com.google.java.wob.ObjectListServlet.java Source code

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Here is the source code for com.google.java.wob.ObjectListServlet.java

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/*
 * Copyright 2013 Google Inc. All Rights Reserved.
 *
 * Licensed 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.google.java.wob;

import com.google.api.client.googleapis.json.GoogleJsonResponseException;
import com.google.api.client.json.GenericJson;
import com.google.api.client.json.JsonFactory;
import com.google.api.client.json.gson.GsonFactory;
import com.google.api.services.walletobjects.Walletobjects;
import com.google.api.services.walletobjects.model.GenericObjectListResponse;
import com.google.api.services.walletobjects.model.LoyaltyObjectListResponse;
import com.google.api.services.walletobjects.model.OfferObjectListResponse;
import com.google.common.base.Strings;
import com.google.gson.JsonArray;
import com.google.gson.JsonParser;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Logger;

import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Uses a wallet class id in order to retrieve objects of that class.
 */
public class ObjectListServlet extends HttpServlet {
    private static final Logger log = Logger.getLogger(ObjectListServlet.class.getName());

    @Override
    public void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {

        resp.setContentType("application/json; charset=utf-8");

        // Add all objects of kind "kind" and with class id "id"
        String kind = req.getParameter("kind");
        String id = req.getParameter("id");
        if (Strings.isNullOrEmpty(kind) || Strings.isNullOrEmpty(id)) {
            log.warning("Unable to retrieve objects without both kind and id");
            resp.getWriter().write(ClientMethods.createError(null));
            return;
        }

        String issuerId;
        try {
            issuerId = id.substring(0, id.indexOf("."));
        } catch (StringIndexOutOfBoundsException e) {
            log.warning("Invalid issuer id");
            resp.getWriter().write(ClientMethods.createError(null));
            return;
        }

        Walletobjects client = ClientMethods.getClientForId(issuerId);
        if (client == null) {
            log.warning("Unable to get client for issuer id " + issuerId + ".");
            resp.getWriter().write(ClientMethods.createError(null));
            return;
        }

        List<GenericJson> objList = new ArrayList<GenericJson>();
        GenericJson theClass = null;
        try {
            if (kind.contains("offer")) {
                // Attempt to list objects
                OfferObjectListResponse offerList = client.offerobject().list(id).execute();
                // If no objects exist, retrieve the class
                if (offerList.getResources() != null) {
                    objList.addAll(offerList.getResources());
                } else {
                    theClass = client.offerclass().get(id).execute();
                }
            } else if (kind.contains("loyalty")) {
                // Attempt to list objects
                LoyaltyObjectListResponse loyaltyList = client.loyaltyobject().list(id).execute();
                // If no objects exist, retrieve the class
                if (loyaltyList.getResources() != null) {
                    objList.addAll(loyaltyList.getResources());
                } else {
                    theClass = client.loyaltyclass().get(id).execute();
                }
            } else if (kind.contains("generic")) {
                // Attempt to list objects
                GenericObjectListResponse genericList = client.genericobject().list(id).execute();
                // If no objects exist, retrieve the class
                if (genericList.getResources() != null) {
                    objList.addAll(genericList.getResources());
                } else {
                    theClass = client.genericclass().get(id).execute();
                }
            } else {
                log.warning("Unable to retrieve objects with invalid kind " + kind + ".");
                resp.getWriter().write(ClientMethods.createError(null));
                return;
            }
        } catch (GoogleJsonResponseException e) {
            log.warning("Object list failed: " + e.getMessage());
            resp.getWriter().write(ClientMethods.createError("Something went wrong, please refresh and try again"));
            return;
        }

        JsonFactory jsonFactory = new GsonFactory();
        if (objList.size() > 0) {
            // Write the object's JSON as a list for client side
            // gson.toJson cannot be used due to differences in how the JSON is created
            JsonArray array = new JsonArray();
            JsonParser parser = new JsonParser();
            for (int i = 0; i < objList.size(); i++) {
                GenericJson theObj = objList.get(i);
                theObj.setFactory(jsonFactory);
                array.add(parser.parse(theObj.toString()));
            }
            resp.getWriter().write(array.toString());
        } else {
            // Write the class if there are no objects present so that the user
            // may still create an object and have a class to build on top of
            theClass.setFactory(jsonFactory);
            resp.getWriter().write(theClass.toString());
        }
    }
}