Java 转换集合<；对象>；列出<；字符串>；

我无法从

用户

对象中的

角色集合

中获取作为

字符串

列表的用户角色。 我想将用户角色设置为

List

以在

loadUserByUsername

方法上的

userserviceimentation

中实现它，在该方法中，我将角色名称作为列表传递给

socialUserDetailsSimplementation

类，以使社交登录可用。我会感激你的解决方案

用户模型：

@Entity
@Table(uniqueConstraints = @UniqueConstraint(columnNames = "email"))
public class User {

    public static final String ROLE_USER = "ROLE_USER";
    public static final String ROLE_ADMIN = "ROLE_ADMIN";

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name ="user_id", nullable = false)
    private Long userId;

    private String firstName;
    private String lastName;
    private String email;
    private String password;
    private String userName;

    @ManyToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
    @JoinTable(
            name = "users_roles",
            joinColumns = @JoinColumn(
                    name = "user_id", referencedColumnName = "user_id"),
            inverseJoinColumns = @JoinColumn(
                    name = "role_id", referencedColumnName = "id"))
    private Collection<Role> roles;

    @Column(name = "enabled")
    private boolean enabled;


    public User() {
        super();
        this.enabled=false;

    }

    public User(String firstName, String lastName, String email, String password) {
        this.firstName = firstName;
        this.lastName = lastName;
        this.email = email;
        this.password = password;
    }

    public User(String firstName, String lastName, String email, String password, Collection<Role> roles) {
        this.firstName = firstName;
        this.lastName = lastName;
        this.email = email;
        this.password = password;
        this.roles = roles;
    }

    public User(String firstName, String lastName, String email, String password, String userName, Collection<Role> roles) {
        this.firstName = firstName;
        this.lastName = lastName;
        this.email = email;
        this.password = password;
        this.userName = userName;
        this.roles = roles;
    }

    public Long getUserId() {
        return userId;
    }

    public void setUserId(Long userId) {
        this.userId = userId;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public boolean isEnabled() {
        return enabled;
    }

    public void setEnabled(boolean enabled) {
        this.enabled = enabled;
    }

    public Collection<Role> getRoles() {
        return roles;
    }

    public void setRoles(Collection<Role> roles) {
        this.roles = roles;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }


}

@Service
public class UserServiceImpl implements UserService {

    @Autowired
    private UserRepository userRepository;




    @Override
    public UserDetails loadUserByUsername(String userName) throws UsernameNotFoundException {
        User user = userRepository.findByUserName(userName);
        if (user == null) {
            throw new UsernameNotFoundException("Invalid username or password.");
        }


       List<String> roleNames =  (Collectors.toList(user.getRoles()));



        List<GrantedAuthority> grantList = new ArrayList<GrantedAuthority>();
        if (roleNames != null) {
            for (String role : roleNames) {
                GrantedAuthority authority = new SimpleGrantedAuthority(role);
                grantList.add(authority);
            }
        }


        SocialUserDetailsImpl userDetails = new SocialUserDetailsImpl(user,  roleNames);
                return userDetails;
    }

public class SocialUserDetailsImpl implements SocialUserDetails {

private static final long serialVersionUID = 1L;
private List<GrantedAuthority> list = new ArrayList<GrantedAuthority>();
private User user;

public SocialUserDetailsImpl(User user, List<String> roleNames) {
    this.user = user;

    for (String roleName : roleNames) {

        GrantedAuthority grant = new SimpleGrantedAuthority(roleName);
        this.list.add(grant);
    }
}

@Override
public String getUserId() {
    return this.user.getUserId() + "";
}

@Override
public String getUsername() {
    return user.getUserName();
}

@Override
public Collection<? extends GrantedAuthority> getAuthorities() {
    return list;
}

@Override
public String getPassword() {
    return user.getPassword();
}

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

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

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

@Override
public boolean isEnabled() {
    return this.user.isEnabled();
}

}

@实体
@表（uniqueConstraints=@UniqueConstraint（columnNames=“email”））
公共类用户{
公共静态最终字符串ROLE\u USER=“ROLE\u USER”；
公共静态最终字符串ROLE\u ADMIN=“ROLE\u ADMIN”；
@身份证
@GeneratedValue（策略=GenerationType.AUTO）
@列（name=“user\u id”，null=false）
私有长用户ID；
私有字符串名；
私有字符串lastName；
私人字符串电子邮件；
私有字符串密码；
私有字符串用户名；
@ManyToMany（fetch=FetchType.EAGER，cascade=CascadeType.ALL）
@可接合(
name=“用户\角色”，
joinColumns=@JoinColumn(
name=“user\u id”，referencedColumnName=“user\u id”），
inverseJoinColumns=@JoinColumn(
name=“role\u id”，referencedColumnName=“id”））
私人收藏角色；
@列（name=“enabled”）
启用私有布尔值；
公共用户（）{
超级（）；
此.enabled=false；
}
公共用户（字符串名、字符串名、字符串电子邮件、字符串密码）{
this.firstName=firstName；
this.lastName=lastName；
this.email=电子邮件；
this.password=密码；
}
公共用户（字符串名、字符串名、字符串电子邮件、字符串密码、集合角色）{
this.firstName=firstName；
this.lastName=lastName；
this.email=电子邮件；
this.password=密码；
this.roles=角色；
}
公共用户（字符串名、字符串名、字符串电子邮件、字符串密码、字符串用户名、集合角色）{
this.firstName=firstName；
this.lastName=lastName；
this.email=电子邮件；
this.password=密码；
this.userName=用户名；
this.roles=角色；
}
公共长getUserId（）{
返回用户标识；
}
public void setUserId（长userId）{
this.userId=userId；
}
公共字符串getFirstName（）{
返回名字；
}
public void setFirstName（字符串firstName）{
this.firstName=firstName；
}
公共字符串getLastName（）{
返回姓氏；
}
public void setLastName（字符串lastName）{
this.lastName=lastName；
}
公共字符串getEmail（）{
回复邮件；
}
公用电子邮件（字符串电子邮件）{
this.email=电子邮件；
}
公共字符串getPassword（）{
返回密码；
}
public void setPassword（字符串密码）{
this.password=密码；
}
公共布尔值isEnabled（）{
返回启用；
}
已启用公共void集（已启用布尔值）{
this.enabled=已启用；
}
公共集合getRoles（）{
返回角色；
}
公共void集合角色（集合角色）{
this.roles=角色；
}
公共字符串getUserName（）{
返回用户名；
}
public void setUserName（字符串用户名）{
this.userName=用户名；
}
}

UserServiceImpl：

@Entity
@Table(uniqueConstraints = @UniqueConstraint(columnNames = "email"))
public class User {

    public static final String ROLE_USER = "ROLE_USER";
    public static final String ROLE_ADMIN = "ROLE_ADMIN";

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name ="user_id", nullable = false)
    private Long userId;

    private String firstName;
    private String lastName;
    private String email;
    private String password;
    private String userName;

    @ManyToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
    @JoinTable(
            name = "users_roles",
            joinColumns = @JoinColumn(
                    name = "user_id", referencedColumnName = "user_id"),
            inverseJoinColumns = @JoinColumn(
                    name = "role_id", referencedColumnName = "id"))
    private Collection<Role> roles;

    @Column(name = "enabled")
    private boolean enabled;


    public User() {
        super();
        this.enabled=false;

    }

    public User(String firstName, String lastName, String email, String password) {
        this.firstName = firstName;
        this.lastName = lastName;
        this.email = email;
        this.password = password;
    }

    public User(String firstName, String lastName, String email, String password, Collection<Role> roles) {
        this.firstName = firstName;
        this.lastName = lastName;
        this.email = email;
        this.password = password;
        this.roles = roles;
    }

    public User(String firstName, String lastName, String email, String password, String userName, Collection<Role> roles) {
        this.firstName = firstName;
        this.lastName = lastName;
        this.email = email;
        this.password = password;
        this.userName = userName;
        this.roles = roles;
    }

    public Long getUserId() {
        return userId;
    }

    public void setUserId(Long userId) {
        this.userId = userId;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public boolean isEnabled() {
        return enabled;
    }

    public void setEnabled(boolean enabled) {
        this.enabled = enabled;
    }

    public Collection<Role> getRoles() {
        return roles;
    }

    public void setRoles(Collection<Role> roles) {
        this.roles = roles;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }


}

@Service
public class UserServiceImpl implements UserService {

    @Autowired
    private UserRepository userRepository;




    @Override
    public UserDetails loadUserByUsername(String userName) throws UsernameNotFoundException {
        User user = userRepository.findByUserName(userName);
        if (user == null) {
            throw new UsernameNotFoundException("Invalid username or password.");
        }


       List<String> roleNames =  (Collectors.toList(user.getRoles()));



        List<GrantedAuthority> grantList = new ArrayList<GrantedAuthority>();
        if (roleNames != null) {
            for (String role : roleNames) {
                GrantedAuthority authority = new SimpleGrantedAuthority(role);
                grantList.add(authority);
            }
        }


        SocialUserDetailsImpl userDetails = new SocialUserDetailsImpl(user,  roleNames);
                return userDetails;
    }

public class SocialUserDetailsImpl implements SocialUserDetails {

private static final long serialVersionUID = 1L;
private List<GrantedAuthority> list = new ArrayList<GrantedAuthority>();
private User user;

public SocialUserDetailsImpl(User user, List<String> roleNames) {
    this.user = user;

    for (String roleName : roleNames) {

        GrantedAuthority grant = new SimpleGrantedAuthority(roleName);
        this.list.add(grant);
    }
}

@Override
public String getUserId() {
    return this.user.getUserId() + "";
}

@Override
public String getUsername() {
    return user.getUserName();
}

@Override
public Collection<? extends GrantedAuthority> getAuthorities() {
    return list;
}

@Override
public String getPassword() {
    return user.getPassword();
}

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

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

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

@Override
public boolean isEnabled() {
    return this.user.isEnabled();
}

}

@服务
公共类UserServiceImpl实现UserService{
@自动连线
私有用户存储库用户存储库；
@凌驾
public UserDetails loadUserByUsername（字符串用户名）引发UsernameNotFoundException{
User=userRepository.findByUserName（用户名）；
if（user==null）{
抛出新用户名NotFoundException（“无效用户名或密码”）；
}
List roleNames=（Collectors.toList（user.getRoles（））；
List grantList=new ArrayList（）；
if（角色名称！=null）{
for（字符串角色：角色名称）{
授权机构=新的SimpleGrantedAuthority（角色）；
增列（授权）；
}
}
SocialUserDetailsImpl userDetails=新的SocialUserDetailsImpl（用户，角色名称）；
返回用户详细信息；
}

SocialUserDetailsImpl：

@Entity
@Table(uniqueConstraints = @UniqueConstraint(columnNames = "email"))
public class User {

    public static final String ROLE_USER = "ROLE_USER";
    public static final String ROLE_ADMIN = "ROLE_ADMIN";

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name ="user_id", nullable = false)
    private Long userId;

    private String firstName;
    private String lastName;
    private String email;
    private String password;
    private String userName;

    @ManyToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
    @JoinTable(
            name = "users_roles",
            joinColumns = @JoinColumn(
                    name = "user_id", referencedColumnName = "user_id"),
            inverseJoinColumns = @JoinColumn(
                    name = "role_id", referencedColumnName = "id"))
    private Collection<Role> roles;

    @Column(name = "enabled")
    private boolean enabled;


    public User() {
        super();
        this.enabled=false;

    }

    public User(String firstName, String lastName, String email, String password) {
        this.firstName = firstName;
        this.lastName = lastName;
        this.email = email;
        this.password = password;
    }

    public User(String firstName, String lastName, String email, String password, Collection<Role> roles) {
        this.firstName = firstName;
        this.lastName = lastName;
        this.email = email;
        this.password = password;
        this.roles = roles;
    }

    public User(String firstName, String lastName, String email, String password, String userName, Collection<Role> roles) {
        this.firstName = firstName;
        this.lastName = lastName;
        this.email = email;
        this.password = password;
        this.userName = userName;
        this.roles = roles;
    }

    public Long getUserId() {
        return userId;
    }

    public void setUserId(Long userId) {
        this.userId = userId;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public boolean isEnabled() {
        return enabled;
    }

    public void setEnabled(boolean enabled) {
        this.enabled = enabled;
    }

    public Collection<Role> getRoles() {
        return roles;
    }

    public void setRoles(Collection<Role> roles) {
        this.roles = roles;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }


}

@Service
public class UserServiceImpl implements UserService {

    @Autowired
    private UserRepository userRepository;




    @Override
    public UserDetails loadUserByUsername(String userName) throws UsernameNotFoundException {
        User user = userRepository.findByUserName(userName);
        if (user == null) {
            throw new UsernameNotFoundException("Invalid username or password.");
        }


       List<String> roleNames =  (Collectors.toList(user.getRoles()));



        List<GrantedAuthority> grantList = new ArrayList<GrantedAuthority>();
        if (roleNames != null) {
            for (String role : roleNames) {
                GrantedAuthority authority = new SimpleGrantedAuthority(role);
                grantList.add(authority);
            }
        }


        SocialUserDetailsImpl userDetails = new SocialUserDetailsImpl(user,  roleNames);
                return userDetails;
    }

public class SocialUserDetailsImpl implements SocialUserDetails {

private static final long serialVersionUID = 1L;
private List<GrantedAuthority> list = new ArrayList<GrantedAuthority>();
private User user;

public SocialUserDetailsImpl(User user, List<String> roleNames) {
    this.user = user;

    for (String roleName : roleNames) {

        GrantedAuthority grant = new SimpleGrantedAuthority(roleName);
        this.list.add(grant);
    }
}

@Override
public String getUserId() {
    return this.user.getUserId() + "";
}

@Override
public String getUsername() {
    return user.getUserName();
}

@Override
public Collection<? extends GrantedAuthority> getAuthorities() {
    return list;
}

@Override
public String getPassword() {
    return user.getPassword();
}

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

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

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

@Override
public boolean isEnabled() {
    return this.user.isEnabled();
}

}

公共类SocialUserDetailsImpl实现SocialUserDetails{
私有静态最终长serialVersionUID=1L；
私有列表=新的ArrayList（）；
私人用户；
public SocialUserDetailsImpl（用户、列表角色名称）{
this.user=用户；
用于（字符串roleName:roleName）{
授权授予=新的SimpleGrantedAuthority（roleName）；
本.列表.添加（授权）；
}
}
@凌驾
公共字符串getUserId（）{
返回此.user.getUserId（）+“”；
}
@凌驾
公共字符串getUsername（）{
返回user.getUserName（）；
}
@凌驾
本部分公共收藏

List<String> roleNames =  (Collectors.toList(user.getRoles()));

List roleNames=（Collectors.toList（user.getRoles（））；

您的角色名称包含user.getRoles（）.toString（）的列表，而不是预期的角色名称

试一试

List roleNames=user.getRoles（）.stream（）
.map（角色：：getName）
.collect（Collectors.toList（））；

另外，在“角色用户”和“角色管理”字段中添加临时用户。
执行类似操作

List<Object> roleNames =  (Collectors.toList(user.getRoles()));
List<String> roleNamesString= new List<string> ();

for(Object a: roleNames){
   roleNameString.add(String.valueOf(a));
}

List roleNames=（Collectors.toList（user.getRoles（））；
List roleNamesString=新列表（）；
用于（对象a：角色名称）{
添加（String.valueOf（a））；
}

根据模型的复杂性，您可能需要重写Role类的toString方法。
基本上，您不需要将角色转换为
列表
，您可以通过

user.getRoles().stream()
    .map(role -> new SimpleGrantedAuthority(role.getRoleName()))
    .collect(Collectors.toList());

如果您确实需要
列表
，那么您可以这样做

user.getRoles().stream()
    .map(Role::getRoleName)
    .collect(Collectors.toList());

Sooo问题是什么