Removed some clutter

log-mdc-ndc/src/main/java/com/baeldung/mdc/BusinessService.java

@@ -1,9 +1,26 @@
 package com.baeldung.mdc;
 
-public interface BusinessService {
+/**
-
+ * A fake {@link IBusinessService} simulating an actual one.
-	/** Sample service transferring a given amount of money. 
+ */
-	 * @return {@code true} when the transfer complete successfully, {@code false} otherwise. */
+public abstract class BusinessService implements IBusinessService {
-	boolean transfer(long amount);
 
+    public boolean transfer(long amount) {
+        beforeTransfer(amount);
+        // exchange messages with a remote system to transfer the money
+        try {
+            // let's pause randomly to properly simulate an actual system.
+            Thread.sleep((long) (500 + Math.random() * 500));
+        } catch (InterruptedException e) {
+            // should never happen
+        }
+        // let's simulate both failing and successful transfers
+        boolean outcome = Math.random() >= 0.25;
+        afterTransfer(amount, outcome);
+        return outcome;
+    }
+
+    abstract protected void beforeTransfer(long amount);
+
+    abstract protected void afterTransfer(long amount, boolean outcome);
 }

log-mdc-ndc/src/main/java/com/baeldung/mdc/DefaultBusinessService.java

@@ -1,19 +0,0 @@
-package com.baeldung.mdc;
-
-/**
- * A fake {@link BusinessService} simulating an actual one.
- */
-public class DefaultBusinessService implements BusinessService {
-
-	public boolean transfer(long amount) {
-		try {
-			// let's pause randomly to properly simulate an actual system. 
-			Thread.sleep((long) (500 + Math.random()*500));
-		} catch (InterruptedException e) {
-			// should never happen
-		}
-		// let's simulate both failing and successful transfers 
-		return Math.random() >= 0.25;
-	}
-
-}

log-mdc-ndc/src/main/java/com/baeldung/mdc/DelegateBusiness.java

@@ -1,29 +0,0 @@
-package com.baeldung.mdc;
-
-public abstract class DelegateBusiness {
-	
-	private BusinessService delegate = null;
-
-	public DelegateBusiness(BusinessService delegate) {
-		super();
-		this.delegate = delegate;
-	}
-	
-	public DelegateBusiness() {
-		this( new DefaultBusinessService() );
-	}
-
-	public boolean transfer(long amount) {
-		preTransfer(amount);
-		boolean outcome = delegate.transfer(amount);
-		postTransfer(amount, outcome);
-		return outcome;
-	}
-
-	abstract protected void postTransfer(long amount, boolean outcome);
-
-	abstract protected void preTransfer(long amount);
-	
-	
-	
-}

log-mdc-ndc/src/main/java/com/baeldung/mdc/IBusinessService.java

@@ -0,0 +1,9 @@
+package com.baeldung.mdc;
+
+public interface IBusinessService {
+
+	/** Sample service transferring a given amount of money. 
+	 * @return {@code true} when the transfer complete successfully, {@code false} otherwise. */
+	boolean transfer(long amount);
+
+}

log-mdc-ndc/src/main/java/com/baeldung/mdc/log4j/Log4JBusinessService.java

@@ -3,19 +3,19 @@ package com.baeldung.mdc.log4j;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
-import com.baeldung.mdc.DelegateBusiness;
+import com.baeldung.mdc.BusinessService;
 
-final class Log4JBusinessService extends DelegateBusiness {
+class Log4JBusinessService extends BusinessService {
 	
 	private static final Logger logger = LogManager.getLogger();
 
 	@Override
-	protected void preTransfer(long amount) {
+	protected void beforeTransfer(long amount) {
 		logger.info("Preparing to transfer {}$.");
 	}
 
 	@Override
-	protected void postTransfer(long amount, boolean outcome) {
+	protected void afterTransfer(long amount, boolean outcome) {
 		logger.info("Has transfer of {}$ completed successfully ? {}.");
 	}
 	

log-mdc-ndc/src/main/java/com/baeldung/mdc/log4j2/Log4J2BusinessService.java

@@ -2,19 +2,19 @@ package com.baeldung.mdc.log4j2;
 
 import org.apache.log4j.Logger;
 
-import com.baeldung.mdc.DelegateBusiness;
+import com.baeldung.mdc.BusinessService;
 
-final class Log4J2BusinessService extends DelegateBusiness {
+final class Log4J2BusinessService extends BusinessService {
 	
 	private Logger logger = Logger.getLogger(Log4J2BusinessService.class);
 
 	@Override
-	protected void preTransfer(long amount) {
+	protected void beforeTransfer(long amount) {
 		logger .info("Preparing to transfer " + amount + "$.");
 	}
 
 	@Override
-	protected void postTransfer(long amount, boolean outcome) {
+	protected void afterTransfer(long amount, boolean outcome) {
 		logger.info("Has transfer of " + amount + "$ completed successfully ? " + outcome + ".");
 	}
 	

log-mdc-ndc/src/main/java/com/baeldung/mdc/slf4j/Slf4jBusinessService.java

@@ -3,19 +3,19 @@ package com.baeldung.mdc.slf4j;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import com.baeldung.mdc.DelegateBusiness;
+import com.baeldung.mdc.BusinessService;
 
-final class Slf4jBusinessService extends DelegateBusiness {
+final class Slf4jBusinessService extends BusinessService {
 	
 	private static final Logger logger = LoggerFactory.getLogger(Slf4jBusinessService.class);
 
 	@Override
-	protected void preTransfer(long amount) {
+	protected void beforeTransfer(long amount) {
 		logger.info("Preparing to transfer " + amount + "$.");
 	}
 
 	@Override
-	protected void postTransfer(long amount, boolean outcome) {
+	protected void afterTransfer(long amount, boolean outcome) {
 		logger.info("Has transfer of " + amount + "$ completed successfully ? " + outcome + ".");
 	}