以下是 log4j2 与 Spring boot 集成的一个工作示例。
尝试使用 Gradle 构建，但也可以用于 maven 构建。
需要考虑的点（如果您使用的是弹簧靴）：
- 从所有配置模块中删除 Spring 默认日志记录模块
- 为 Spring Boot 添加 log4j2 启动器
- 通过向属性
logging.config= 添加值来通知 spring 有关 log4j2 配置文件的信息
- 确保 log4j2 配置符合文档要求（否则日志记录将无法按预期工作）
项目配置：
build.gradle
plugins {
id 'org.springframework.boot' version '2.5.0'
id 'io.spring.dependency-management' version '1.0.11.RELEASE'
id 'java'
id 'idea'
}
group = 'com.example'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '11'
repositories {
mavenCentral()
}
dependencies {
implementation('org.springframework.boot:spring-boot-starter-web')
implementation('org.springframework.boot:spring-boot-starter') {
exclude group: 'org.springframework.boot', module: 'spring-boot-starter-logging'
}
implementation('org.springframework.boot:spring-boot-starter-log4j2')
testImplementation 'org.springframework.boot:spring-boot-starter-test'
}
test {
useJUnitPlatform()
}
configurations {
all {
exclude group: 'org.springframework.boot', module: 'spring-boot-starter-logging'
}
}
log4j.properties
rootLogger.level = INFO
property.filename = application.log
appenders = R, console
appender.console.type = Console
appender.console.name = STDOUT
appender.console.layout.type = PatternLayout
appender.console.layout.pattern = %d %5p [%t] (%F:%L) - %m%n
appender.R.type = RollingFile
appender.R.name = File
appender.R.fileName = ${filename}
appender.R.filePattern = ${filename}.%d{yyyy-MM-dd}
appender.R.layout.type = PatternLayout
appender.R.layout.pattern = %d{yyyy-MM-dd HH:mm:ss} %c{1} [%p] %m%n
appender.R.policies.type = Policies
appender.R.policies.time.type = TimeBasedTriggeringPolicy
appender.R.policies.time.interval = 1
rootLogger.appenderRefs = R, console
rootLogger.appenderRef.console.ref = STDOUT
rootLogger.appenderRef.R.ref = File
application.properties
logging.config=classpath:log4j2.properties
AppController.java
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
@RestController
public class AppController {
private static final Logger LOG = LogManager.getLogger(AppController.class);
@RequestMapping(value = "/refresh_configs", method = RequestMethod.GET, produces = MediaType.APPLICATION_JSON_VALUE)
public ResponseEntity<?> refreshConfig() {
LOG.info("refresh_configs");
return new ResponseEntity<>("OK", HttpStatus.OK);
}
}
application.log
2021-06-12 22:39:00 HelperApplication [INFO] Starting HelperApplication using Java 11.0.9 on 88e9fe567a24 with PID 66713 (/Users/${USER}/Desktop/Helper/out/production/classes started by ${USER} in /Users/${USER}/Desktop/Helper)
2021-06-12 22:39:00 HelperApplication [INFO] No active profile set, falling back to default profiles: default
2021-06-12 22:39:01 TomcatWebServer [INFO] Tomcat initialized with port(s): 8080 (http)
2021-06-12 22:39:01 Http11NioProtocol [INFO] Initializing ProtocolHandler ["http-nio-8080"]
2021-06-12 22:39:01 StandardService [INFO] Starting service [Tomcat]
2021-06-12 22:39:01 StandardEngine [INFO] Starting Servlet engine: [Apache Tomcat/9.0.46]
2021-06-12 22:39:01 [/] [INFO] Initializing Spring embedded WebApplicationContext
2021-06-12 22:39:01 ServletWebServerApplicationContext [INFO] Root WebApplicationContext: initialization completed in 580 ms
2021-06-12 22:39:01 Http11NioProtocol [INFO] Starting ProtocolHandler ["http-nio-8080"]
2021-06-12 22:39:01 TomcatWebServer [INFO] Tomcat started on port(s): 8080 (http) with context path ''
2021-06-12 22:39:01 HelperApplication [INFO] Started HelperApplication in 1.187 seconds (JVM running for 1.944)
2021-06-12 22:39:01 ApplicationAvailabilityBean [INFO] Application availability state LivenessState changed to CORRECT
2021-06-12 22:39:01 ApplicationAvailabilityBean [INFO] Application availability state ReadinessState changed to ACCEPTING_TRAFFIC
2021-06-12 22:39:17 [/] [INFO] Initializing Spring DispatcherServlet 'dispatcherServlet'
2021-06-12 22:39:17 DispatcherServlet [INFO] Initializing Servlet 'dispatcherServlet'
2021-06-12 22:39:17 DispatcherServlet [INFO] Completed initialization in 0 ms
2021-06-12 22:39:17 AppController [INFO] refresh_configs
2021-06-12 22:49:33 AppController [INFO] refresh_configs
2021-06-12 23:01:52 ApplicationAvailabilityBean [INFO] Application availability state ReadinessState changed from ACCEPTING_TRAFFIC to REFUSING_TRAFFIC
参考：
https://stackoverflow.com/a/39703897/2987755
https://docs.spring.io/spring-boot/docs/2.0.x/reference/html/howto-logging.html#howto-configure-log4j-for-logging