To prevent XSS attacks in our form transactions:

1. Let's create a new security model that enables header filtering or sanitation, which is inherent to the Spring Security 4.2.2 framework:

@Configuration 
@EnableWebSecurity 
public class AppSecurityModelI extends  
    WebSecurityConfigurerAdapter{ 
   
  @Override 
  protected void configure(AuthenticationManagerBuilder auth) throws Exception { 
          // refer to sources     
  } 
    
  @Override 
  protected void configure(HttpSecurity http) throws Exception { 
     
      // refer to sources 
                   
         http.csrf().disable(); 
 
         http.headers().defaultsDisabled().cacheControl() 
          .and().headers().httpStrictTransportSecurity() 
          .and().contentTypeOptions().disable() 
          .frameOptions().deny()          
          .and().addHeaderWriter( 
            new StaticHeadersWriter( 
             "X-Content-Security-Policy", 
             "default-src 'auth'")); 
  } 
   
 @Override 
 public void configure(WebSecurity web) throws Exception { 
        // refer to sources 
 } 
} 

2. Save all files. clean, compile, and deploy the ch04 project.