/*
 * Copyright 2016 LINE Corporation
 *
 * LINE Corporation licenses this file to you under the Apache License,
 * version 2.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at:
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */

package com.linecorp.bot.model.event.postback;

import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;

import lombok.Value;

/**
 * Content of the postback event.
 */
@Value
public class PostbackContent {
    /**
     * Postback data
     */
    private final String data;
    private final Object params;

    @JsonCreator
    public PostbackContent(
            @JsonProperty("data") String data,
            @JsonProperty("params") Object params) {
        this.data = data;
        this.params = params;
    }
}

@@ -675,16 +675,39 @@
 tback;%0A%0A
+import java.util.Map;%0A%0A
 import c
@@ -994,22 +994,35 @@
 e final 
-Object
+Map%3CString, String%3E
  params;
@@ -1155,14 +1155,27 @@
 s%22) 
-Object
+Map%3CString, String%3E
  par

Change PostbackContent#params type to Map<String, String>