The extended for statement causes ClassCastException.

 ■ Test class
@ Controller    
public class test {

    @RequestMapping(value="/login", method=RequestMethod.GET)
    public String login(@RequestParam(value="name", required=false, defaultValue="World") String name, Model model) {


        RestTemplate restTemplate = new RestTemplate();
        @SuppressWarnings ("unchecked")
        List<Student>aiu=restTemplate.getForObject("http://localhost:9292/student?userId=00002", List.class);

        for (Student a:aiu) {
            System.out.println(a.getId());

        }
        return "login";
    }
}

■ Student Class
public class Student {
    private String id;
    private String name;
    private String score;
    public String getId() {
        return id;
    }
    public void setId(String id){
        this.id=id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name){
        this.name = name;
    }
    public String getScore() {
        return score;
    }
    public void setScore(String score){
        This.score=score;
    }
}

■ StudentController Class
@RestController
public class StudentController {

    @RequestMapping(value="/student", method=RequestMethod.GET)

    publicList<Student>get(@RequestParamStringuserId){

        List<Student>a=new ArrayList<Student>();

        Student aa = new Student();
        aa.setId("0001");
        aa.setName("Ando");
        aa.setScore("30");

        Student ab = new Student();
        ab.setId("0002");
        ab.setName("Tanaka");
        ab.setScore("48");

        a.add(aa);
        a.add(ab);

        return a;
    }
}