No result defined for action com.zph.ssh.actions.CourseAction and result input

今天写ssh程序，遇到一个头疼的问题，提醒我No result defined for action com.zph.ssh.actions.CourseAction and result input 。。。奇了怪了，我哪里没对应？？
大家看代码：
course-list.jsp

<s:form action="course-save.action">
        <s:textfield name="xxx" label="xxx"></s:textfield>
        <s:select list="#request.courses" listKey="id" listValue="name"
            label="课程列表" name="course"></s:select>
        <s:submit></s:submit>
    </s:form>

Struts.xml

        <action name="course-*" class="courseAction" method="{1}">
            <result name="list">/WEB-INF/course/course-list.jsp</result>
            <result name="save">success.jsp</result>
        </action>

CourseAction.xml

    public String save() {
        // courseChoose.setCourse(course);
        System.out.println("111111111111111");
        /*
         * courseChoose.setDate(new Date()); teacher =
         * teacherService.getByTeacherName(LoginAction.username);
         * courseChoose.setTeacher(teacher);
         */
        System.out.println(courseChoose + "courseChoose");
        // courseService.saveOrUpdate(courseChoose);
        return "save";
    }

..struts就这么折磨了我一整天。后来查了不少资料，发现问题不是出在action和struts.xml,而是出在了jsp页面上。

  <s:select list="#request.courses" listKey="id" listValue="name"
            label="课程列表" name="course"></s:select>

这几句代码出了问题，<s:select list="#request.courses" listKey="id" listValue="name"
label="课程列表" name="course.id"></s:select>
,把course改成course.id就好了。