Error:
***************************
APPLICATION FAILED TO START
***************************

Description:

The bean 'dataSource', defined in BeanDefinition defined in class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Hikari.class], could not be registered. A bean with that name has already been defined in class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Hikari.class] and overriding is disabled.

Action:

Consider renaming one of the beans or enabling overriding by setting spring.main.allow-bean-definition-overriding=true

spring:
  datasource:
#    type: com.zaxxer.hikari.HikariDataSource
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/test
    username: root
    password: root

  jpa:
    hibernate:
      ddl-auto: update
    show-sql: true

security:
  oauth2:
    resource:
      filter-order: 3

@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
@Entity
public class User {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private long id;

    @Column
    private String username;

    @Column(length = 60)
    @JsonIgnore
    private String password;

    @Column
    private long salary;

    @Column
    private int age;
}

@Configuration
@EnableWebSecurity
@EnableGlobalMethodSecurity(prePostEnabled = true)
public class SecurityConfig extends WebSecurityConfigurerAdapter {

    @Resource(name = "userService")
    private UserDetailsService userDetailsService;

    @Override
    @Bean
    public AuthenticationManager authenticationManagerBean() throws Exception {
        return super.authenticationManagerBean();
    }

    @Autowired
    public void globalUserDetails(AuthenticationManagerBuilder auth) throws Exception {
        auth.userDetailsService(userDetailsService).passwordEncoder(encoder());
    }

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.csrf().disable().anonymous().disable().authorizeRequests().antMatchers("/api-docs/**").permitAll();
    }

    @Bean
    public TokenStore tokenStore() {
        return new InMemoryTokenStore();
    }

    @Bean
    public BCryptPasswordEncoder encoder() {
        return new BCryptPasswordEncoder();
    }

    @Bean
    public FilterRegistrationBean corsFilter() {
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        CorsConfiguration config = new CorsConfiguration();
        config.setAllowCredentials(true);
        config.addAllowedOrigin("*");
        config.addAllowedHeader("*");
        config.addAllowedMethod("*");
        source.registerCorsConfiguration("/**", config);

        FilterRegistrationBean bean = new FilterRegistrationBean(new CorsFilter(source));
        bean.setOrder(0);
        return bean;
    }
}

@Configuration
@EnableResourceServer
public class ResourceServerConfig extends ResourceServerConfigurerAdapter {

    private static final String RESOURCE_ID = "resource_id";

    @Override
    public void configure(ResourceServerSecurityConfigurer resources) {
        resources.resourceId(RESOURCE_ID).stateless(false);
    }

    @Override
    public void configure(HttpSecurity http) throws Exception {
        http.anonymous().disable()
            .authorizeRequests().antMatchers("/users/**").access("hasRole('ADMIN')")
            .and()
            .exceptionHandling().accessDeniedHandler(new OAuth2AccessDeniedHandler());
    }
}

@Configuration
@EnableAuthorizationServer
public class AuthorizationServerConfig extends AuthorizationServerConfigurerAdapter {

    static final String CLIEN_ID = "devglan-client";
    static final String CLIENT_SECRET = "devglan-secret";
    static final String GRANT_TYPE_PASSWORD = "password";
    static final String AUTHORIZATION_CODE = "authorization_code";
    static final String REFRESH_TOKEN = "refresh_token";
    static final String IMPLICIT = "implicit";
    static final String SCOPE_READ = "read";
    static final String SCOPE_WRITE = "write";
    static final String TRUST = "trust";
    static final int ACCESS_TOKEN_VALIDITY_SECONDS = 1 * 60 * 60;
    static final int FREFRESH_TOKEN_VALIDITY_SECONDS = 6 * 60 * 60;

    @Autowired
    private TokenStore tokenStore;

    @Autowired
    private AuthenticationManager authenticationManager;

    @Override
    public void configure(ClientDetailsServiceConfigurer configurer) throws Exception {

        configurer.inMemory().withClient(CLIEN_ID).secret(CLIENT_SECRET)
                .authorizedGrantTypes(GRANT_TYPE_PASSWORD, AUTHORIZATION_CODE, REFRESH_TOKEN, IMPLICIT)
                .scopes(SCOPE_READ, SCOPE_WRITE, TRUST)
                .accessTokenValiditySeconds(ACCESS_TOKEN_VALIDITY_SECONDS)
                .refreshTokenValiditySeconds(FREFRESH_TOKEN_VALIDITY_SECONDS);
    }

    @Override
    public void configure(AuthorizationServerEndpointsConfigurer endpoints) throws Exception {
        endpoints.tokenStore(tokenStore).authenticationManager(authenticationManager);
    }
}

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-jpa</artifactId>
    <exclusions>
        <exclusion>
            <groupId>com.zaxxer</groupId>
            <artifactId>HikariCP</artifactId>
        </exclusion>
    </exclusions>
</dependency>