Implements findAll and findById

src/main/java/com/StudentServices/MarksService/controller/StudentMarksController.java

 package com.StudentServices.MarksService.controller;
 
+import com.StudentServices.MarksService.model.StudentMarks;
 import com.StudentServices.MarksService.service.StudentService;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.*;
 
@@ -16,11 +18,23 @@ public class StudentMarksController {
     @Autowired StudentService studentService;
 
     // (GET) findall studentmarks
-
+    @GetMapping
+    ResponseEntity<List<StudentMarks>> findAllStudentMarks(){
+        return ResponseEntity.ok(studentService.findAllStudents());
+    }
     // (POST) create studentmark
 
     // (GET) find studentmark by id
-
+    @GetMapping
+    ResponseEntity<StudentMarks> findStudentMarksById(String id){
+        StudentMarks sm = studentService.getStudentById(id);
+        if (sm == null){
+            return new ResponseEntity<>(HttpStatus.NOT_FOUND);
+        }
+        else {
+            return ResponseEntity.ok(sm);
+        }
+    }
     // (PUT) update studentmark by id
 
     // (DELETE) delete studentmark by id

src/main/java/com/StudentServices/MarksService/service/StudentService.java

@@ -7,6 +7,7 @@ import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
 
 import java.util.List;
+import java.util.Optional;
 
 @Service
 public class StudentService {
@@ -26,7 +27,8 @@ public class StudentService {
     }
 
     public StudentMarks getStudentById(String ID) {
-        return null;
+        Optional<StudentMarks> sm = studentRepository.findById(ID);
+        return sm.orElse(null);
     }
 
     public void updateStudent(StudentMarks studentMarks) {