code: public void setPermissionsFromString(final String value) {
          EnumSet<SharedAccessFilePermissions> initial = EnumSet.noneOf(SharedAccessFilePermissions.class);
          for (final char c : value.toCharArray()) {
              switch (c) {
                  case 'r':
                      initial.add(SharedAccessFilePermissions.READ);
                      break;
                  case 'c':
                      initial.add(SharedAccessFilePermissions.CREATE);
                      break;
                  case 'w':
                      initial.add(SharedAccessFilePermissions.WRITE);
                      break;
                  case 'd':
                      initial.add(SharedAccessFilePermissions.DELETE);
                      break;
                  case 'l':
                      initial.add(SharedAccessFilePermissions.LIST);
                      break;
                  default:
                      throw new IllegalArgumentException("value");
              }
          }
          
          this.permissions = initial;
      }
docs: Sets shared access permissions using the specified permissions string.
  
  @param value
  A <code>String</code> that represents the shared access permissions. The string must contain one or
  more of the following values. Note they must all be lowercase.
  <ul>
  <li><code>r</code>: Read access.</li>
  <li><code>c</code>: Create access.</li>
  <li><code>w</code>: Write access.</li>
  <li><code>d</code>: Delete access.</li>
  <li><code>l</code>: List access.</li>
  </ul>