Spring Filter

1.使用Java自己本身的Filter

@SpringBootApplication
@ServletComponentScan("test.annotation.filter")
public class SptringAnnotationFilterApplication {
    public static void main(String[] args) {
        SpringApplication.run(SptringAnnotationFilterApplication.class, args);
    }
}


@WebFilter(
    filterName="testFilter",
    urlPatterns={"/testRest"}
)
public class SpringAnnotationFilter implements Filter{
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain filterChain)
            throws IOException, ServletException {
        // do something

        filterChain.doFilter(request, response);
    }

    @Override
    public void destroy() {

    }
}

SptringAnnotationFilterApplication
1. 設定@ServletComponentScan(filter的package)

SpringAnnotationFilter
1. implements javax.servlet.Filter
2. 設定@WebFilter(urlPatterns是設定哪些url要filter)
3. 改寫doFilter

這樣filter就可以生效

註：
若有多個filter時，在這邊使用Spring的@Order是沒有用的
真的要使用order的話可以參考下面第二種作法or使用package name去控制filter順序

2.使用Spring的FilterRegistrationBean

@SpringBootApplication
public class SpringBeanConfigFilterApplication {
    public static void main(String[] args) {
        SpringApplication.run(SpringBeanConfigFilterApplication.class, args);
    }
}

@Configuration
public class FilterConfig {
    @Bean
    public FilterRegistrationBean<Filter> registFilter() {
        FilterRegistrationBean<Filter> registration = new FilterRegistrationBean<>();
        registration.setFilter(new SpringBeanConfigFilter());
        registration.addUrlPatterns("/testRest");
        registration.setOrder(2);
        registration.setName("testFilter");
        return registration;
    }

    @Bean
    public FilterRegistrationBean<Filter> registFilter2() {
        FilterRegistrationBean<Filter> registration = new FilterRegistrationBean<>();
        registration.setFilter(new SpringBeanConfigFilter2());
        registration.addUrlPatterns("/testRest");
        registration.setOrder(1);
        registration.setName("testFilter2");
        return registration;
    }
}

public class SpringBeanConfigFilter implements Filter{
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain filterChain)
            throws IOException, ServletException {
        // do something

        filterChain.doFilter(request, response);
    }

    @Override
    public void destroy() {

    }
}

public class SpringBeanConfigFilter2 implements Filter{
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain filterChain)
            throws IOException, ServletException {
        // do something

        filterChain.doFilter(request, response);
    }

    @Override
    public void destroy() {

    }
}

使用Spring bean的方式去做設定
註：此設定的方式可以設定filter order

完整程式可參考https://github.com/softmenlouis/springBoot-filter.git