Using input key filename as is.

.classpath

@@ -13,25 +13,25 @@
 	</classpathentry>
 	<classpathentry kind="src" output="target/test-classes" path="src/test/java">
 		<attributes>
+			<attribute name="test" value="true"/>
 			<attribute name="optional" value="true"/>
 			<attribute name="maven.pomderived" value="true"/>
-			<attribute name="test" value="true"/>
 		</attributes>
 	</classpathentry>
 	<classpathentry excluding="**" kind="src" output="target/test-classes" path="src/test/resources">
 		<attributes>
-			<attribute name="maven.pomderived" value="true"/>
 			<attribute name="test" value="true"/>
+			<attribute name="maven.pomderived" value="true"/>
 		</attributes>
 	</classpathentry>
-	<classpathentry kind="src" path="de.kreth.property2java"/>
+	<classpathentry exported="true" kind="con" path="org.eclipse.m2e.MAVEN2_CLASSPATH_CONTAINER">
-	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-11">
 		<attributes>
 			<attribute name="maven.pomderived" value="true"/>
 		</attributes>
 	</classpathentry>
-	<classpathentry kind="con" path="org.eclipse.m2e.MAVEN2_CLASSPATH_CONTAINER">
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-11">
 		<attributes>
+			<attribute name="module" value="true"/>
 			<attribute name="maven.pomderived" value="true"/>
 		</attributes>
 	</classpathentry>

src/main/java/de/kreth/property2java/Generator.java

@@ -1,6 +1,5 @@
 package de.kreth.property2java;
 
-import java.io.File;
 import java.io.IOException;
 import java.io.Reader;
 import java.io.Writer;
@@ -39,7 +38,7 @@ public class Generator {
 
 		for (Map.Entry<String, Reader> entry : config.getInput().entrySet()) {
 			String fileName = entry.getKey();
-			try (Writer out = config.outWriter(new File(fileName).getName())) {
+			try (Writer out = config.outWriter(fileName)) {
 
 				Properties properties = new Properties();
 				properties.load(entry.getValue());