content: /*
   * Copyright 2010-2025 Hyland Software, Inc. and its affiliates.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.activiti.core.common.spring.security;
  
  import static java.util.Collections.emptyList;
  
  import java.security.Principal;
  import java.util.Collection;
  import java.util.Optional;
  import org.springframework.lang.NonNull;
  import org.springframework.security.core.Authentication;
  import org.springframework.security.core.GrantedAuthority;
  
  public class SimpleGrantedAuthoritiesResolver implements GrantedAuthoritiesResolver {
  
      @Override
      public Collection<? extends GrantedAuthority> getAuthorities(@NonNull Principal principal) {
          return Optional.of(principal)
              .filter(this::isSupportedPrincipal)
              .map(this.getPrincipalClass()::cast)
              .map(this::getAuthorities)
              .orElseThrow(this::securityException);
      }
  
      protected SecurityException securityException() {
          return new SecurityException("Invalid principal authorities");
      }
  
      protected <T> Collection<? extends GrantedAuthority> getAuthorities(Authentication authentication) {
          return Optional.ofNullable(authentication.getAuthorities()).orElseGet(this::emptyAuthorities);
      }
  
      protected <T> Collection<T> emptyAuthorities() {
          return emptyList();
      }
  
      protected Boolean isSupportedPrincipal(Principal principal) {
          return getPrincipalClass().isInstance(principal);
      }
  
      protected <T> Class<? extends Authentication> getPrincipalClass() {
          return Authentication.class;
      }
  }
  