fix: make calendar field private and modify it through builder

Author: ivan-f-n

oauth2_http/java/com/google/auth/oauth2/ImpersonatedCredentials.java

@@ -111,7 +111,7 @@ public class ImpersonatedCredentials extends GoogleCredentials
 
  private transient HttpTransportFactory transportFactory;
 
- @VisibleForTesting transient Calendar calendar = Calendar.getInstance();
+ private transient Calendar calendar;
 
  /**
  * @param sourceCredentials the source credential used to acquire the impersonated credentials. It
@@ -432,6 +432,25 @@ public GoogleCredentials createScoped(Collection<String> scopes) {
  .build();
  }
 
+ /**
+ * Clones the impersonated credentials with a new calendar.
+ *
+ * @param calendar the calendar that will be used by the new ImpersonatedCredentials instance when
+ * parsing the received expiration time of the refreshed access token
+ * @return the cloned impersonated credentials with the given custom calendar
+ */
+ public ImpersonatedCredentials createWithCustomCalendar(Calendar calendar) {
+ return toBuilder()
+ .setScopes(this.scopes)
+ .setLifetime(this.lifetime)
+ .setDelegates(this.delegates)
+ .setHttpTransportFactory(this.transportFactory)
+ .setQuotaProjectId(this.quotaProjectId)
+ .setIamEndpointOverride(this.iamEndpointOverride)
+ .setCalendar(calendar)
+ .build();
+ }
+
  @Override
  protected Map<String, List<String>> getAdditionalHeaders() {
  Map<String, List<String>> headers = super.getAdditionalHeaders();
@@ -454,6 +473,7 @@ private ImpersonatedCredentials(Builder builder) {
  this.quotaProjectId = builder.quotaProjectId;
  this.iamEndpointOverride = builder.iamEndpointOverride;
  this.transportFactoryClassName = this.transportFactory.getClass().getName();
+ this.calendar = builder.getCalendar();
  if (this.delegates == null) {
  this.delegates = new ArrayList<String>();
  }
@@ -610,6 +630,7 @@ public static class Builder extends GoogleCredentials.Builder {
  private HttpTransportFactory transportFactory;
  private String quotaProjectId;
  private String iamEndpointOverride;
+ private Calendar calendar = Calendar.getInstance();
 
  protected Builder() {}
 
@@ -682,6 +703,15 @@ public Builder setIamEndpointOverride(String iamEndpointOverride) {
  return this;
  }
 
+ public Builder setCalendar(Calendar calendar) {
+ this.calendar = calendar;
+ return this;
+ }
+
+ public Calendar getCalendar() {
+ return this.calendar;
+ }
+
  public ImpersonatedCredentials build() {
  return new ImpersonatedCredentials(this);
  }

oauth2_http/javatests/com/google/auth/oauth2/ImpersonatedCredentialsTest.java

@@ -567,7 +567,6 @@ void refreshAccessToken_delegates_success() throws IOException, IllegalStateExce
 
  @Test
  void refreshAccessToken_GMT_dateParsedCorrectly() throws IOException, IllegalStateException {
-
  Calendar c = Calendar.getInstance();
  c.add(Calendar.SECOND, VALID_LIFETIME);
 
@@ -576,14 +575,15 @@ void refreshAccessToken_GMT_dateParsedCorrectly() throws IOException, IllegalSta
  mockTransportFactory.transport.setExpireTime(getFormattedTime(c.getTime()));
  ImpersonatedCredentials targetCredentials =
  ImpersonatedCredentials.create(
- sourceCredentials,
- IMPERSONATED_CLIENT_EMAIL,
- null,
- IMMUTABLE_SCOPES_LIST,
- VALID_LIFETIME,
- mockTransportFactory);
- // Set system timezone to GMT
- targetCredentials.calendar = Calendar.getInstance(TimeZone.getTimeZone("GMT"));
+ sourceCredentials,
+ IMPERSONATED_CLIENT_EMAIL,
+ null,
+ IMMUTABLE_SCOPES_LIST,
+ VALID_LIFETIME,
+ mockTransportFactory)
+ .createWithCustomCalendar(
+ // Set system timezone to GMT
+ Calendar.getInstance(TimeZone.getTimeZone("GMT")));
 
  assertEquals(
  c.getTime().toInstant().truncatedTo(ChronoUnit.SECONDS).toEpochMilli(),
@@ -592,7 +592,6 @@ void refreshAccessToken_GMT_dateParsedCorrectly() throws IOException, IllegalSta
 
  @Test
  void refreshAccessToken_nonGMT_dateParsedCorrectly() throws IOException, IllegalStateException {
-
  Calendar c = Calendar.getInstance();
  c.add(Calendar.SECOND, VALID_LIFETIME);
 
@@ -601,14 +600,15 @@ void refreshAccessToken_nonGMT_dateParsedCorrectly() throws IOException, Illegal
  mockTransportFactory.transport.setExpireTime(getFormattedTime(c.getTime()));
  ImpersonatedCredentials targetCredentials =
  ImpersonatedCredentials.create(
- sourceCredentials,
- IMPERSONATED_CLIENT_EMAIL,
- null,
- IMMUTABLE_SCOPES_LIST,
- VALID_LIFETIME,
- mockTransportFactory);
- // Set system timezone to one different than GMT
- targetCredentials.calendar = Calendar.getInstance(TimeZone.getTimeZone("America/Los_Angeles"));
+ sourceCredentials,
+ IMPERSONATED_CLIENT_EMAIL,
+ null,
+ IMMUTABLE_SCOPES_LIST,
+ VALID_LIFETIME,
+ mockTransportFactory)
+ .createWithCustomCalendar(
+ // Set system timezone to one different than GMT
+ Calendar.getInstance(TimeZone.getTimeZone("America/Los_Angeles")));
 
  assertEquals(
  c.getTime().toInstant().truncatedTo(ChronoUnit.SECONDS).toEpochMilli(),