Annotations: methods versus variables

Question

I was always sure (I don’t know why) that it’s better to add annotations to the variables, but when viewing the Hibernate document http://docs.jboss.org/hibernate/stable/annotations/reference/en/html_single/#entity-hibspec-collection I noticed that they tend to comment on methods. Therefore, I have to put my annotations before the methods, for example:

@Entity
public class Flight implements Serializable {
private long id;

@Id @GeneratedValue
public long getId() { return id; }

public void setId(long id) { this.id = id; }
}  

Or better to do it like this:

@Entity
public class Flight implements Serializable {
@Id @GeneratedValue
private long id;

public long getId() { return id; }

public void setId(long id) { this.id = id; }
}  

Or maybe there is no difference?

Answer 1

As Peter points out, you need to choose one style and stick to it, as the style adopted for annotation @Idwill be used for everything.

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Answer 2

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Answer 3

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@Column(...)
private String email;

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public String getHost() { ... split email and return the part after @ ... }
public void setHost(String host) { ... change the part after the @... }

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Answer 6

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@Entity
class User implements UserDetails {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;
    @OneToMany
    private List<UserRole> roles;

    //....Setters and Getters..........
    @Override
    public Collection<? extends GrantedAuthority> getAuthorities() {
        return null;
    }

    @Override
    public boolean isAccountNonExpired() {
        return false;
    }

    @Override
    public boolean isAccountNonLocked() {
        return false;
    }

    @Override
    public boolean isCredentialsNonExpired() {
        return false;
    }

    @Override
    public boolean isEnabled() {
        return false;
    }

If you put all annotations in the getters function, without displaying @OneToManyor @ManyToMany... it will work, but if you need to use this relationship, then Hibernate will break. I think Hibernate is already using annotation on top of the variable, so it doesn’t like annotating the top of functions for a consistent reason.

Thus, stick to what is common to the structure, you will not break your codes later.