使用注解替换Spring配置文件&SpringMVC的配置文件
创建初始化类，替换web.xml
-
在
Servlet3.0环境中，Web容器(Tomcat)会在类路径中查找实现javax.servlet.ServletContainerInitializer接口的类，如果找到的话就用它来配置Servlet容器。 -
Spring提供了这个接口的实现，名为
SpringServletContainerInitializer，这个类反过来又会查找实现WebApplicationInitializer的类并将配置的任务交给它们来完成。 -
Spring3.2引入了一个便利的WebApplicationInitializer基础实现，名为AbstractAnnotationConfigDispatcherServletInitializer，当我们的类扩展了AbstractAnnotationConfigDispatcherServletInitializer并将其部署到Servlet3.0容器的时候，容器会自动发现它，并用它来配置Servlet上下文。
/**
* @Author: lisong
* @CreateTime: 2024-01-31 17:36 星期三
* @Description: 当前类替换web.xml配置文件
*/
public class WebInit extends AbstractAnnotationConfigDispatcherServletInitializer {
//设置spring配置类，替代spring.xml配置文件
@Override
protected Class<?>[] getRootConfigClasses() {
return new Class[]{SpringConfig.class};
}
//设置springmvc配置类，替代springmvc.xml配置文件
@Override
protected Class<?>[] getServletConfigClasses() {
return new Class[]{SpringMVCConfig.class};
}
//设置SpringMVC的前端控制器DispatcherServlet的url-patten
@Override
protected String[] getServletMappings() {
return new String[]{"/"};
}
//设置当前工程的过滤器
@Override
protected Filter[] getServletFilters() {
//创建字符编码过滤器对象
CharacterEncodingFilter characterEncodingFilter = new CharacterEncodingFilter();
//设置字符编码
characterEncodingFilter.setEncoding("UTF-8");
//设置请求和响应的编码
characterEncodingFilter.setForceEncoding(true);
//创建rest风格请求方式的过滤器对象
HiddenHttpMethodFilter hiddenHttpMethodFilter = new HiddenHttpMethodFilter();
return new Filter[]{characterEncodingFilter,hiddenHttpMethodFilter};
}
}
创建Sping配置类，替换Spring的配置文件
@Configurable
@PropertySource("classpath:jdbc.properties")
public class SpringConfig {
//声明成员属性
@Value("${jdbc.driver}") //将jdbc.properties中的信息初始化到属性中
private String driver;
@Value("${jdbc.url}")
private String url;
@Value("${jdbc.username}")
private String username;
@Value("${jdbc.password}")
private String password;
//配置数据源
@Bean
public DruidDataSource dataSource() {
DruidDataSource dataSource = new DruidDataSource();
dataSource.setDriverClassName(driver);
dataSource.setUrl(url);
dataSource.setUsername(username);
dataSource.setPassword(password);
return dataSource;
}
//配置jdbc模板，将数据源注入到模板中
@Bean
public JdbcTemplate jdbcTemplate(DruidDataSource dataSource) {
JdbcTemplate jdbcTemplate = new JdbcTemplate();
jdbcTemplate.setDataSource(dataSource);
return jdbcTemplate;
}
}
jdbc.properties
jdbc.driver=com.mysql.cj.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/dbtest1
jdbc.username=root
jdbc.password=123456
创建SpringMVC配置类，替换SpringMVC配置文件
@Configurable //标识为配置类
@ComponentScan(basePackages = {"com.evan"})
@EnableWebMvc //开启mvc注解
public class WebConfig implements WebMvcConfigurer {
//配置Spring视图模板解析器的相关策略
@Bean
public ITemplateResolver templateResolver() {
//获取当前Web应用的上下文，即Web容器
WebApplicationContext webApplicationContext = ContextLoader.getCurrentWebApplicationContext();
//创建ServletContext对象,注入当前Web应用的上下文
ServletContextTemplateResolver templateResolver =
new ServletContextTemplateResolver(webApplicationContext.getServletContext());
//创建spring视图模板解析器对象
//SpringResourceTemplateResolver templateResolver = new SpringResourceTemplateResolver();
//设置视图字符集
templateResolver.setCharacterEncoding("UTF-8");
//设置视图优先级
templateResolver.setOrder(1);
//设置视图模式
templateResolver.setTemplateMode("HTML5");
//设置视图前缀
templateResolver.setPrefix("/WEB-INF/views/");
//设置视图后缀
templateResolver.setSuffix(".html");
return templateResolver;
}
//生成Spring的模板引擎，并为模板引擎注入模板解析器
@Bean
public TemplateEngine templateEngine(ITemplateResolver iTemplateResolver) {
SpringTemplateEngine templateEngine = new SpringTemplateEngine();
templateEngine.setTemplateResolver(iTemplateResolver);
return templateEngine;
}
//生成Thymeleaf视图解析器，并为视图解析器注入spring的模板引擎
@Bean
public ViewResolver thymeleafViewResolver(SpringTemplateEngine templateEngine) {
ThymeleafViewResolver thymeleafViewResolver = new ThymeleafViewResolver();
thymeleafViewResolver.setCharacterEncoding("UTF-8");
thymeleafViewResolver.setOrder(1);
thymeleafViewResolver.setTemplateEngine(templateEngine);
return thymeleafViewResolver;
}
//配置文件上传解析器
@Bean
public CommonsMultipartResolver multipartResolver() {
return new CommonsMultipartResolver();
}
//配置拦截器
@Override
public void addInterceptors(InterceptorRegistry registry) {
//创建自定义拦截器实现类对象
FirstInterceptor firstInterceptor = new FirstInterceptor();
//配置拦截所有请求路径,排除/hello请求
registry.addInterceptor(firstInterceptor).addPathPatterns("/**")
.excludePathPatterns("/hello");
}
//配置视图控制器
@Override
public void addViewControllers(ViewControllerRegistry registry) {
//设置视图控制器策略
registry.addViewController("/").setStatusCode(HttpStatus.OK).setViewName("index");
}
//配置默认的servlet处理静态资源
@Override
public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
//开启默认的servlet静态资源处理
configurer.enable();
}
//配置异常处理器
@Override
public void configureHandlerExceptionResolvers(List<HandlerExceptionResolver> resolvers) {
//创建自定义异常处理器对象
SimpleMappingExceptionResolver exceptionResolver = new SimpleMappingExceptionResolver();
//创建属性对象
Properties properties = new Properties();
//注入全类名异常，并指定异常逻辑视图
properties.setProperty("java.lang.ArithmeticException","error");
//将异常属性注入到异常映射中
exceptionResolver.setExceptionMappings(properties);
//将异常信息注入到请求域中，浏览器可以通过请求域获取异常信息
exceptionResolver.setExceptionAttribute("ex");
//添加异常解析器
resolvers.add(exceptionResolver);
}
}
创建自定义拦截器
@Component
public class FirstInterceptor implements HandlerInterceptor {
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
System.out.println("FirstInterceptor->preHandle");
return HandlerInterceptor.super.preHandle(request,response,handler);
}
@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
System.out.println("FirstInterceptor->postHandle");
}
@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
System.out.println("FirstInterceptor->after");
}
}
创建视图index.html
<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
<meta charset="UTF-8">
<title>首页</title>
</head>
<body>
<h1>index.html</h1>
<a th:href="@{/test/error}">测试异常处理器</a>
</body>
</html>
创建视图error.html
<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
<meta charset="UTF-8">
<title>错误</title>
</head>
<body>
<h1>error.html</h1>
<hr>
<p th:text="${ex}"/>
</body>
</html>
测试
@Controller
public class TestController {
@GetMapping("/test/error")
public String testError() {
System.out.println(10 / 0);
return "success";
}
}