Google Calendar API V3 Java：无法对日历使用“主要”：get答案

【问题标题】：Google Calendar API V3 Java: Unable to use 'primary' for Calendars:getGoogle Calendar API V3 Java：无法对日历使用“主要”：get
【发布时间】：2015-03-21 10:16:16
【问题描述】：

我对 Google Calendar V3 Java API 非常陌生。我正在使用 Eclipse 使用 Java 进行开发。到目前为止，我已经成功：

获取特定 Google 帐户中所有不同日历的 CalendarList 汇总
使用日历 ID 作为标识符，获取特定 Google 帐户中仅一个日历的 CalendarList 摘要。

现在，我想探索 Calendars 而不是 CalendarList。我尝试实现 Calendars get 方法。但是，我面临一个问题。

Google 的教程将此作为示例代码：

Calendar calendar = service.calendars().get('primary').execute();
System.out.println(calendar.getSummary());

但是，Eclipse 突出显示“主要”并说它是“无效字符常量”。

我尝试将其改为字符串“primary”，Eclipse 突出显示整行，说存在类型不匹配。

我非常不确定 Google 教程中给出的“主”字符串数组的真正期望是什么。我应该用主日历的日历 ID 替换它吗？我尝试过，无论是作为字符串还是作为字符数组，但我不断从 Eclipse 中获取编译错误。

这是我使用的代码：

public static void getCalendarSummary(String calendarID, Calendar service) throws IOException{ 
    Calendar calendar = service.calendars().get("primary").execute();
    System.out.println(calendar.getSummary());
}

有人能告诉我我做错了什么吗？我搜索了所有谷歌教程参考，但未能得出结论。谢谢你。

这是 Google 教程的链接：https://developers.google.com/google-apps/calendar/v3/reference/calendars/get?hl=fr

编辑：运行程序后，这就是我得到的。前两种方法工作正常并提供正确的结果。但是，我收到有关方法的错误 - 未解决的编译问题 - 无效字符常量。以下是完整的回复：

Go to the following address:
https://accounts.google.com/o/oauth2/auth?client_id=369332843116-gr8ct1guerlf1fudpgivfjv43h0oleip.apps.googleusercontent.com&redirect_uri=urn:ietf:wg:oauth:2.0:oob&response_type=code&scope=https://www.googleapis.com/auth/calendar
What is the 'code' url parameter?
4/LvuhiV9Qb_gzCgXmkveIw2kfbOFA.gtXwZ0hWA0QRcp7tdiljKKa1LV4tkQI
GooCal
ID: quolc4s8etou3ea1ca071ud9tk@group.calendar.google.com
Summary: DEADLINES
ID: u8jsu7vcrbh9okbj4tbs1nev74@group.calendar.google.com
Summary: Calendar 1
ID: gfof3i5u8pdn3esjk3mbmgiop8@group.calendar.google.com
Summary: LightUp
ID: i.*****@gmail.com
Summary: Personal Events
ID: w*****@gmail.com
Summary: w*****@gmail.com
ID: horiq2vgch2cprklf58ntdvhd8@group.calendar.google.com
Summary: Team A********** - Orbital Project
ID: 2h4du2sgsu1t5p2238j2mbk77k@group.calendar.google.com
Summary: TechTouch - GG Fix
ID: i357fqqhffrf1fa9udcbn9sikc@group.calendar.google.com
Summary: GooCal
ID: en.singapore#holiday@group.v.calendar.google.com
Summary: Holidays in Singapore
Exception in thread "main" java.lang.Error: Unresolved compilation problem: 
    Invalid character constant

    at SimpleCalendarTest.getCalendarSummary(SimpleCalendarTest.java:100)
    at SimpleCalendarTest.main(SimpleCalendarTest.java:81)

这是我的全部代码，如果有帮助的话。 :)

import java.io.IOException;
import java.util.Collections;
import java.util.Scanner;
import java.util.Set;

import com.google.api.client.auth.oauth2.AuthorizationCodeFlow;
import com.google.api.client.auth.oauth2.AuthorizationCodeRequestUrl;
import com.google.api.client.auth.oauth2.AuthorizationCodeTokenRequest;
import com.google.api.client.auth.oauth2.Credential;
import com.google.api.client.auth.oauth2.TokenResponse;
import com.google.api.client.googleapis.auth.oauth2.GoogleAuthorizationCodeFlow;
import com.google.api.client.http.HttpRequestInitializer;
import com.google.api.client.http.HttpTransport;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.JsonFactory;
import com.google.api.client.json.jackson.JacksonFactory;
import com.google.api.services.calendar.Calendar;
import com.google.api.services.calendar.CalendarScopes;
import com.google.api.services.calendar.model.CalendarList;
import com.google.api.services.calendar.model.CalendarListEntry;
import com.google.api.services.calendar.model.*;


public class SimpleCalendarTest {
    public static void main(String[] args) throws IOException{
        //Two globals that will be used in each step.
        HttpTransport httpTransport = new NetHttpTransport();
        JsonFactory jsonFactory = new JacksonFactory();

        //Create the authorization code flow manager
        Set<String> scope = Collections.singleton(CalendarScopes.CALENDAR);
        String clientId = "xxxxxxx";
        String clientSecret = "xxxxxxx";

        //Use a factory pattern to create the code flow
        AuthorizationCodeFlow.Builder codeFlowBuilder = 
                new GoogleAuthorizationCodeFlow.Builder(
                        httpTransport, 
                        jsonFactory, 
                        clientId, 
                        clientSecret, 
                        scope
                );
        AuthorizationCodeFlow codeFlow = codeFlowBuilder.build();

        //set the code flow to use a dummy user
        //in a servlet, this could be the session id
        String userId = "ipeech";

        //"redirect" to the authentication url
        String redirectUri = "urn:ietf:wg:oauth:2.0:oob";
        AuthorizationCodeRequestUrl authorizationUrl = codeFlow.newAuthorizationUrl();
        authorizationUrl.setRedirectUri(redirectUri);
        System.out.println("Go to the following address:");
        System.out.println(authorizationUrl);

        //use the code that is returned as a url parameter
        //to request an authorization token
        System.out.println("What is the 'code' url parameter?");
        String code = new Scanner(System.in).nextLine();

        AuthorizationCodeTokenRequest tokenRequest = codeFlow.newTokenRequest(code);
        tokenRequest.setRedirectUri(redirectUri);
        TokenResponse tokenResponse = tokenRequest.execute();

        //Now, with the token and user id, we have credentials
        Credential credential = codeFlow.createAndStoreCredential(tokenResponse, userId);

        //Credentials may be used to initialize http requests
        HttpRequestInitializer initializer = credential;
        //and thus are used to initialize the calendar service
        Calendar.Builder serviceBuilder = new Calendar.Builder(
                httpTransport, jsonFactory, initializer);
        serviceBuilder.setApplicationName("GooCal");
        Calendar calendar = serviceBuilder.build();

        //get some data
        String calendarID = "xxxxxxxx@group.calendar.google.com";
        getCalendarListSummary(calendarID,calendar);
        getAllCalendarListSummary(calendar);
        getCalendarSummary(calendarID,calendar);
    }

    public static void getCalendarListSummary(String calendarID, Calendar calendar) throws IOException{
        CalendarListEntry calendarListEntry = calendar.calendarList().get(calendarID).execute();
        System.out.println(calendarListEntry.getSummary());
    }

    public static void getAllCalendarListSummary (Calendar calendar) throws IOException{
        Calendar.CalendarList.List listRequest = calendar.calendarList().list();
        CalendarList feed = listRequest.execute();
        for(CalendarListEntry entry:feed.getItems()){
            System.out.println("ID: " + entry.getId());
            System.out.println("Summary: " + entry.getSummary());
        }
    }


    public static void getCalendarSummary(String calendarID, Calendar service) throws IOException{ 
        Calendar calendar = service.calendars().get('primary').execute();
        System.out.println(calendar.getSummary());
    }
}

谢谢！ :)

编辑 2：当我将“primary”替换为“primary”时，这是我收到的错误消息。

What is the 'code' url parameter?
    4/LvuhiV9Qb_gzCgXmkveIw2kfbOFA.gtXwZ0hWA0QRcp7tdiljKKa1LV4tkQI
    GooCal
    ID: quolc4s8etou3ea1ca071ud9tk@group.calendar.google.com
    Summary: DEADLINES
    ID: u8jsu7vcrbh9okbj4tbs1nev74@group.calendar.google.com
    Summary: Calendar 1
    ID: gfof3i5u8pdn3esjk3mbmgiop8@group.calendar.google.com
    Summary: LightUp
    ID: i.*****@gmail.com
    Summary: Personal Events
    ID: w*****@gmail.com
    Summary: w*****@gmail.com
    ID: horiq2vgch2cprklf58ntdvhd8@group.calendar.google.com
    Summary: Team A********** - Orbital Project
    ID: 2h4du2sgsu1t5p2238j2mbk77k@group.calendar.google.com
    Summary: TechTouch - GG Fix
    ID: i357fqqhffrf1fa9udcbn9sikc@group.calendar.google.com
    Summary: GooCal
    ID: en.singapore#holiday@group.v.calendar.google.com
    Summary: Holidays in Singapore
Exception in thread "main" java.lang.Error: Unresolved compilation problems: 
    Type mismatch: cannot convert from com.google.api.services.calendar.model.Calendar to com.google.api.services.calendar.Calendar
    The method getSummary() is undefined for the type Calendar

    at SimpleCalendarTest.getCalendarSummary(SimpleCalendarTest.java:100)
    at SimpleCalendarTest.main(SimpleCalendarTest.java:81)

似乎存在类型不匹配。谢谢你的帮助！

编辑 3：将 import com.google.api.services.calendar.Calendar 替换为 com.google.api.services.calendar.model.Calendar 会导致其他问题。 Eclipse 强调用于初始化日历服务的代码存在问题。 Calendar.Builder 无法解析为类型。

Calendar.Builder serviceBuilder = new Calendar.Builder(
                httpTransport, jsonFactory, initializer);

当我运行时，我得到了这个错误。

Exception in thread "main" java.lang.Error: Unresolved compilation problems: 
    Calendar.Builder cannot be resolved to a type
    Calendar.Builder cannot be resolved to a type

    at SimpleCalendarTest.main(SimpleCalendarTest.java:73)

感谢您的帮助！

【问题讨论】：

代码看起来是合法的，请分享eclipse给你的信息。
我已经编辑了代码以包含 eclipse 给我的信息，并添加了我一直在使用的完整代码。感谢您的帮助！
酷，请将“primary”中的单引号替换为撇号“primary”，然后粘贴您收到的错误消息。这肯定是错误的，因为您只能对字符使用单引号，而不能对 Java 中的字符串使用。
我已经编辑了帖子以包含当我将“primary”替换为“primary”时 eclipse 给我的信息。存在类型不匹配。感谢您的帮助！

标签： java eclipse calendar google-calendar-api

【解决方案1】：

将此导入 com.google.api.services.calendar.Calendar 替换为 com.google.api.services.calendar.model.Calendar。

【讨论】：

当我这样做时，我当前的日历初始化程序似乎已经停止工作。我已经编辑了我的原始帖子以显示我在替换导入语句时遇到的错误。感谢您的帮助！
那就这样吧：com.google.api.services.calendar.model.Calendar calendar = service.calendars().get("primary").execute();
行得通！非常感谢你花时间帮助我，卢克。 :)

【解决方案2】：

在“primary”周围使用双引号而不是单引号 :) 单引号用于字符，如 Java 中的 'a'。
读取错误：“类型不匹配：无法从 com.google.api.services.calendar.model.Calendar 转换为 com.google.api.services.calendar.Calendar”。这是两个完全不同的类（注意包名），“日历”只是类名的一部分。

【讨论】：