diff --git a/src/main/java/org/ntlab/amaryllis/server/entities/Account.java b/src/main/java/org/ntlab/amaryllis/server/entities/Account.java
index c5d5fff..424e4e9 100644
--- a/src/main/java/org/ntlab/amaryllis/server/entities/Account.java
+++ b/src/main/java/org/ntlab/amaryllis/server/entities/Account.java
@@ -1,6 +1,7 @@
 package org.ntlab.amaryllis.server.entities;
 
 import com.fasterxml.jackson.annotation.JsonIgnore;
+import org.ntlab.amaryllis.server.models.Accounts;
 
 import java.util.ArrayList;
 import java.util.UUID;
@@ -30,6 +31,8 @@
     }
 
     public void setUid(String uid) {
+        Accounts.getInstance().getMap().remove(getUid());
+        Accounts.getInstance().getMap().put(uid,this);
         this.uid = uid;
     }
 
diff --git a/src/main/java/org/ntlab/amaryllis/server/entities/LoginJson.java b/src/main/java/org/ntlab/amaryllis/server/entities/LoginJson.java
index 2ee4688..d184062 100644
--- a/src/main/java/org/ntlab/amaryllis/server/entities/LoginJson.java
+++ b/src/main/java/org/ntlab/amaryllis/server/entities/LoginJson.java
@@ -2,7 +2,7 @@
 
 import java.util.UUID;
 
-public class LoginJson extends AbstractJson {
+public class LoginJson  {
     private String message;
     private String token;
 
diff --git a/src/main/java/org/ntlab/amaryllis/server/models/Accounts.java b/src/main/java/org/ntlab/amaryllis/server/models/Accounts.java
index 3eb5348..02c3b62 100644
--- a/src/main/java/org/ntlab/amaryllis/server/models/Accounts.java
+++ b/src/main/java/org/ntlab/amaryllis/server/models/Accounts.java
@@ -3,12 +3,12 @@
 import com.fasterxml.jackson.annotation.JsonProperty;
 import org.ntlab.amaryllis.server.entities.Account;
 
+import javax.ws.rs.WebApplicationException;
 import java.util.ArrayList;
 import java.util.HashMap;
 
 public class Accounts {
     private static Accounts theInstance = null;
-    private ArrayList<Account> accounts = new ArrayList<Account>();
     private HashMap<String,Account> accountHashMap=new HashMap<>();
 
     public static Accounts getInstance() {
@@ -24,33 +24,62 @@
     }
 
     public Account getAccount(String uid) {
-        for (Account a : accounts) {
-            if (a.getUid().equals(uid)) return a;
-        }
-        return null;
+
+        return accountHashMap.get(uid);
+
     }
     public Account getAccountByName(String name){
-        for (Account a : accounts) {
-            if (a.getName().equals(name)) return a;
+
+        for(String key : accountHashMap.keySet()){
+            Account a=accountHashMap.get(key);
+            if(a.getName().equals(name))return a;
         }
         return null;
-
     }
 
     public boolean isRegisteredName(String name) {
-
-        for (Account a : accounts) {
-            if (a.getName().equals(name)) return true;
+        for(String key : accountHashMap.keySet()){
+            Account a=accountHashMap.get(key);
+            if(a.getName().equals(name))return true;
         }
         return false;
     }
+    /**
+     *パスワードが一致しているかを判定するメソッド
+     * @param uid 判定したいアカウントのuid
+     * @param password 入力されたパスワード
+     * @return パスワードが一致していればtrue
+     */
+    public boolean matchesPassword(String uid,String password){
+        return getAccount(uid).getPassword().equals(password);
+    }
+    /**
+     *トークンが一致しているかを判定するメソッド.
+     * (passwordを必要としない通信用のメソッド)
+     * @param uid 判定したいアカウントのuid
+     * @param token 入力されたトークン
+     * @return トークンが一致していればtrue
+     */
+    public boolean matchesToken(String uid,String token){
+        return getAccount(uid).getToken().equals(token);
+    }
+    /**
+     *メソッドに渡されたuidが同一かを判定するメソッド.
+     * (自分自身をフォローしないようにする為に実装しました)
+     * @param uid あるアカウントのuid
+     * @param targetUid 対象のuid
+     * @return uidが同一であればtrue
+     */
+    public boolean isSameUid(String uid,String targetUid){
+        return getAccount(uid).equals(targetUid);
+    }
 
-    public ArrayList<Account> getList() {
-        return accounts;
+
+    public HashMap<String,Account> getMap(){
+        return accountHashMap;
     }
 
     public void addAccount(Account account) {
-        accounts.add(account);
 
         accountHashMap.put(account.getUid(),account);
     }
@@ -62,13 +91,29 @@
     }
 
     public void removeAccount(String uid) {
-        int index=0;
-        for(Account a:accounts){
-            if(a.getUid().equals(uid))accounts.remove(index);
-            index++;
-        }
         accountHashMap.remove(uid);
     }
 
+    /**
+     *誰かをフォローした時に実行するメソッド.
+     * @param fromUid フォローを実行したアカウントのuid
+     * @param toUid 　フォローされたアカウントのuid
+     */
+    public void followAccount(String fromUid,String toUid){
+        getAccount(fromUid).getFollowings().add(toUid);
+        getAccount(toUid).getFollowers().add(fromUid);
+    }
+
+    /**
+     *誰かのフォローを外した時に実行するメソッド.
+     * @param fromUid フォロー外しを実行したアカウントのuid
+     * @param toUid 　フォローを外されたアカウントのuid
+     */
+    public void unfollowAccount(String fromUid,String toUid){
+        getAccount(fromUid).getFollowings().remove(toUid);
+        getAccount(toUid).getFollowers().remove(fromUid);
+    }
+
+
 
 }
diff --git a/src/main/java/org/ntlab/amaryllis/server/resources/AccountsRest.java b/src/main/java/org/ntlab/amaryllis/server/resources/AccountsRest.java
index 7903db8..164aa92 100644
--- a/src/main/java/org/ntlab/amaryllis/server/resources/AccountsRest.java
+++ b/src/main/java/org/ntlab/amaryllis/server/resources/AccountsRest.java
@@ -25,21 +25,20 @@
     private Accounts accounts = Accounts.getInstance();
 
     AccountsRest() {
-
         /**
          * テスト用
          * */
         {
-            createAccount("name", "pass");
-            Account a = accounts.getList().get(0);
-            a.setUid("test");
+            SignUpJson sj=createAccount("name", "pass");
+            accounts.getAccountByName("name").setUid("test");
+
         }
     }
 
     @GET
     @Produces(MediaType.APPLICATION_JSON)
-    public ArrayList<Account> getAccounts() {
-        return accounts.getList();
+    public Collection<Account> getAccounts() {
+        return accounts.getMap().values();
     }
 
     @POST
@@ -64,14 +63,17 @@
 
     @PUT
     @Produces(MediaType.APPLICATION_JSON)
-    public LoginJson loginByName(@FormParam("name") String name, @FormParam("password") String password) {
+    public SignUpJson loginByName(@FormParam("name") String name, @FormParam("password") String password) {
         Account account = accounts.getAccountByName(name);
 
-        if (password.equals(account.getPassword())) {
+        if (accounts.matchesPassword(account.getUid(),password)) {
 
-            account.setToken(UUID.randomUUID().toString());
-            LoginJson loginJson = new LoginJson("success");
-            return loginJson;
+
+            SignUpJson signUpJson = new SignUpJson();
+            signUpJson.setUid(account.getUid());
+            signUpJson.setMessage("success");
+            account.setToken(signUpJson.getToken());
+            return signUpJson;
 
         } else {
             throw new WebApplicationException(400);
@@ -84,10 +86,11 @@
     public LoginJson login(@PathParam("uid") String uid, @FormParam("password") String password) {
         Account account = accounts.getAccount(uid);
 
-        if (password.equals(account.getPassword())) {
+        if (accounts.matchesPassword(uid,password)) {
 
-            account.setToken(UUID.randomUUID().toString());
+            //account.setToken(UUID.randomUUID().toString());
             LoginJson loginJson = new LoginJson("success");
+            account.setToken(loginJson.getToken());
             return loginJson;
 
         } else {
@@ -107,4 +110,40 @@
 
     }
 
+    @Path("/{uid}")
+    @DELETE
+    @Produces(MediaType.APPLICATION_JSON)
+    public MessageJson deleteAccount(@PathParam("uid")String uid,@FormParam("password")String password){
+        if(accounts.matchesPassword(uid,password)) {
+            accounts.removeAccount(uid);
+            return new MessageJson("success");
+        }
+        throw new WebApplicationException(400);
+    }
+    @Path("/{uid}/followings")
+    @GET
+    @Produces(MediaType.APPLICATION_JSON)
+    public ArrayList<String> getFollowings(@PathParam("uid")String uid){
+        return getAccount(uid).getFollowings();
+    }
+    @Path("/{uid}/followings")
+    @POST
+    @Produces(MediaType.APPLICATION_JSON)
+    public MessageJson addFollowings(@PathParam("uid")String uid,@FormParam("token")String token,@FormParam("newFollow")String newFollow){
+        if(accounts.matchesToken(uid,token)&&!accounts.isSameUid(uid,newFollow)) {
+            accounts.followAccount(uid,newFollow);
+            return new MessageJson("success");
+        }
+        throw new WebApplicationException(400);
+    }
+    @Path("/{uid}/followings")
+    @DELETE
+    @Produces(MediaType.APPLICATION_JSON)
+    public MessageJson deleteFollowings(@PathParam("uid")String uid,@FormParam("token")String token,@FormParam("deleteFollow")String deleteFollow){
+        if(accounts.matchesToken(uid,token)&&!accounts.isSameUid(uid,deleteFollow)) {
+           accounts.unfollowAccount(uid,deleteFollow);
+            return new MessageJson("success");
+        }
+        throw new WebApplicationException(400);
+    }
 }
\ No newline at end of file