@Override
	protected AuthorizationInfo doGetAuthorizationInfo(PrincipalCollection principalCollection) {
		// 获取登录用户，就是这个地方出现的类型转换错误
		User sysuser = (User)principalCollection.getPrimaryPrincipal();		
		// 查询用户详情
		User user = userService.selectByUserName(sysuser.getUserName());
		// 添加角色和权限
		SimpleAuthorizationInfo simpleAuthorizationInfo = new SimpleAuthorizationInfo();
		List<String> roleNameList = new ArrayList<>();
		List<String> permissionNameList = new ArrayList<>();
		for (Role role : user.getRoles()) {
			roleNameList.add(role.getRoleName());
			for (Permission permission : role.getPermissions()) {
				permissionNameList.add(role.getRoleName()+":"+permission.getPermissionName());
			}
		}
		// 添加角色
		simpleAuthorizationInfo.addRoles(roleNameList);
		// 添加权限
		simpleAuthorizationInfo.addStringPermissions(permissionNameList);
		return simpleAuthorizationInfo;
	}

? ? ? ?出现这种情况的原因是 类加载器（?ClassLoader )?不同导致的?类型转换错误，因为项目采用的是 spring-boot-devtools 热部署的方式，项目启动时加载项目中的类使用的加载器都是 org.springframework.boot.devtools.restart.classloader.RestartClassLoader ，而从 shiro session 中取出来的对象（从 redis 中取出经过反序列化）的类加载器都是sun.misc.Launcher.AppClassLoader 。两者不同导致的出现这种结果。

解决方式一：

? ? ? ?不在项目中使用热部署，即注释掉热部署的依赖即可，如下所示：

        <!--热部署依赖 
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-devtools</artifactId>
			<scope>runtime</scope>
		</dependency>
        -->

    @Override
	protected AuthorizationInfo doGetAuthorizationInfo(PrincipalCollection principalCollection) {		
		User sysuser;
		Object object = principalCollection.getPrimaryPrincipal();
		if (object instanceof User) {
			sysuser = (User) object;
		} else {
			sysuser = JSON.parseObject(JSON.toJSON(object).toString(), User.class);
		}
		// 查询用户名称
		User user = userService.selectByUserName(sysuser.getUserName());
		// 添加角色和权限
		SimpleAuthorizationInfo simpleAuthorizationInfo = new SimpleAuthorizationInfo();
		List<String> roleNameList = new ArrayList<>();
		List<String> permissionNameList = new ArrayList<>();
		for (Role role : user.getRoles()) {
			roleNameList.add(role.getRoleName());
			for (Permission permission : role.getPermissions()) {
				permissionNameList.add(role.getRoleName()+":"+permission.getPermissionName());
			}
		}
		// 添加角色
		simpleAuthorizationInfo.addRoles(roleNameList);
		// 添加权限
		simpleAuthorizationInfo.addStringPermissions(permissionNameList);
		return simpleAuthorizationInfo;
	}