001/* 002 * Copyright 2002-2013 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * https://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.messaging.simp.annotation.support; 018 019import java.security.Principal; 020 021import org.springframework.core.MethodParameter; 022import org.springframework.messaging.Message; 023import org.springframework.messaging.handler.invocation.HandlerMethodArgumentResolver; 024import org.springframework.messaging.simp.SimpMessageHeaderAccessor; 025 026/** 027 * @author Rossen Stoyanchev 028 * @since 4.0 029 */ 030public class PrincipalMethodArgumentResolver implements HandlerMethodArgumentResolver { 031 032 @Override 033 public boolean supportsParameter(MethodParameter parameter) { 034 Class<?> paramType = parameter.getParameterType(); 035 return Principal.class.isAssignableFrom(paramType); 036 } 037 038 @Override 039 public Object resolveArgument(MethodParameter parameter, Message<?> message) throws Exception { 040 Principal user = SimpMessageHeaderAccessor.getUser(message.getHeaders()); 041 if (user == null) { 042 throw new MissingSessionUserException(message); 043 } 044 return user; 045 } 046 047}