由于org.apache.logging.log4j.LoggingException引起：log4j-slf4j-impl不能与log4j-to-slf4j同时存在。

在我的Spring Boot 2项目中：

在build.gradle中：

dependencies {
    implementation 'com.google.code.gson:gson:2.7'
    implementation 'com.h2database:h2'
    implementation 'javax.servlet:jstl:1.2'
    implementation 'org.springframework.boot:spring-boot-devtools'
    implementation('org.springframework.boot:spring-boot-starter') {
        exclude group: 'org.springframework.boot', module: 'spring-boot-starter-logging'
    }
    implementation 'org.springframework.boot:spring-boot-starter-actuator'
    implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
    implementation 'org.springframework.boot:spring-boot-starter-log4j2'
    implementation 'org.springframework.boot:spring-boot-starter-jdbc'
    implementation 'org.springframework.boot:spring-boot-starter-security'
    implementation 'org.springframework.boot:spring-boot-starter-thymeleaf'
    implementation "org.springframework.boot:spring-boot-starter-web"
    testImplementation('org.springframework.boot:spring-boot-starter-test') {
        exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'
    }
    testImplementation 'org.junit.jupiter:junit-jupiter:5.5.2'
}

在src/resources/log4j2.xml中：

在我的控制器中：

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
@Controller
public class CategoryController {
    private CategoryRepository categoryRepository;
    private static Logger logger = LoggerFactory.getLogger(CategoryController.class);
    
    @GetMapping("/categories")
    public String getCategories(Model model) {
        logger.debug("getCategories>>>>>>>>>>>>>>>>");
        model.addAttribute("categoryList", this.categoryRepository.findAll());
        return "categories/category_list";
    }
}

但是当我启动项目时出现错误：

Caused by: org.apache.logging.log4j.LoggingException: log4j-slf4j-impl
  cannot be present with log4j-to-slf4j