springboot（17）- 整合web開發（9）- 整合web基礎組件

1 整合 web 基礎組件

@WebServlet(urlPatterns = "/myservlet")
public class MyServlet extends HttpServlet {

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println("myServlet");
    }
}

@WebFilter(urlPatterns = "/*")
public class MyFilter implements Filter {

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        System.out.println("MyFilter");
        chain.doFilter(request, response);
    }
}

@WebListener
public class MyRequestListener implements ServletRequestListener {

    @Override
    public void requestDestroyed(ServletRequestEvent sre) {
        System.out.println("requestDestroyed");
    }

    @Override
    public void requestInitialized(ServletRequestEvent sre) {
        System.out.println(" requestInitialized");
    }
}

• 啓動類
  
  

2 路徑映射

<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>

2.1 傳統案例

@Controller
public class HelloController {

    @GetMapping("/hello")
    public String hello(){
        return "hello";
    }
}

2.2 使用配置類

package com.tzb;

import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration
public class WebMvcConfig implements WebMvcConfigurer {

    @Override
    public void addViewControllers(ViewControllerRegistry registry) {
        registry.addViewController("/tzb").setViewName("hello");
    }
}

3 使用類型轉換器

@RestController
public class UserController {

    @GetMapping("/hello")
    public void hello(Date birth){
        System.out.println(birth);
    }

}

---

• 日期轉換類

package com.tzb;

import org.springframework.core.convert.converter.Converter;
import org.springframework.stereotype.Component;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;

@Component
public class DateConverter implements Converter<String,Date> {

    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

    @Override
    public Date convert(String s) {
        if(s != null && !"".equals(s)){
            try {
                return sdf.parse(s);
            } catch (ParseException e) {
                e.printStackTrace();
            }
        }
        return null;
    }
}