springsecurity 权限校验使用代码举例

好的，下面给出一个基于Spring Security的权限校验的示例代码：

1. 定义User对象

public class User implements UserDetails {
    private Long id;
    private String username;
    private String password;
    private List<Role> roles;

    // getters and setters

    @Override
    public Collection<? extends GrantedAuthority> getAuthorities() {
        List<GrantedAuthority> authorities = new ArrayList<>();
        for (Role role : roles) {
            authorities.add(new SimpleGrantedAuthority(role.getName()));
        }
        return authorities;
    }

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

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

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

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

2. 定义Role对象

public class Role {
    private Long id;
    private String name;

    // getters and setters
}

3. 实现UserDetailsService接口

@Service
public class UserDetailsServiceImpl implements UserDetailsService {
    @Autowired
    private UserRepository userRepository;

    @Override
    public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
        User user = userRepository.findByUsername(username);
        if (user == null) {
            throw new UsernameNotFoundException("用户不存在");
        }
        return user;
    }
}

4. 配置Spring Security

@Configuration
@EnableWebSecurity
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {
    @Autowired
    private UserDetailsService userDetailsService;

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.authorizeRequests()
                .antMatchers("/admin/**").hasRole("ADMIN")
                .antMatchers("/user/**").hasRole("USER")
                .anyRequest().authenticated()
                .and()
                .formLogin()
                .loginPage("/login")
                .defaultSuccessUrl("/")
                .permitAll()
                .and()
                .logout()
                .permitAll();
    }

    @Override
    protected void configure(AuthenticationManagerBuilder auth) throws Exception {
        auth.userDetailsService(userDetailsService);
    }

    @Bean
    public PasswordEncoder passwordEncoder() {
        return new BCryptPasswordEncoder();
    }
}

5. 在Controller中使用注解进行权限校验

@RestController
@RequestMapping("/admin")
@PreAuthorize("hasRole('ADMIN')")
public class AdminController {
    // ...
}

@RestController
@RequestMapping("/user")
@PreAuthorize("hasAnyRole('USER', 'ADMIN')")
public class UserController {
    // ...
}

以上代码示例中，我们首先定义了一个User对象和一个Role对象，User对象实现了UserDetails接口，并在getAuthorities方法中返回该用户所拥有的权限列表。然后我们实现了UserDetailsService接口，在loadUserByUsername方法中根据用户名从数据库中查询用户信息。接着我们配置了Spring Security，使用HttpSecurity对象进行权限校验的配置，使用AuthenticationManagerBuilder对象配置UserDetailsService，并使用PasswordEncoder对象进行密码加密。最后，在Controller中使用@PreAuthorize注解进行权限校验。