diff --git a/src/main/java/com/example/cosmos_serversb/jsons/GroupJson.java b/src/main/java/com/example/cosmos_serversb/jsons/GroupJson.java
new file mode 100644
index 0000000..9557209
--- /dev/null
+++ b/src/main/java/com/example/cosmos_serversb/jsons/GroupJson.java
@@ -0,0 +1,90 @@
+//このクラスは仮です
+package com.example.cosmos_serversb.jsons;
+
+import com.example.cosmos_serversb.entities.Group;
+import com.example.cosmos_serversb.entities.Request;
+import com.example.cosmos_serversb.entities.User;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Set;
+
+public class GroupJson {
+    private String gId;
+    private String uri, name;
+    private Map<String, String> members = new HashMap<>();//HashSetでいいのかな？
+    private Map<String, String> requests = new HashMap<>();
+
+    public GroupJson(Group group){
+        setgId(group.getgId());
+        setUri(group.getUri());
+        setName(group.getName());
+        changeMembersMap(group.getMembers());
+        changeRequestsMap(group.getRequests());
+    }
+
+    public String getgId() {
+        return gId;
+    }
+
+    private void setgId(String gId) {
+        this.gId = gId;
+    }
+
+    public String getUri() {
+        return uri;
+    }
+
+    private void setUri(String uri){
+        this.uri = uri;
+    }
+
+    public String getUriByGid(String gId){
+        return uri;
+    }
+
+    private void setName(String name){
+        this.name = name;
+    }
+
+    public String getName(){
+        return name;
+    }
+
+    public String getNameByGid(String gId){
+        return name;
+    }
+
+    public Map<String, String> getMembers() {
+        return members;
+    }
+
+    public void setMembers(Map<String, String> members) {
+        this.members = members;
+    }
+
+    public Map<String, String> getRequests() {
+        return requests;
+    }
+
+    public void setRequests(Map<String, String> requests) {
+        this.requests = requests;
+    }
+
+    private void changeMembersMap(Set set){
+        for ( User user : (Set<User>) set ) {
+            members.put(user.getuId(), getUri());
+        }
+    }
+
+    private void changeRequestsMap(Set set){
+        for ( Request request : (Set<Request>) set ) {
+            requests.put(request.getrId(), getUri());
+        }
+    }
+
+
+
+
+}
+