code: protected void deletePrincipal() {
  
          try {
              String principalNameToCopyTo = m_principalSelect.getValue();
              I_CmsPrincipal principalTarget = null;
              if (!CmsStringUtil.isEmptyOrWhitespaceOnly(principalNameToCopyTo)) {
                  principalTarget = CmsPrincipal.readPrincipal(m_cms, principalNameToCopyTo);
              }
  
              for (CmsUUID id : m_groupIDs) {
                  m_cms.deleteGroup(id, principalTarget != null ? principalTarget.getId() : null);
              }
              for (CmsUUID id : m_userIDs) {
                  m_cms.deleteUser(id, principalTarget != null ? principalTarget.getId() : null);
              }
          } catch (CmsException e) {
              LOG.error("Unable to delete principal", e);
          }
      }
docs: Deletes the given user.<p>