小编use*_*812的帖子

我需要知道如何比较Prolog中两个列表的长度.这是我到目前为止:

sum(N1,N2) :-
    checklength(N1,N2).

checklength(N1,N2) :-
    L1 is length(N1,What),
    L2 is length(N2,What),
    Comp(L1,L2).

Comp(L1,L2) :-
    L1=:=L2.

我正在使用hibernate执行CRUD操作的项目.我有用户模型,我试图插入信息,但不断收到此错误

Hibernate: insert into APPUSER (dob, email, firstName, lastName, password) values (?, ?, ?, ?, ?)
Jun 21, 2016 2:17:07 AM org.hibernate.engine.jdbc.spi.SqlExceptionHelper logExceptions
WARN: SQL Error: 1400, SQLState: 23000
Jun 21, 2016 2:17:07 AM org.hibernate.engine.jdbc.spi.SqlExceptionHelper logExceptions
ERROR: ORA-01400: cannot insert NULL into ("MYAPP8785"."APPUSER"."ID")

用户模型看起来像

@Entity
@Table(name="APPUSER")
public class AppUser {


    @Id 
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id;

    @Email
    @Size(max = 50)
    private String email;

    @Column
    private String dob;

    @Column
    private String firstName;

    @Column
    private String lastName;

    @Column(name = "password", nullable …

我有一个Map和List它看起来像

int total = 0;
int incr = 10;
Map<String, Boolean> hashMap = new HashMap();
hashMap.put("A", true);
hashMap.put("B", false);
hashMap.put("C", true);

List<String> states = new ArrayList<>();
states.add("A");
states.add("B");
states.add("D");
states.add("E");
states.add("F");

每当我从列表中找到一个键时,Map我想用增量值递增总计;

states.stream()
            .filter(s -> hashMap.containsKey(s) && hashMap.get(s))
            .forEach((s) -> {total = total + incr;} );