diff --git a/src/main/java/org/ntlab/citrusserver/repositories/AccountManager.java b/src/main/java/org/ntlab/citrusserver/repositories/AccountManager.java
index 602395f..bd65aae 100644
--- a/src/main/java/org/ntlab/citrusserver/repositories/AccountManager.java
+++ b/src/main/java/org/ntlab/citrusserver/repositories/AccountManager.java
@@ -19,16 +19,14 @@
 
     // account_idとpasswordを設定し新しいアカウントを作成する(POST)
     public String createAccount(String accountId, String password) {
+        UUID str = UUID.randomUUID();
+        String token = str.toString();
+        Account account = new Account(accountId, password);
         if(!accounts.containsKey(accountId)) {
-            UUID str = UUID.randomUUID();
-            String token = str.toString();
-            Account account = new Account(accountId, password);
             accounts.put(accountId, account);
             accountToken.put(accountId, token); //accountIDとtokenをHashMapに入れる
-            return token;
-        } else {
-            return null;
         }
+        return token;
     }
 
     //accountIdとtokenを比較してtrueかfalseを返す
diff --git a/src/main/java/org/ntlab/citrusserver/repositories/FavoriteManager.java b/src/main/java/org/ntlab/citrusserver/repositories/FavoriteManager.java
new file mode 100644
index 0000000..b3b0e12
--- /dev/null
+++ b/src/main/java/org/ntlab/citrusserver/repositories/FavoriteManager.java
@@ -0,0 +1,79 @@
+package org.ntlab.citrusserver.repositories;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Repository;
+
+import java.util.HashMap;
+import java.util.HashSet;
+
+
+import java.util.HashMap;
+import java.util.HashSet;
+
+@Repository
+public class FavoriteManager {
+    private final AccountManager accountManager;
+
+    @Autowired
+    public FavoriteManager(AccountManager accountManager) {
+        this.accountManager = accountManager;
+    }
+
+    private final HashMap<String, //accountid
+            HashMap<Integer, //bookid
+                    HashSet<String>>> //otheraccounts
+            favoritedMap = new HashMap<>();
+
+
+    //book_idをいいねしたaccount_idをリストとして返す
+    public HashSet<String> getFavorited(String accountId, int bookId) {
+        if(accountManager.getAccount(accountId) == null) return null; //アカウントが存在しない
+
+        return favoritedMap.get(accountId).get(bookId);
+    }
+
+    //other_account_idの人がaccount_idのbook_idにいいねをした時
+    public void putFavorited(String accountId, int bookId, String otherAccountId) {
+        favoritedMap.get(accountId).get(bookId).add(otherAccountId);
+    }
+
+    //イイねしたaccount_idをイイねした人リストから削除
+    public void removeFavorited(String accountId, int bookId, String otherAccountId) {
+        favoritedMap.get(accountId).get(bookId).remove(otherAccountId);
+    }
+
+
+
+
+    HashMap<String, HashMap<String , HashSet<Integer>>> favoritesMap = new HashMap();
+
+
+    //いいねした本の一覧を返す
+    public HashMap<String, HashSet<Integer>> getFavorites(String accountId) {
+        if(accountManager.getAccount(accountId) == null) return null;
+        return favoritesMap.get(accountId);
+    }
+
+    //取得したotherAccountIdのいいねした本を返す
+    public HashSet<Integer> getFavoritesByID(String accountId, String otherAccountId) {
+        if(accountManager.getAccount(accountId) == null) return null;
+        if(!favoritesMap.get(accountId).containsKey(otherAccountId)) return null;
+        return favoritesMap.get(accountId).get(otherAccountId);
+    }
+
+    //いいねした本を追加する
+    public void putFavorites(String accountId, String otherAccountId, Integer bookId) {
+        if(!favoritesMap.containsKey(accountId)){
+            favoritesMap.put(accountId, new HashMap<>());
+        }
+        if(!favoritesMap.get(accountId).containsKey(otherAccountId)){
+            favoritesMap.get(accountId).put(otherAccountId, new HashSet<>());
+        }
+        favoritesMap.get(accountId).get(otherAccountId).add(bookId);
+
+    }
+    //いいねした本を消去する
+    public void removeFavorites(String accountId, String otherAccountId, Integer bookId) {
+        favoritesMap.get(accountId).get(otherAccountId).remove(bookId);
+    }
+
+}
diff --git a/src/main/java/org/ntlab/citrusserver/resources/AccountsRest.java b/src/main/java/org/ntlab/citrusserver/resources/AccountsRest.java
index 1a430e6..ed7b686 100644
--- a/src/main/java/org/ntlab/citrusserver/resources/AccountsRest.java
+++ b/src/main/java/org/ntlab/citrusserver/resources/AccountsRest.java
@@ -47,10 +47,6 @@
     public String signup(@FormParam("account_id") String accountId, @FormParam("password") String password) {
         String token;
         token = accountManager.createAccount(accountId, password);
-        if (token == null){
-            var response = Response.status(Response.Status.CONFLICT).entity("id '" + accountId +  "' は既に存在します");//404
-            throw new WebApplicationException(response.build());
-        }
         return token;
     }
 
diff --git a/src/main/java/org/ntlab/citrusserver/resources/BooksRest.java b/src/main/java/org/ntlab/citrusserver/resources/BooksRest.java
index 6e8982c..3398b0b 100644
--- a/src/main/java/org/ntlab/citrusserver/resources/BooksRest.java
+++ b/src/main/java/org/ntlab/citrusserver/resources/BooksRest.java
@@ -39,9 +39,19 @@
     @Produces(MediaType.APPLICATION_JSON)
     public  HashMap<Integer, Book> getBooks(@PathParam("account_id") String account_id, @QueryParam("token") String token){
 
-        accountCheck(account_id);
-        tokenCheck(account_id, token);
-        return bookManager.getBooks(account_id);
+        if(accountManager.getAccount(account_id) == null){
+            var response = Response.status(Response.Status.NOT_FOUND).entity("アカウントが見つかりません");
+            throw new WebApplicationException(response.build());
+        }
+        else{
+            if(!accountManager.checkToken(account_id, token)) {
+                var response = Response.status(Response.Status.FORBIDDEN).entity("認証失敗");
+                throw new WebApplicationException(response.build());
+            }
+            else{
+                return bookManager.getBooks(account_id);
+            }
+        }
     }
 
     @Path("/{account_id}/books")
@@ -50,9 +60,19 @@
     @Consumes(MediaType.APPLICATION_FORM_URLENCODED)  // postmanのbodyに入力する値がある時
     public Book createBook(@PathParam("account_id") String account_id, @FormParam("title") String title, @FormParam("color") String color, @FormParam("publicity") Boolean publicity, @FormParam("token") String token) {
 
-        accountCheck(account_id);
-        tokenCheck(account_id, token);
-        return bookManager.createBook(account_id, title, color, publicity);
+        if (accountManager.getAccount(account_id) == null){
+            var response = Response.status(Response.Status.NOT_FOUND).entity("アカウントが見つかりません");
+            throw new WebApplicationException(response.build());
+        }
+        else{
+            if(!accountManager.checkToken(account_id, token)) {
+                var response = Response.status(Response.Status.FORBIDDEN).entity("認証失敗");
+                throw new WebApplicationException(response.build());
+            }
+            else {
+                return bookManager.createBook(account_id, title, color, publicity);
+            }
+        }
     }
 
 
@@ -63,9 +83,19 @@
     @Produces(MediaType.APPLICATION_JSON)
     public Book getBook(@PathParam("account_id") String account_id, @PathParam("book_id") Integer book_id, @QueryParam("token") String token){
 
-        accountCheck(account_id);
-        tokenCheck(account_id, token);
-        return bookManager.getBook(account_id, book_id);
+        if (accountManager.getAccount(account_id) == null){
+            var response = Response.status(Response.Status.NOT_FOUND).entity("アカウントが見つかりません");
+            throw new WebApplicationException(response.build());
+        }
+        else{
+            if(!accountManager.checkToken(account_id, token)) {
+                var response = Response.status(Response.Status.FORBIDDEN).entity("認証失敗");
+                throw new WebApplicationException(response.build());
+            }
+            else{
+                return bookManager.getBook(account_id, book_id);
+            }
+        }
     }
   /// 本の削除
     @Path("/{account_id}/books/{book_id}")
@@ -74,11 +104,21 @@
     @Consumes(MediaType.APPLICATION_FORM_URLENCODED)
     public String deleteBook(@PathParam("account_id") String account_id, @PathParam("book_id") Integer book_id, @QueryParam("token") String token){
 
-        accountCheck(account_id);
-        tokenCheck(account_id, token);
-        todoManager.deleteAllTodosByBookId(account_id, book_id);//削除時、Todoも消す
-        bookManager.deleteBook(account_id, book_id);
-        return "success";
+        if(accountManager.getAccount(account_id) == null){
+            var response = Response.status(Response.Status.NOT_FOUND).entity("アカウントが見つかりません");
+            throw new WebApplicationException(response.build());
+        }
+        else{
+            if(!accountManager.checkToken(account_id, token)) {
+                var response = Response.status(Response.Status.FORBIDDEN).entity("認証失敗");
+                throw new WebApplicationException(response.build());
+            }
+            else{
+                todoManager.deleteAllTodosByBookId(account_id, book_id);//削除時、Todoも消す
+                bookManager.deleteBook(account_id, book_id);
+                return "success";
+            }
+        }
     }
 
 /// /{account_id}/books/{book_id}/title
@@ -88,9 +128,19 @@
     @Produces(MediaType.TEXT_PLAIN)
     public String getTitle(@PathParam("account_id") String account_id, @PathParam("book_id") Integer book_id, @QueryParam("token") String token){
 
-        accountCheck(account_id);
-        tokenCheck(account_id, token);
-        return bookManager.getTitle(account_id, book_id);
+        if (accountManager.getAccount(account_id) == null) {
+            var response = Response.status(Response.Status.NOT_FOUND).entity("アカウントが見つかりません");
+            throw new WebApplicationException(response.build());
+        }
+        else{
+            if(!accountManager.checkToken(account_id, token)) {
+                var response = Response.status(Response.Status.FORBIDDEN).entity("認証失敗");
+                throw new WebApplicationException(response.build());
+            }
+            else{
+                return bookManager.getTitle(account_id, book_id);
+            }
+        }
     }
 
   /// 本のタイトル変更
@@ -100,10 +150,20 @@
     @Consumes(MediaType.APPLICATION_FORM_URLENCODED)
     public String putTitle(@PathParam("account_id") String account_id, @PathParam("book_id") Integer book_id, @FormParam("title") String title, @FormParam("token") String token){
 
-        accountCheck(account_id);
-        tokenCheck(account_id, token);
-        bookManager.putTitle(account_id, book_id, title);
-        return "success";
+        if(accountManager.getAccount(account_id) == null){
+            var response = Response.status(Response.Status.NOT_FOUND).entity("アカウントが見つかりません");
+            throw new WebApplicationException(response.build());
+        }
+        else{
+            if(!accountManager.checkToken(account_id, token)) {
+                var response = Response.status(Response.Status.FORBIDDEN).entity("認証失敗");
+                throw new WebApplicationException(response.build());
+            }
+            else{
+                bookManager.putTitle(account_id, book_id, title);
+                return "success";
+            }
+        }
     }
 
 /// /accounts/{account_id}/books/{book_id}/public
@@ -113,9 +173,19 @@
     @Produces(MediaType.TEXT_PLAIN)
     public Boolean getPublicity(@PathParam("account_id") String account_id, @PathParam("book_id") Integer book_id, @QueryParam("token") String token){
 
-        accountCheck(account_id);
-        tokenCheck(account_id, token);
-        return bookManager.getPublicity(account_id, book_id);
+        if (accountManager.getAccount(account_id) == null) {
+            var response = Response.status(Response.Status.NOT_FOUND).entity("アカウントが見つかりません");
+            throw new WebApplicationException(response.build());
+        }
+        else{
+            if(!accountManager.checkToken(account_id, token)) {
+                var response = Response.status(Response.Status.FORBIDDEN).entity("認証失敗");
+                throw new WebApplicationException(response.build());
+            }
+            else{
+                return bookManager.getPublicity(account_id, book_id);
+            }
+        }
     }
 
   /// 公開情報を変更する
@@ -125,10 +195,20 @@
     @Consumes(MediaType.APPLICATION_FORM_URLENCODED)
     public String putPublicity(@PathParam("account_id") String account_id, @PathParam("book_id") Integer book_id, @FormParam("publicity") Boolean publicity, @FormParam("token") String token){
 
-        accountCheck(account_id);
-        tokenCheck(account_id, token);
-        bookManager.putPublicity(account_id, book_id, publicity);
-        return "success";
+        if(accountManager.getAccount(account_id) == null){
+            var response = Response.status(Response.Status.NOT_FOUND).entity("アカウントが見つかりません");
+            throw new WebApplicationException(response.build());
+        }
+        else{
+            if(!accountManager.checkToken(account_id, token)) {
+                var response = Response.status(Response.Status.FORBIDDEN).entity("認証失敗");
+                throw new WebApplicationException(response.build());
+            }
+            else{
+                bookManager.putPublicity(account_id, book_id, publicity);
+                return "success";
+            }
+        }
     }
 
 /// /accounts/{account_id}/books/{book_id}/color
@@ -138,27 +218,24 @@
     @Consumes(MediaType.APPLICATION_FORM_URLENCODED)
     public String putColor(@PathParam("account_id") String account_id, @PathParam("book_id") Integer book_id, @FormParam("color") String color, @FormParam("token") String token){
 
-        accountCheck(account_id);
-        tokenCheck(account_id, token);
-        bookManager.putColor(account_id, book_id, color);
-        return "success";
+        if(accountManager.getAccount(account_id) == null){
+            var response = Response.status(Response.Status.NOT_FOUND).entity("アカウントが見つかりません");
+            throw new WebApplicationException(response.build());
+        }
+        else{
+            if(!accountManager.checkToken(account_id, token)) {
+                var response = Response.status(Response.Status.FORBIDDEN).entity("認証失敗");
+                throw new WebApplicationException(response.build());
+            }
+            else{
+                bookManager.putColor(account_id, book_id, color);
+                return "success";
+            }
+        }
     }
 
     ///---------------------------------------------------------------------
     ///private
     ///---------------------------------------------------------------------
 
-    private void accountCheck(String account_id){
-        if(accountManager.getAccount(account_id) == null){
-            var response = Response.status(Response.Status.NOT_FOUND).entity("アカウントが見つかりません");
-            throw new WebApplicationException(response.build());
-        }
-    }
-
-    private void tokenCheck(String account_id, String token){
-        if(!accountManager.checkToken(account_id, token)) {
-            var response = Response.status(Response.Status.FORBIDDEN).entity("認証失敗");
-            throw new WebApplicationException(response.build());
-        }
-    }
 }
\ No newline at end of file
diff --git a/src/main/java/org/ntlab/citrusserver/resources/PublicBooksRest.java b/src/main/java/org/ntlab/citrusserver/resources/PublicBooksRest.java
index 0ca017f..8f5aac4 100644
--- a/src/main/java/org/ntlab/citrusserver/resources/PublicBooksRest.java
+++ b/src/main/java/org/ntlab/citrusserver/resources/PublicBooksRest.java
@@ -27,30 +27,30 @@
     }
 
 
-    //検索条件を指定して本を検索(アカウントかタイトルか両方 ソート可能)
+    //検索条件を指定して本を検索(アカウントかタイトルか両方)
     @Path("/search")
     @GET
     @Produces(MediaType.APPLICATION_JSON)
     public ArrayList<Book> searchBooksByTitleAndAccount(@QueryParam("search_title") String search_title, @QueryParam("search_account_id") String search_account_id,
                                                         @QueryParam("sort_by") Integer sort_by) {
-        if(sort_by == null) { //ソートしない場合
-            if (search_title != null && search_account_id != null) { //タイトルとアカウントIDでの検索
+        if(sort_by == null) {
+            if (search_title != null && search_account_id != null) {
                 return publicBookManager.searchBooksByTitleAndAccount(search_title, search_account_id);
-            } else if (search_title != null) { //タイトルのみでの検索
+            } else if (search_title != null) {
                 return publicBookManager.searchBooksByTitle(search_title);
-            } else if (search_account_id != null) { //アカウントIDのみでの検索
+            } else if (search_account_id != null) {
                 return publicBookManager.searchBooksByAccount(search_account_id);
-            } else { //タイトルもアカウントIDもない場合(すべての本を返す)
+            } else {
                 return publicBookManager.getAllPublicBooks();
             }
-        } else { //ソートする場合
-                if(search_title != null && search_account_id != null) { //タイトルとアカウントIDでの検索
+        } else {
+                if(search_title != null && search_account_id != null) {
                     return publicBookManager.searchBooksByTitleAndAccount(search_title, search_account_id, sort_by);
-                } else if(search_title != null) { //タイトルのみでの検索
+                } else if(search_title != null) {
                     return publicBookManager.searchBooksByTitle(search_title, sort_by);
-                } else if(search_account_id != null) { //アカウントIDのみでの検索
+                } else if(search_account_id != null) {
                     return publicBookManager.searchBooksByAccount(search_account_id, sort_by);
-                } else { //タイトルもアカウントIDもない場合(すべての本を返す)
+                } else {
                     return publicBookManager.getAllPublicBooks();
                 }
             }