Java EnumMap.containsKey方法代碼示例

import java.util.EnumMap; //導入方法依賴的package包/類
/**
 * Calculates mask entries required for the ACL.  Mask calculation is performed
 * separately for each scope: access and default.  This method is responsible
 * for handling the following cases of mask calculation:
 * 1. Throws an exception if the caller attempts to remove the mask entry of an
 *   existing ACL that requires it.  If the ACL has any named entries, then a
 *   mask entry is required.
 * 2. If the caller supplied a mask in the ACL spec, use it.
 * 3. If the caller did not supply a mask, but there are ACL entry changes in
 *   this scope, then automatically calculate a new mask.  The permissions of
 *   the new mask are the union of the permissions on the group entry and all
 *   named entries.
 *
 * @param aclBuilder ArrayList<AclEntry> containing entries to build
 * @param providedMask EnumMap<AclEntryScope, AclEntry> mapping each scope to
 *   the mask entry that was provided for that scope (if provided)
 * @param maskDirty EnumSet<AclEntryScope> which contains a scope if the mask
 *   entry is dirty (added or deleted) in that scope
 * @param scopeDirty EnumSet<AclEntryScope> which contains a scope if any entry
 *   is dirty (added or deleted) in that scope
 * @throws AclException if validation fails
 */
private static void calculateMasks(List<AclEntry> aclBuilder,
    EnumMap<AclEntryScope, AclEntry> providedMask,
    EnumSet<AclEntryScope> maskDirty, EnumSet<AclEntryScope> scopeDirty)
    throws AclException {
  EnumSet<AclEntryScope> scopeFound = EnumSet.noneOf(AclEntryScope.class);
  EnumMap<AclEntryScope, FsAction> unionPerms =
    Maps.newEnumMap(AclEntryScope.class);
  EnumSet<AclEntryScope> maskNeeded = EnumSet.noneOf(AclEntryScope.class);
  // Determine which scopes are present, which scopes need a mask, and the
  // union of group class permissions in each scope.
  for (AclEntry entry: aclBuilder) {
    scopeFound.add(entry.getScope());
    if (entry.getType() == GROUP || entry.getName() != null) {
      FsAction scopeUnionPerms = Objects.firstNonNull(
        unionPerms.get(entry.getScope()), FsAction.NONE);
      unionPerms.put(entry.getScope(),
        scopeUnionPerms.or(entry.getPermission()));
    }
    if (entry.getName() != null) {
      maskNeeded.add(entry.getScope());
    }
  }
  // Add mask entry if needed in each scope.
  for (AclEntryScope scope: scopeFound) {
    if (!providedMask.containsKey(scope) && maskNeeded.contains(scope) &&
        maskDirty.contains(scope)) {
      // Caller explicitly removed mask entry, but it's required.
      throw new AclException(
        "Invalid ACL: mask is required and cannot be deleted.");
    } else if (providedMask.containsKey(scope) &&
        (!scopeDirty.contains(scope) || maskDirty.contains(scope))) {
      // Caller explicitly provided new mask, or we are preserving the existing
      // mask in an unchanged scope.
      aclBuilder.add(providedMask.get(scope));
    } else if (maskNeeded.contains(scope) || providedMask.containsKey(scope)) {
      // Otherwise, if there are maskable entries present, or the ACL
      // previously had a mask, then recalculate a mask automatically.
      aclBuilder.add(new AclEntry.Builder()
        .setScope(scope)
        .setType(MASK)
        .setPermission(unionPerms.get(scope))
        .build());
    }
  }
}