Changes order parameter to id

apache-cxf/cxf-jaxrs-implementation/src/main/java/com/baeldung/cxf/jaxrs/implementation/Baeldung.java

@@ -37,27 +37,36 @@ public class Baeldung {
     }
 
     @GET
-    @Path("courses/{courseOrder}")
-    public Course getCourse(@PathParam("courseOrder") int courseOrder) {
-        return courses.get(courseOrder);
+    @Path("courses/{courseId}")
+    public Course getCourse(@PathParam("courseId") int courseId) {
+        return findById(courseId);
     }
 
     @PUT
-    @Path("courses/{courseOrder}")
-    public Response updateCourse(@PathParam("courseOrder") int courseOrder, Course course) {
-        Course existingCourse = courses.get(courseOrder);        
+    @Path("courses/{courseId}")
+    public Response updateCourse(@PathParam("courseId") int courseId, Course course) {
+        Course existingCourse = findById(courseId);
         if (existingCourse == null) {
             return Response.status(Response.Status.NOT_FOUND).build();
         }
         if (existingCourse.equals(course)) {
-            return Response.notModified().build();    
+            return Response.notModified().build();
         }
-        courses.put(courseOrder, course);
+        courses.put(courseId, course);
         return Response.ok().build();
     }
 
-    @Path("courses/{courseOrder}/students")
-    public Course pathToStudent(@PathParam("courseOrder") int courseOrder) {
-        return courses.get(courseOrder);
+    @Path("courses/{courseId}/students")
+    public Course pathToStudent(@PathParam("courseId") int courseId) {
+        return findById(courseId);
+    }
+
+    private Course findById(int id) {
+        for (Map.Entry<Integer, Course> course : courses.entrySet()) {
+            if (course.getKey() == id) {
+                return course.getValue();
+            }
+        }
+        return null;
     }
 }

apache-cxf/cxf-jaxrs-implementation/src/main/java/com/baeldung/cxf/jaxrs/implementation/Course.java

@@ -11,7 +11,7 @@ import java.util.List;
 public class Course {
     private int id;
     private String name;
-    private List<Student> students;
+    private List<Student> students = new ArrayList<>();
 
     public int getId() {
         return id;
@@ -38,16 +38,13 @@ public class Course {
     }
 
     @GET
-    @Path("{studentOrder}")
-    public Student getStudent(@PathParam("studentOrder") int studentOrder) {
-        return students.get(studentOrder);
+    @Path("{studentId}")
+    public Student getStudent(@PathParam("studentId") int studentId) {
+        return findById(studentId);
     }
 
     @POST
     public Response createStudent(Student student) {
-        if (students == null) {
-            students = new ArrayList<>();
-        }
         if (students.contains(student)) {
             return Response.status(Response.Status.CONFLICT).build();
         }
@@ -56,14 +53,24 @@ public class Course {
     }
 
     @DELETE
-    @Path("{studentOrder}")
-    public Response deleteStudent(@PathParam("studentOrder") int studentOrder) {
-        if (students == null || studentOrder >= students.size()) {
+    @Path("{studentId}")
+    public Response deleteStudent(@PathParam("studentId") int studentId) {
+        Student student = findById(studentId);
+        if (student == null) {
             return Response.status(Response.Status.NOT_FOUND).build();
         }
-        students.remove(studentOrder);
+        students.remove(student);
         return Response.ok().build();
     }
+    
+    private Student findById(int id) {
+        for (Student student : students) {
+            if (student.getId() == id) {
+                return student;
+            }
+        }
+        return null;
+    }
 
     @Override
     public int hashCode() {

apache-cxf/cxf-jaxrs-implementation/src/main/resources/conflict_student.xml

@@ -1,4 +1,4 @@
 <Student>
-    <id>1</id>
-    <name>Student A</name>
+    <id>2</id>
+    <name>Student B</name>
 </Student>

apache-cxf/cxf-jaxrs-implementation/src/test/java/com/baeldung/cxf/jaxrs/implementation/ServiceTest.java

@@ -91,21 +91,21 @@ public class ServiceTest {
         HttpResponse response = client.execute(httpPost);
         assertEquals(200, response.getStatusLine().getStatusCode());
         
-        Student student = getStudent(2, 0);
+        Student student = getStudent(2, 3);
         assertEquals(3, student.getId());
         assertEquals("Student C", student.getName());
     }
     
     @Test
     public void whenDeleteInvalidStudent_thenReceiveNotFoundResponse() throws IOException {
-        HttpDelete httpDelete = new HttpDelete(BASE_URL + "1/students/2");
+        HttpDelete httpDelete = new HttpDelete(BASE_URL + "1/students/3");
         HttpResponse response = client.execute(httpDelete);
         assertEquals(404, response.getStatusLine().getStatusCode());
     }   
     
     @Test
     public void whenDeleteValidStudent_thenReceiveOKResponse() throws IOException {
-        HttpDelete httpDelete = new HttpDelete(BASE_URL + "1/students/0");
+        HttpDelete httpDelete = new HttpDelete(BASE_URL + "1/students/1");
         HttpResponse response = client.execute(httpDelete);
         assertEquals(200, response.getStatusLine().getStatusCode());