TokenResponseException：401未授權當試圖訪問谷歌聯繫人Api

Question

我想連接到谷歌聯繫人api來訪問我的聯繫人/保存在谷歌的人，但它會拋出TokenResponseException：401未授權。我對Google Oauth2.0有點新穎。我已經根據需要將服務帳戶密鑰文件下載到我的項目根目錄。

下面是代碼：

import com.google.api.client.googleapis.auth.oauth2.GoogleCredential; 
import com.google.api.client.googleapis.javanet.GoogleNetHttpTransport; 
import com.google.api.client.http.HttpTransport; 
import com.google.api.client.json.jackson2.JacksonFactory; 
import com.google.gdata.client.contacts.ContactsService; 
import java.io.IOException; 
import java.security.GeneralSecurityException; 
import java.util.Arrays; 

public class Connector { 
private static ContactsService contactService = null; 
    private static HttpTransport httpTransport; 

    private static final String APPLICATION_NAME = "example"; 
    private static final String SERVICE_ACCOUNT_EMAIL = "example_mail@example-166608.iam.gserviceaccount.com"; 
    private static final java.util.List<String> SCOPE = Arrays.asList("https://www.google.com/m8/feeds/"); 

    private Connector() { 
     // explicit private no-args constructor 
    } 

    public static void main(String[] args) { 
     System.out.println(getInstance()); 
    } 

    public static ContactsService getInstance() { 
     if (contactService == null) { 
      try { 
       contactService = connect(); 
      } catch (GeneralSecurityException e) { 
       e.printStackTrace(); 
      } catch (IOException e) { 
       e.printStackTrace(); 
      } 
     } 

     return contactService; 
    } 

    private static ContactsService connect() throws GeneralSecurityException, IOException { 
     httpTransport = GoogleNetHttpTransport.newTrustedTransport(); 

     java.io.File p12File = new java.io.File("example-e8135faedf4e.p12"); 

     // @formatter:off 
     GoogleCredential credential = new GoogleCredential.Builder() 
       .setTransport(httpTransport) 
       .setJsonFactory(JacksonFactory.getDefaultInstance()) 
       .setServiceAccountId(SERVICE_ACCOUNT_EMAIL) 
       .setServiceAccountScopes(SCOPE) 
       .setServiceAccountPrivateKeyFromP12File(p12File) 
       .setServiceAccountUser("example@gmail.com") 
       .build(); 
     // @formatter:on 

     if (!credential.refreshToken()) { 
      throw new RuntimeException("Failed OAuth to refresh the token"); 
     } 

     ContactsService myService = new ContactsService(APPLICATION_NAME); 
     myService.setOAuth2Credentials(credential); 

     return myService; 
    } 
} 

但是以下異常被拋出：

com.google.api.client.auth.oauth2.TokenResponseException：401未經授權
空
com.google.api.client.auth.oauth2.TokenResponseException.from（TokenResponseException.java:105） at com.google.api.client.auth.oauth2.TokenRequest.executeU nparsed（TokenRequest.java:287） at com.google.api.client.auth.oauth2.TokenRequest.execute（TokenRequest.java:307） at com.google.api.client.googleapis.auth.oauth2。 GoogleCredential.executeRefreshToken（GoogleCredential.java:384） 在 com.google.api.client.auth.oauth2.Credential.refreshToken（Credential.java:489） 在Connector.connect（Connector.java:58）在 連接器.getInstance（Connector.java:31）在 Connector.main（Connector.java:25）BUILD SUCCESSFUL（總時間：9秒 ）

Answer 1

從這個基於,TokenResponseException可能由許多事情引起，如無效的客戶端ID，客戶端密鑰或範圍以及刷新令牌過度使用。它還聲明here另一個可能的來源爲「401未授權」例外是離開credential.refreshToken()。該調用是必要的，以將訪問代碼寫入參考。

可能還有幫助的其他參考：401 response when athenticating via Service Account and OAuth2 to GoogleDrive