BAEL-6754 Parameterized Logging with Slf4j (#14447)

- updated logback-classic version
- updated logback.xml to have only one appender for new classes
- added sample parameterized logging and fluent logging

logging-modules/logback/src/main/java/com/baeldung/parameterized/logging/FluentLoggingPlayground.java

@@ -0,0 +1,36 @@
+package com.baeldung.parameterized.logging;
+
+import java.time.LocalDateTime;
+import java.time.ZonedDateTime;
+
+import lombok.extern.slf4j.Slf4j;
+
+@Slf4j
+public class FluentLoggingPlayground {
+
+    public static void main(String[] args) {
+
+        Exception exceptionCause = new Exception(new IllegalArgumentException("Something unprocessable"));
+
+        log.atInfo()
+            .setMessage("App is running at {}, zone = {}")
+            .addArgument(LocalDateTime.now())
+            .addArgument(ZonedDateTime.now().getZone())
+            .log();
+
+        log.atInfo()
+            .setMessage("App is running at {}, zone = {}")
+            .addArgument(LocalDateTime.now())
+            .addArgument(ZonedDateTime.now().getZone())
+            .setCause(exceptionCause)
+            .log();
+
+        log.atInfo()
+            .setMessage("App is running at")
+            .addKeyValue("time", LocalDateTime.now())
+            .addKeyValue("zone", ZonedDateTime.now().getZone())
+            .setCause(exceptionCause)
+            .log();
+
+    }
+}

logging-modules/logback/src/main/java/com/baeldung/parameterized/logging/LoggingPlayground.java

@@ -0,0 +1,40 @@
+package com.baeldung.parameterized.logging;
+
+import java.time.LocalDateTime;
+import java.time.ZonedDateTime;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class LoggingPlayground {
+
+    public static final Logger log = LoggerFactory.getLogger(LoggingPlayground.class);
+
+    public static void main(String[] args) {
+        log.info("App is running at {}", LocalDateTime.now());
+
+        log.info("App is running at {}, zone = {}", LocalDateTime.now(), ZonedDateTime.now()
+            .getZone());
+
+        log.info("App is running at {}, zone = {}, java version = {}", LocalDateTime.now(), ZonedDateTime.now()
+            .getZone(), System.getProperty("java.version"));
+
+        log.info("App is running at {}, zone = {}, java version = {}, java vm = {}", LocalDateTime.now(), ZonedDateTime.now()
+            .getZone(), System.getProperty("java.version"), System.getProperty("java.vm.name"));
+
+        //old approach to print multiple parameters
+        log.info("App is running at {}, zone = {}, java version = {}, java vm = {}",
+            new Object[] { ZonedDateTime.now(), ZonedDateTime.now().getZone(), System.getProperty("java.version"), System.getProperty("java.vm.name") });
+
+        Exception exceptionCause = new Exception(new IllegalArgumentException("Something unprocessable"));
+
+        //exception as last parameters is considered as exception and printed with trace
+        log.info("App is running at {}, zone = {}, java version = {}, java vm = {}", LocalDateTime.now(), ZonedDateTime.now()
+            .getZone(), System.getProperty("java.version"), System.getProperty("java.vm.name"), exceptionCause);
+
+        //exception in between parameters is considered as pure parameter and printed without trace
+        log.info("App is running at {}, zone = {}, java version = {}, java vm = {}", LocalDateTime.now(), ZonedDateTime.now()
+            .getZone(), System.getProperty("java.version"), exceptionCause, System.getProperty("java.vm.name"));
+
+    }
+}

logging-modules/logback/src/main/resources/logback.xml

@@ -6,7 +6,7 @@
 
     <appender name="out" class="ch.qos.logback.core.ConsoleAppender">
         <encoder>
-            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern>
+            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg %kvp%n</pattern>
         </encoder>
     </appender>
 
@@ -66,4 +66,7 @@
         <appender-ref ref="mask" />
     </root>
 
+    <logger name="com.baeldung.parameterized.logging" additivity="false" level="INFO">
+        <appender-ref ref="out"/>
+    </logger>
 </configuration>