Use JSON-lib to convert a Java object to a JSON string
After learning to use Ajax in J2EE, sometimes the client data returned from the server is an object. It is easy to make errors when you manually piece together the JSON string. Google knows the JSON-lib class library, it is convenient to support conversion from Java objects to JSON strings.
See the JSON-lib introduction of source-Forge.
Jakarta commons-lang 2.4
Jakarta commons-beanutils 1.7.0
Jakarta commons-collections 3.2
Jakarta commons-logging 1.1.1
Ezmorph 1.0.6
The support for these jar packages has been downloaded and tried, which is quite useful.CodeThere are three cases: 1 object 2 List 3 object and list object)
1 object:
package COM. JSON. action. main; </P> <p> Import Java. text. simpledateformat; </P> <p> Import net. SF. JSON. jsonobject; </P> <p> Import COM. JSON. model. usermodel; </P> <p> public class userobjectjsonmain {</P> <p> Public static void main (string [] ARGs) {</P> <p> simpledateformat SDF = new simpledateformat ("Yyyy-mm-dd hh: mm: SS"); </P> <p> usermodel UA = new usermodel (); <br/> UA. setid (11); <br/> UA. settitle ("JSON transmission"); <br/> UA. setcontent ("Convert Java object to JSON file format! "); <Br/> UA. setcurrent (SDF. format (New Java. util. date (); <br/> jsonobject = jsonobject. fromobject (UA); <br/> system. out. println ("Java object to JSON:" + jsonobject ); <br/>}</P> <p >}< br/>
2 list
Package COM. JSON. action. main; </P> <p> Import Java. text. simpledateformat; <br/> Import Java. util. arraylist; <br/> Import Java. util. list; <br/> Import net. SF. JSON. jsonarray; </P> <p> Import COM. JSON. model. usermodel; </P> <p> public class userlistjsonmain {</P> <p> Public static void main (string [] ARGs) {<br/> simpledateformat SDF = new simpledateformat ("yyyy-mm-dd hh: mm: SS"); </P> <p> List <usermodel> List = new ARRA Ylist <usermodel> (); <br/> for (INT I = 1; I <10; I ++) {<br/> usermodel user = new usermodel (); <br/> User. setid (I); <br/> User. settitle ("JSON transmission" + I); <br/> User. setcontent ("Convert Java object to JSON file format! "+ I); <br/> User. setcurrent (SDF. format (New Java. util. date (); <br/> list. add (User); <br/>}</P> <p> jsonarray = jsonarray. fromobject (list); <br/> system. out. println (jsonarray); </P> <p >}< br/>
3 object and list
Package COM. JSON. action. main; </P> <p> Import Java. text. simpledateformat; <br/> Import Java. util. arraylist; <br/> Import Java. util. hashmap; <br/> Import Java. util. list; <br/> Import Java. util. map; </P> <p> Import net. SF. JSON. jsonobject; </P> <p> Import COM. JSON. model. usermodel; </P> <p> public class userlistobjectjsonmain {</P> <p> Public static void main (string [] ARGs) {<br/> simpledateformat SDF = new simpledateform At ("yyyy-mm-dd hh: mm: SS"); </P> <p> usermodel UA = new usermodel (); <br/> UA. setid (11); <br/> UA. settitle ("JSON transmission"); <br/> UA. setcontent ("Convert Java object to JSON file format! "); <Br/> UA. setcurrent (SDF. format (New Java. util. date (); </P> <p> List <usermodel> List = new arraylist <usermodel> (); <br/> for (INT I = 1; I <10; I ++) {<br/> usermodel user = new usermodel (); <br/> User. setid (I); <br/> User. settitle ("JSON transmission" + I); <br/> User. setcontent ("Convert Java object to JSON file format! "+ I); <br/> User. setcurrent (SDF. format (New Java. util. date (); <br/> list. add (User); <br/>}</P> <p> // when both objects and arrays exist <br/> Map <string, object> map = new hashmap <string, Object> (); <br/> map. put ("UA", UA); <br/> map. put ("lis", list); </P> <p> jsonobject jsonobjectfrommap = jsonobject. fromobject (MAP); <br/> system. out. println (jsonobjectfrommap); </P> <p >}< br/>
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