这段代码可能是有用的，我从stackoverflow得到的。这段代码满足了我的要求。链接在下面。
Auto-redirect root path to Spring Boot Context Path

import java.io.IOException;
import java.util.Collections;

import org.apache.catalina.Host;
import org.apache.catalina.core.StandardContext;
import org.apache.catalina.startup.Tomcat;
import org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory;
import org.springframework.boot.web.servlet.ServletContextInitializer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import jakarta.servlet.Servlet;
import jakarta.servlet.ServletContainerInitializer;
import jakarta.servlet.ServletException;
import jakarta.servlet.http.HttpServlet;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;

@Configuration
public class RootServletConfig {

    @Bean
    public TomcatServletWebServerFactory servletWebServerFactory() {
        return new TomcatServletWebServerFactory() {

            @Override
            protected void prepareContext(Host host, ServletContextInitializer[] initializers) {
                super.prepareContext(host, initializers);
                StandardContext child = new StandardContext();
                child.addLifecycleListener(new Tomcat.FixContextListener());
                child.setPath("");
                ServletContainerInitializer initializer = getServletContextInitializer(getContextPath());
                child.addServletContainerInitializer(initializer, Collections.emptySet());
                child.setCrossContext(true);
                host.addChild(child);
            }
        };
    }

    private ServletContainerInitializer getServletContextInitializer(String contextPath) {
        return (c, context) -> {
            Servlet servlet = new HttpServlet() {
                @Override
                protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
                    resp.sendRedirect(contextPath);
                }
            };
            context.addServlet("root", servlet).addMapping("/");
        };
    }
}

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