一：servlet
（1）启动类
@SpringBootApplication
@ServletComponentScan
public class Application {
public static void main(String[] args){
SpringApplication.run(Application.class, args);
}
}
启动类用@ServletComponentScan注解标注
（2）继承HttpServlet
@WebServlet(name = "webServlet", urlPatterns = "/webServlet", loadOnStartup = 2)
public class WebServletTest extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
System.out.println("########doGet###########");
System.out.println("WebServletTest.doGet");
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
System.out.println("########doPost###########");
System.out.println("WebServletTest.doPost");
}
}
（3）访问http://localhost:8080/webServlet 运行结果：
二：Filters
测试示例1
@WebFilter(urlPatterns = "/*",filterName="CharacterEncodeFilter",
initParams={
@WebInitParam(name="encoding",value="UTF-8"),
@WebInitParam(name = "forceEncoding", value = "true")
})
@Singleton
public class CharacterEncodingFilter implements Filter {
private String encoding = "UTF-8";
private boolean forceEncoding = true;
@Override
public void init(FilterConfig filterConfig) throws ServletException {
this.encoding = filterConfig.getInitParameter("encoding");
String force = filterConfig.getInitParameter("forceEncoding");
this.forceEncoding = (force == null) || Boolean.valueOf(force);
}
@Override
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
if (this.forceEncoding || servletRequest.getCharacterEncoding() == null) {
servletRequest.setCharacterEncoding(this.encoding);
servletResponse.setCharacterEncoding(this.encoding);
}
filterChain.doFilter(servletRequest, servletResponse);
}
@Override
public void destroy() {
}
}
测试示例2
@WebFilter(urlPatterns = "/*", filterName = "indexFilter")
public class IndexFilter implements Filter {
private final static Logger logger = LoggerFactory.getLogger(IndexFilter.class);
@Override
public void init(FilterConfig filterConfig) throws ServletException {
logger.info("init IndexFilter");
}
@Override
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
logger.info("IndexFilter.doFilter exec");
filterChain.doFilter(servletRequest,servletResponse);
}
@Override
public void destroy() {
}
}
三： listeners
示例
@WebListener
public class MyServletContextListener implements ServletContextListener {
@Override
public void contextInitialized(ServletContextEvent servletContextEvent) {
System.out.println("ServletContex初始化");
}
@Override
public void contextDestroyed(ServletContextEvent servletContextEvent) {
System.out.println("ServletContex销毁");
}
}
运行结果：
