Java uses reflection mapping JSON object as JavaBean

About converting Jsonobject to JavaBean, in fact, there is a Tobean () method in Jsonobject to deal with, also can be based on a given jsonconfig to deal with the corresponding requirements, such as filtering the specified properties

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2. //Returns TRUE to filter out the attribute   
4. Jsonconfig.setjsonpropertyfilter (new propertyfilter () {
6. @Override   
8. Public boolean apply (object o, String N, Object v) {
10. return          false;
12. }
14. });

Returns true to filter out the attribute Jsonconfig.setjsonpropertyfilter (new PropertyFilter () {    @Override public    Boolean apply ( Object o, String N, Object v) {        return false;           }});  

set default values for some properties
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2. //When serializing to JSON, set the integer object to null   
4. Jsonconfig.registerdefaultvalueprocessor (Integer. Class,
6. New defaultvalueprocessor () {
8. @SuppressWarnings ("unchecked")
10. @Override   
12. Public Object getdefaultvalue (Class type) {
14. return   "";
16. }
18. });

When serializing to JSON, set the Integer object to Nulljsonconfig.registerdefaultvalueprocessor (Integer.class,    new Defaultvalueprocessor () {        @SuppressWarnings ("unchecked")        @Override public        Object Getdefaultvalue ( Class type) {            return "";        }});

There are other useful methods that are not introduced here ..., but in practice, the properties in the JavaBean that are converted to JSON objects may also be a JSON object or a JSON array, but in the property is a string type. This causes the type conversion to fail when the JSON object is converted to JavaBean. The method for Jsonconfig was looked up, and no method was found to process Jsonobject or Jsonarray as string in the Json-->bean process, so only reflection can be used to complete the mapping of special objects. Here's what to note:
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1. when Jsonobject encounters a JSON string that is NULL , it will return to Jsonnull.

When Jsonobject encounters a JSON string that is NULL, it returns JSONNULL

Therefore, you need to pay special attention when judging to be empty. The code is as follows [HTML]View PlainCopyPrint?

2. public static examblobs Parsejsontoexam (Jsonobject obj) {
4. Examblobs exam = new examblobs ();
6. try {
8. List<Field> fieldlist = new ArrayList   <Field>();
10. FieldList
12. . AddAll (Arrays.aslist (Exam.getclass (). Getdeclaredfields ()));
14. for (Field field:fieldlist) {
16. String name = field. GetName ();
18. Object value = obj. Get (name);
20. if (value! = NULL &&!) ( Value instanceof Jsonnull)) {
22. Makes it possible to copy a private property
24. Field.setaccessible (TRUE);
26. if (Name.equalsignorecase ("Option")) {
28. Jsonarray jarr = (jsonarray) value;
30. Field.set (Exam, jarr.tostring ());
32. } else {
34. String type = field. GetType (). toString ();
36. if (Type.indexof ("Integer") >= 0) {
38. Field.set (Exam, (Integer) value);
40. } else if (Type.indexof ("String") >= 0) {
42. Field.set (Exam, (String) value);
44. } else if (Type.indexof ("Date") >= 0) {
46. Jsonobject dataobj = (jsonobject) value;
48. Field.set (Exam,
50. Jsonobject.tobean (Dataobj, Date.class));
52. }
54. }
56. }
58. }
60. } catch (SecurityException e) {
62. E.printstacktrace ();
64. } catch (IllegalArgumentException e) {
66. E.printstacktrace ();
68. } catch (Illegalaccessexception e) {
70. E.printstacktrace ();
72. }
74. return exam;
76. }

public static examblobs Parsejsontoexam (Jsonobject obj) {examblobs exam = new Examblobs ();        try {list<field> fieldlist = new arraylist<field> ();        FieldList. AddAll (Arrays.aslist (Exam.getclass (). Getdeclaredfields ()));            for (Field field:fieldlist) {String name = Field.getname ();            Object value = obj.get (name); if (value! = NULL &&!) (                Value instanceof Jsonnull) {//makes it possible to copy field.setaccessible (true) to a private property;                    if (Name.equalsignorecase ("Option")) {Jsonarray Jarr = (jsonarray) value;                Field.set (Exam, jarr.tostring ());                    } else {String type = Field.gettype (). toString ();                    if (Type.indexof ("integer") >= 0) {field.set (exam, (integer) value); } else if (Type.indexof ("String") >= 0) {field.set (Exam, (striNG) value);                        } else if (Type.indexof ("Date") >= 0) {jsonobject dataobj = (jsonobject) value;                    Field.set (Exam, Jsonobject.tobean (dataobj, Date.class));    }}}}} catch (SecurityException e) {e.printstacktrace ();    } catch (IllegalArgumentException e) {e.printstacktrace ();    } catch (Illegalaccessexception e) {e.printstacktrace (); } return exam;}

Java uses reflection mapping JSON object as JavaBean