JAX-RS @ queryparam and @ defaultvalue

Let's take a look at @ queryparam
First look at the example:
 

Java code

2. PATH ("/users ")
3. Public class userservice {
5. @ Get
6. @ Path ("/query ")
7. Public Response getusers (
8. @ Queryparam ("from") int from,
9. @ Queryparam ("to") int,
10. @ Queryparam ("orderby") List <string> orderby ){
12. Return response
13. . Status (200)
14. . Entity ("getusers is called, from:" + from + ", to:" +
15. + ", Orderby" + orderby. tostring (). Build ();
17. }
19. }

Path("/users")public class UserService { @GET@Path("/query")public Response getUsers(@QueryParam("from") int from,@QueryParam("to") int to,@QueryParam("orderBy") List<String> orderBy) { return Response   .status(200)   .entity("getUsers is called, from : " + from + ", to : " + to+ ", orderBy" + orderBy.toString()).build(); } }

URL input: users/query? From = 100 & to = 200 & orderby = age & orderby = Name
In this case, the output is:
Getusers is called, from: 100, to: 200, orderby [age, name]
Note that, unlike @ pathparam, @ queryparam
The specified parameter in the URL is in the form of a key-value pair, and in the program
@ Queryparam ("from") int from reads the from Value in the URL,
In @ pathparem, only the parameter value is displayed in the URL, and no key-value pair is displayed, for example:
"/Users/2011/06/30"

Then:
 

Java code

1. @ Get
2. @ Path ("{year}/{month}/{day }")
3. Public Response getuserhistory (
4. @ Pathparam ("year") int year,
5. @ Pathparam ("month") int month,
6. @ Pathparam ("day") int day ){
8. String date = year + "/" + month + "/" + Day;
10. Return response. Status (200)
11. . Entity ("getuserhistory is called, year/month/day:" + date)
12. . Build ();
14. }

@GET@Path("{year}/{month}/{day}")public Response getUserHistory(@PathParam("year") int year,@PathParam("month") int month, @PathParam("day") int day) {    String date = year + "/" + month + "/" + day;    return Response.status(200).entity("getUserHistory is called, year/month/day : " + date).build(); }

Output:
Getuserhistory is called, year/month/day: 2011/6/30

2. Get it in a dynamic way:

Java code

1. @ Path ("/users ")
2. Public class userservice {
4. @ Get
5. @ Path ("/query ")
6. Public Response getusers (@ context uriinfo info ){
8. String from = info. getqueryparameters (). getfirst ("from ");
9. String to = info. getqueryparameters (). getfirst ("");
10. List <string> orderby = info. getqueryparameters (). Get ("orderby ");
12. Return response
13. . Status (200)
14. . Entity ("getusers is called, from:" + from + ", to:" +
15. + ", Orderby" + orderby. tostring (). Build ();
17. }

@Path("/users")public class UserService { @GET@Path("/query")public Response getUsers(@Context UriInfo info) { String from = info.getQueryParameters().getFirst("from");String to = info.getQueryParameters().getFirst("to");List<String> orderBy = info.getQueryParameters().get("orderBy"); return Response   .status(200)   .entity("getUsers is called, from : " + from + ", to : " + to+ ", orderBy" + orderBy.toString()).build(); } 

URL; users/query? From = 100 & to = 200 & orderby = age & orderby = Name
Output:
Getusers is called, from: 100, to: 200, orderby [age, name]
Note that the two parameters after orderby are read as list.

3 @ defaultvalue, default value

Example:
 

Java code

1. @ Path ("/users ")
2. Public class userservice {
4. @ Get
5. @ Path ("/query ")
6. Public Response getusers (
7. @ Defaultvalue ("1000") @ queryparam ("from") int from,
   
8. @ Defaultvalue ("999") @ queryparam ("to") int,
   
9. @ Defaultvalue ("name") @ queryparam ("orderby") List <string> orderby ){
   
11. Return response
12. . Status (200)
13. . Entity ("getusers is called, from:" + from + ", to:" +
14. + ", Orderby" + orderby. tostring (). Build ();
16. }

@Path("/users")public class UserService { @GET@Path("/query")public Response getUsers(@DefaultValue("1000") @QueryParam("from") int from,@DefaultValue("999")@QueryParam("to") int to,@DefaultValue("name") @QueryParam("orderBy") List<String> orderBy) { return Response   .status(200)   .entity("getUsers is called, from : " + from + ", to : " + to+ ", orderBy" + orderBy.toString()).build(); }

URL: users/Query
Output: getusers is called, from: 1000, to: 999, orderby [name]

Good understanding.