# 一。通過配置文件
```
# application.yml
spring:
security:
user:
name: admin
password: admin
```
# 二。通過配置類
1. 創建一個SecurityConfig 類 繼承 WebSecurityConfigurerAdapter 并且 添加@Configuration 注解
2. 重寫 protected void configure(AuthenticationManagerBuilder auth) 方法
3. 把PasswordEncoder 的實現類加載到Bean中
```
package cn.maicaii.security.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
import org.springframework.security.crypto.password.PasswordEncoder;
@Configuration
public class SecurityConfig extends WebSecurityConfigurerAdapter {
@Override
protected void configure(AuthenticationManagerBuilder auth) throws Exception {
auth.
inMemoryAuthentication()
.withUser("admin")
.password(passwordEncoder().encode("123"))
.roles("admin");
}
@Bean
public PasswordEncoder passwordEncoder() {
return new BCryptPasswordEncoder();
}
}
```
# 三。通過實現類
1. 創建一個SecurityConfig 類 編寫使用哪個 UserDetailsService實現類
```
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
import org.springframework.security.crypto.password.PasswordEncoder;
@Configuration
public class SecurityConfig extends WebSecurityConfigurerAdapter {
@Autowired
private UserDetailsService userDetailsService;
@Override
protected void configure(AuthenticationManagerBuilder auth) throws Exception {
auth
.userDetailsService(userDetailsService)
.passwordEncoder(passwordEncoder());
}
@Bean
public PasswordEncoder passwordEncoder() {
return new BCryptPasswordEncoder();
}
}
```
2. 編寫 UserDetailsService實現類 實現 loadUserByUsername 返回User對象
```
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.core.GrantedAuthority;
import org.springframework.security.core.authority.AuthorityUtils;
import org.springframework.security.core.userdetails.User;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.core.userdetails.UsernameNotFoundException;
import org.springframework.security.crypto.password.PasswordEncoder;
import org.springframework.stereotype.Service;
import java.util.List;
@Service("userDetailsService")
public class UserDetailsServiceImpl implements UserDetailsService {
@Autowired
private PasswordEncoder passwordEncoder;
@Override
public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
// 權限
List<GrantedAuthority> role = AuthorityUtils.commaSeparatedStringToAuthorityList("role");
User user = new User(
"admin",
passwordEncoder.encode("123"),
role
);
return user;
}
}
```
