#29 - Workspace.LineCallback now uses Optional as return type.

That allows us to replace non-null checks with a simple ….ifPresent(…).

release-tools/src/main/java/org/springframework/data/release/io/Workspace.java

@@ -30,6 +30,7 @@ import java.nio.file.Path;
 import java.nio.file.SimpleFileVisitor;
 import java.nio.file.attribute.BasicFileAttributes;
 import java.util.Arrays;
+import java.util.Optional;
 import java.util.Scanner;
 import java.util.function.Predicate;
 import java.util.stream.Stream;
@@ -190,12 +191,7 @@ public class Workspace {
 			long number = 0;
 
 			while (scanner.hasNextLine()) {
-
+				callback.doWith(scanner.nextLine(), number++).ifPresent(it -> builder.append(it).append("\n"));
-				String result = callback.doWith(scanner.nextLine(), number++);
-
-				if (result != null) {
-					builder.append(result).append("\n");
-				}
 			}
 
 			writeContentToFile(filename, project, builder.toString());
@@ -229,6 +225,6 @@ public class Workspace {
 	}
 
 	public interface LineCallback {
-		String doWith(String line, long number);
+		Optional<String> doWith(String line, long number);
 	}
 }

release-tools/src/main/java/org/springframework/data/release/misc/ReleaseOperations.java

@@ -19,6 +19,7 @@ import lombok.RequiredArgsConstructor;
 
 import java.util.Collections;
 import java.util.HashSet;
+import java.util.Optional;
 import java.util.Set;
 
 import org.springframework.data.release.git.GitOperations;
@@ -83,9 +84,9 @@ public class ReleaseOperations {
 						builder.append(line).append("\n\n");
 						builder.append(changelog.toString());
 
-						return builder.toString();
+						return Optional.of(builder.toString());
 					} else {
-						return line;
+						return Optional.of(line);
 					}
 				});
 
@@ -104,7 +105,7 @@ public class ReleaseOperations {
 		iteration.stream().forEach(module -> {
 
 			boolean processed = workspace.processFile("src/main/resources/notice.txt", module.getProject(),
-					(line, number) -> number != 0 ? line : module.toString());
+					(line, number) -> Optional.of(number != 0 ? line : module.toString()));
 
 			if (processed) {
 				logger.log(module, "Updated notice.txt.");