diff --git a/src/main/java/org/ntlab/amaryllis/server/resources/VoicememosRest.java b/src/main/java/org/ntlab/amaryllis/server/resources/VoicememosRest.java
index a775751..e118f65 100644
--- a/src/main/java/org/ntlab/amaryllis/server/resources/VoicememosRest.java
+++ b/src/main/java/org/ntlab/amaryllis/server/resources/VoicememosRest.java
@@ -7,9 +7,12 @@
 import org.springframework.stereotype.Component;
 
 import javax.ws.rs.*;
+import javax.ws.rs.core.Application;
 import javax.ws.rs.core.MediaType;
 import java.awt.*;
 import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.Map;
 import java.util.UUID;
 
 @Component
@@ -20,50 +23,73 @@
 
     @GET
     @Produces(MediaType.APPLICATION_JSON)
-    public String getVoicememos(@QueryParam("latmax") double latmax, @QueryParam("latmin") double latmin, @QueryParam("longmax") double longmax, @QueryParam("longmin") double longmin) {
-        String vidlist = "";
+    public Map<String,ArrayList> getVoicememos(@QueryParam("latmax") Double latmax, @QueryParam("latmin") Double latmin, @QueryParam("longmax") Double longmax, @QueryParam("longmin") Double longmin) {
+        if (latmax == null || latmin == null || longmax == null || longmin == null) {
+            throw new WebApplicationException(400);
+        }
+        Map<String,ArrayList> gettingVid = new HashMap<String,ArrayList>();
+        ArrayList<String> vidlist = new ArrayList<>();
         for (Voicememo v :
                 voicememos.getVoicememos()) {
             String vid = v.getVid();
             double latitude = v.getLatitude();
             double longitude = v.getLongitude();
-            if (latmax > latitude && latitude > latmin && longmax > longitude && longmin > longitude) {
-                vidlist = vidlist + vid;
+            if (latmax > latitude && latitude > latmin && longmax > longitude &&  longitude > longmin ) {
+                vidlist.add(vid);
             }
         }
-        return vidlist;
+        gettingVid.put("voicememos",vidlist);
+        return gettingVid;
     }
 
     @POST
     @Produces(MediaType.APPLICATION_JSON)
-    public String addVoicememos(@FormParam("token") String client_token, @FormParam("uid") String uid, @FormParam("time") int time, @FormParam("data") String data, @FormParam("latitude") double latitude, @FormParam("longitude") double longitude, @FormParam("title") String title, @FormParam("summary") String summary) {
+    public String addVoicememos(@FormParam("token") String client_token, @FormParam("uid") String uid, @FormParam("time") Integer time, @FormParam("data") String data, @FormParam("latitude") Double latitude, @FormParam("longitude") Double longitude, @FormParam("title") String title, @FormParam("summary") String summary) {
+        if (client_token == null || uid == null || time == null || data == null || latitude == null || longitude == null || title == null) {
+            throw new WebApplicationException(400);
+        }
         Account account = accounts.getAccount(uid);
         String server_token = account.getToken();
-        if (client_token.equals(server_token))  {
+        if (client_token.equals(server_token)) {
             Voicememo v = voicememos.createVoicememo(uid, time, data, latitude, longitude, title, summary);
+            if (v == null) {
+                throw new WebApplicationException(400);
+            }
             String vid = v.getVid();
             return vid;
         }
-        return null;
+        Voicememo v = voicememos.createVoicememo(uid, time, data, latitude, longitude, title, summary);
+        if (v == null) {
+            throw new WebApplicationException(400);
+        }
+
+        throw new WebApplicationException(400);
     }
 
     @Path("/{vid}")
     @GET
     @Produces(MediaType.APPLICATION_JSON)
-    public Voicememo getVoicememo(@PathParam("vid") String vid, @QueryParam("token") String client_token, @QueryParam("uid") String uid, @QueryParam("time") int time) {
+    public Voicememo getVoicememo(@PathParam("vid") String vid, @QueryParam("token") String client_token, @QueryParam("uid") String uid, @QueryParam("time") Integer time) {
+        if (vid == null || client_token == null || uid == null) {
+            throw new WebApplicationException(400);
+        }
         Account account = accounts.getAccount(uid);
         String server_token = account.getToken();
         if (client_token.equals(server_token)) {
             Voicememo voicememo = voicememos.getVoicememo(vid);
             return voicememo;
         }
-        return null;
+
+        throw new WebApplicationException(400);
     }
 
     @Path("/{vid}")
     @PUT
     @Produces(MediaType.APPLICATION_JSON)
     public void correctVoicememo(@PathParam("vid") String vid, @FormParam("token") String client_token, @FormParam("uid") String uid, @FormParam("title") String title, @FormParam("summary") String summary) {
+        if (vid == null || client_token == null || uid == null || title == null) {
+            throw new WebApplicationException(400);
+        }
         Account account = accounts.getAccount(uid);
         String server_token = account.getToken();
         if (client_token.equals(server_token)) {
@@ -72,20 +98,23 @@
             v.setTitle(title);
             return;
         }
-
+        throw new WebApplicationException(400);
     }
 
     @Path("/{vid}")
     @DELETE
     @Produces(MediaType.APPLICATION_JSON)
-    public void deleteVoicememo(@PathParam("vid") String vid, @FormParam("token") String client_token, @FormParam("uid") String uid){
+    public void deleteVoicememo(@PathParam("vid") String vid, @FormParam("token") String client_token, @FormParam("uid") String uid) {
+        if (vid == null || client_token == null || uid == null) {
+            throw new WebApplicationException(400);
+        }
         Account account = accounts.getAccount(uid);
         String server_token = account.getToken();
         if (client_token.equals(server_token)) {
             voicememos.removeVoicememo(vid);
             return;
         }
-
+        throw new WebApplicationException(400);
     }
 
 }