() {
return student;
}
public void setStudent(List<Student> student) {
this.student = student;
}
}
Here is the Student class
public class Student {
private String name;
private int age;
//private StudentClass studentClass;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
} final test program
import java.util.List;
import org.codehaus.jackson.map.ObjectMapper;
public class JsonToJavaBean {
public static void main(String[] args) {
String str="{\"student\":[{\"name\":\"leilei\",\"age\":23},{\"name\":\"leilei02\",\"age\":23}]}";
Student stu = null;
List<Student> list = null;
try {
ObjectMapper objectMapper=new ObjectMapper();
StudentList studentList=objectMapper.readValue(str, StudentList.class);
list=studentList.getStudent();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
for(Student s:list){
System.out.println(s.getName());
}
}
Results:
leilei
leilei02
success. . Excitement ing! ~
continue to try to add in the student inside the class attribute methods
Class stuclass {
private int classid;
private int gradeid;
}
------ Solution ----------------------------------- ---------
online there are many such third-party packages.
------ Solution ---------------------------------------- ----
- ----- Solution -------------------------------------------- which is exactly
jar package have ?
jackson-mapper-asl-1.0.0.jar
jackson-mapper-lgpl-1.0.0.jar
------ Solution ------------------------------------ --------
tools with Google 's Gson easier
------ Solution --------------------- -----------------------
flexjson also good
------ For reference only --------- ------------------------------
I know that there are many such jar package ah , this example is in fact jar package is for these applications only.
------ For reference only -------------------------------------- -
import org.codehaus.jackson.map.ObjectMapper;
jar package : jackson-core-asl-1.8.1.jar
------ For reference only -------------------- -------------------
------ For reference only ---------------------------------- -----
landlord , I think you built StudentList class did their role , directly accept data when using the List
----- - For reference only ---------------------------------------
just works using that learned
------ For reference only ---------------------------------- -----
then ask you, how can dynamically generate String str = "{\" student \ ": [{\" name \ ": \" leilei \ " ;, \ "age \": 23}, {\ "name \": \ "leilei02 \", \ "age \": 23}]} "; this inlay sets format json object it ?
------ For reference only ---------------------------------- -----
Google GSON easily get
------ For reference only -------------------------- -------------
encountered the same problem , the landlord or remove json that you need to add a third-party jar, is not particularly desirable , but no way to find a better solution
------ For reference only ---------------------------------------
did not know there is such a third-party package , so I wrote one , in fact, quite simple
------ For reference only --------------- ------------------------
paste code for your reference
package cn.qtone.mobile.utils;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
/ **
* the JSON data into a concrete object
* @ author jqp
*
* /
public class JsonUtil {
public static
if (jsonObject == null) return null;
Field [] fb = cla.getDeclaredFields ();
T t;
try {
t = cla.newInstance ();
for (int j = 0; j
String fieldNameU = fieldName.substring (0, 1). toUpperCase () + fieldName.substring (1);
Method method = cla.getMethod ("set" + fieldNameU, fb [j]. getType ());
method.invoke (t, jsonObject.get (fieldName));
}
return t;
} catch (SecurityException e) {
/ / TODO Auto-generated catch block
e.printStackTrace ();
} catch (IllegalArgumentException e) {
/ / TODO Auto-generated catch block
e.printStackTrace ();
} catch (IllegalAccessException e) {
/ / TODO Auto-generated catch block
e.printStackTrace ();
} catch (InstantiationException e) {
/ / TODO Auto-generated catch block
e.printStackTrace ();
} catch (NoSuchMethodException e) {
/ / TODO Auto-generated catch block
e.printStackTrace ();
} catch (InvocationTargetException e) {
/ / TODO Auto-generated catch block
e.printStackTrace ();
} catch (JSONException e) {
/ / TODO Auto-generated catch block
e.printStackTrace ();
}
return null;
}
public static
List
if (jsonArray == null) return list;
try {
for (int i = 0; i
T t = JsonUtil.convertToObj (jsonObject, cla) ;
list.add (t);
}
} catch (SecurityException e) {
/ / TODO Auto-generated catch block
e.printStackTrace ();
} catch (IllegalArgumentException e) {
/ / TODO Auto-generated catch block
e.printStackTrace ();
} catch (JSONException e) {
/ / TODO Auto-generated catch block
e.printStackTrace ();
}
return list;
}
}
------ For reference only ---------------------------------- -----
------ For reference only ---------------------------------------
jsonArray.length () this line in question to jsonArray.size ()
------ For reference only ------------ ---------------------------
is org.json bag?
paste code for your reference
package cn.qtone.mobile.utils;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
------ For reference only ---------------------------------- -----
If this is how to do [{'id': '1 ',' uname ':' Tom ',' hobbies ': [{' name ':' Running '}, {' name ':' swim '}]}, {' id ': '2', 'uname': ' Joe Smith ', 'hobbies': [{'name': ' sleep '}, {'name': ' chat '} ] } ]
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