JsonHelper.java

/*******************************************************************************
 * Copyright (c) 2012-2017 Codenvy, S.A.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *   Codenvy, S.A. - initial API and implementation
 *******************************************************************************/
package org.eclipse.che.ide.json;

import com.google.gwt.json.client.JSONArray;
import com.google.gwt.json.client.JSONObject;
import com.google.gwt.json.client.JSONParser;
import com.google.gwt.json.client.JSONString;
import com.google.gwt.json.client.JSONValue;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * @author <a href="mailto:vparfonov@codenvy.com">Vitaly Parfonov</a>
 */
public class JsonHelper {

    public static String toJson(Map<String, String> map) {
        String json = "";
        if (map != null && !map.isEmpty()) {
            JSONObject jsonObj = new JSONObject();
            for (Map.Entry<String, String> entry: map.entrySet()) {
                jsonObj.put(entry.getKey(), new JSONString(entry.getValue()));
            }
            json = jsonObj.toString();
        }
        return json;
    }

    public static Map<String, String> toMap(String jsonStr) {
        Map<String, String> map = new HashMap<String, String>();

        JSONValue parsed = JSONParser.parseStrict(jsonStr);
        JSONObject jsonObj = parsed.isObject();
        if (jsonObj != null) {
            for (String key : jsonObj.keySet()) {
                JSONValue jsonValue = jsonObj.get(key);
                JSONString jsonString = jsonValue.isString();
                // if the json value is a string, set the unescaped value, else set the json representation of the value
                String stringValue = (jsonString == null) ? jsonValue.toString() : jsonString.stringValue();
                map.put(key, stringValue);
            }
        }

        return map;
    }

    public static Map<String, List<String>> toMapOfLists(String jsonStr) {
        Map<String, List<String>> map = new HashMap<>();

        JSONValue parsed = JSONParser.parseStrict(jsonStr);
        JSONObject jsonObj = parsed.isObject();
        if (jsonObj != null) {
            for (String key : jsonObj.keySet()) {
                JSONValue jsonValue = jsonObj.get(key);
                JSONArray jsonArray = jsonValue.isArray();

                List<String> values = new ArrayList<>();
                for (int i = 0; i < jsonArray.size(); i++) {
                    values.add(jsonArray.get(i).isString().stringValue());
                }
                map.put(key, values);
            }
        }

        return map;
    }

    //TODO: find a way to avoid those util methods here.

    /** Returns message or result of it parse if the message is json. */
    public static String parseJsonMessage(String parsedMessage) {
        try {
            //parsed message
            JSONValue message = JSONParser.parseStrict(parsedMessage).isObject().get("message");
            return message.isString().stringValue();
        } catch (Exception e) {
            //not found json in message
            return parsedMessage;
        }
    }

    /** Returns message or result of it parse if the message is json. */
    public static Map<String, String> parseErrorAttributes(String parsedMessage) {
        try {
            //parsed message
            JSONValue message = JSONParser.parseStrict(parsedMessage).isObject().get("attributes");
            return toMap(message.isObject().toString());
        } catch (Exception e) {
            //not found json in message
            return Collections.emptyMap();
        }
    }

    /** Returns message or result of it parse if the message is json. */
    public static int parseErrorCode(String parsedMessage) {
        try {
            //parsed message
            JSONValue message = JSONParser.parseStrict(parsedMessage).isObject().get("errorCode");
            return new Double(message.isNumber().doubleValue()).intValue();
        } catch (Exception e) {
            //not found json in message
            return -1;
        }
    }

}