刚接触Spring MVC,Demo项目中,起先用的是xml的配置,基本是默认配置,这个时候启项目没问题,WEB-INF下的index.jsp也可以访问,但是用了AbstractAnnotationConfigDispatcherServletInitializer的java配置后就报错了,
代码全是按照书上来的,没有问题,但是报错Caused by: java.lang.IllegalArgumentException: Failed to register servlet with name 'dispatcher'.Check if there is another servlet registered under the same name.
代码如示
@Configuration
@EnableWebMvc
@ComponentScan("spittr.web")
public class WebConfig extends WebMvcConfigurerAdapter {
@Bean
public ViewResolver viewResolver(){
InternalResourceViewResolver resolver = new InternalResourceViewResolver();
resolver.setPrefix("/WEB-INF/views/");
resolver.setSuffix(".jsp");
resolver.setExposeContextBeansAsAttributes(true);
return resolver;
}
@Override
public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer){
configurer.enable();
}
}
public class SpittrWebAppInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {
@Override
protected Class<?>[] getRootConfigClasses() {
return new Class<?>[] { RootConfig.class };
}
@Override
protected Class<?>[] getServletConfigClasses() {
return new Class<?>[] { WebConfig.class };
}
@Override
protected String[] getServletMappings() {
return new String[]{ "/" };
}
}
@Configuration
@ComponentScan(basePackages = {"spittr"}, excludeFilters={
@Filter(type= FilterType.ANNOTATION, value = EnableWebMvc.class)
})
public class RootConfig {
}
报错信息是有两个同名的dispatcher Servlet,这是因为什么原因呢,最后发现是在添加java配置之前,Spring会从web.xml文件中得到dispatcher,但是我现在没有修改web.xml文件,又加上了java的配置,所以会有两个dispacher,Spring这个时候不知道去加载哪个,所以报错
解决方案:可以修改web.xml文件,删除其中的配置,问题就解决了