feat: Implemented StaffService with CRUD operation

src/main/java/com/wsmsdemo/service/StaffService.java

@@ -0,0 +1,58 @@
+package com.wsmsdemo.service;
+
+import com.wsmsdemo.model.Staff;
+import com.wsmsdemo.repository.StaffRepository;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+import java.util.List;
+import java.util.Optional;
+
+@Service
+public class StaffService {
+
+    @Autowired
+    private StaffRepository staffRepository;
+
+    public List<Staff> findAll() {
+        return staffRepository.findAll();
+    }
+
+    public Staff create(Staff staff) {
+        return staffRepository.save(staff);
+    }
+
+    public Staff update(Long id, Staff staff) {
+        Optional<Staff> existingStaff = staffRepository.findById(id);
+        if (existingStaff.isPresent()) {
+            Staff updatedStaff = existingStaff.get();
+            updatedStaff.setStaffName(staff.getStaffName());
+            updatedStaff.setCheckCode(staff.getCheckCode());
+            updatedStaff.setIsDelete(staff.getIsDelete());
+            updatedStaff.setIsLock(staff.getIsLock());
+            updatedStaff.setErrorCheckCodeCounter(staff.getErrorCheckCodeCounter());
+            return staffRepository.save(updatedStaff);
+        } else {
+            throw new RuntimeException("Staff not found with id " + id);
+        }
+    }
+
+    public void delete(Long id) {
+        staffRepository.deleteById(id);
+    }
+
+    public Staff partialUpdate(Long id, Staff staff) {
+        Optional<Staff> existingStaff = staffRepository.findById(id);
+        if (existingStaff.isPresent()) {
+            Staff updatedStaff = existingStaff.get();
+            if (staff.getStaffName() != null) updatedStaff.setStaffName(staff.getStaffName());
+            if (staff.getCheckCode() != null) updatedStaff.setCheckCode(staff.getCheckCode());
+            if (staff.getIsDelete() != null) updatedStaff.setIsDelete(staff.getIsDelete());
+            if (staff.getIsLock() != null) updatedStaff.setIsLock(staff.getIsLock());
+            if (staff.getErrorCheckCodeCounter() != null) updatedStaff.setErrorCheckCodeCounter(staff.getErrorCheckCodeCounter());
+            return staffRepository.save(updatedStaff);
+        } else {
+            throw new RuntimeException("Staff not found with id " + id);
+        }
+    }
+}