diff --git a/src/main/java/rife/bld/extension/CheckstyleOperation.java b/src/main/java/rife/bld/extension/CheckstyleOperation.java
index ed8a610..97eeb55 100644
--- a/src/main/java/rife/bld/extension/CheckstyleOperation.java
+++ b/src/main/java/rife/bld/extension/CheckstyleOperation.java
@@ -250,7 +250,8 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
             if (!exclude_.isEmpty()) {
                 for (var e : exclude_) {
                     if (e.exists()) {
-                        args.add("-e " + e.getAbsolutePath());
+                        args.add("-e");
+                        args.add(e.getAbsolutePath());
                     }
                 }
             }
@@ -258,7 +259,8 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
             if (!excludeRegex_.isEmpty()) {
                 for (var e : excludeRegex_) {
                     if (isNotBlank(e)) {
-                        args.add("-x " + e);
+                        args.add("-x");
+                        args.add(e);
                     }
                 }
             }
diff --git a/src/test/java/rife/bld/extension/CheckstyleOperationTest.java b/src/test/java/rife/bld/extension/CheckstyleOperationTest.java
index b6f05c3..5c3f299 100644
--- a/src/test/java/rife/bld/extension/CheckstyleOperationTest.java
+++ b/src/test/java/rife/bld/extension/CheckstyleOperationTest.java
@@ -125,27 +125,27 @@ class CheckstyleOperationTest {
         var e = "-e ";
 
         var op = new CheckstyleOperation().fromProject(new Project()).exclude(SRC_MAIN_JAVA, SRC_TEST_JAVA);
-        assertThat(op.executeConstructProcessCommandList()).as("String...")
+        assertThat(String.join(" ", op.executeConstructProcessCommandList())).as("String...")
                 .contains(e + foo.getAbsolutePath()).contains(e + bar.getAbsolutePath());
 
         op = new CheckstyleOperation().fromProject(new Project()).excludeStrings(List.of(SRC_MAIN_JAVA, SRC_TEST_JAVA));
-        assertThat(op.executeConstructProcessCommandList()).as("List(String...)")
+        assertThat(String.join(" ", op.executeConstructProcessCommandList())).as("List(String...)")
                 .contains(e + foo.getAbsolutePath()).contains(e + bar.getAbsolutePath());
 
         op = new CheckstyleOperation().fromProject(new Project()).exclude(foo, bar);
-        assertThat(op.executeConstructProcessCommandList()).as("File...")
+        assertThat(String.join(" ", op.executeConstructProcessCommandList())).as("File...")
                 .contains(e + foo.getAbsolutePath()).contains(e + bar.getAbsolutePath());
 
         op = new CheckstyleOperation().fromProject(new Project()).exclude(List.of(foo, bar));
-        assertThat(op.executeConstructProcessCommandList()).as("List(File...)")
+        assertThat(String.join(" ", op.executeConstructProcessCommandList())).as("List(File...)")
                 .contains(e + foo.getAbsolutePath()).contains(e + bar.getAbsolutePath());
 
         op = new CheckstyleOperation().fromProject(new Project()).exclude(foo.toPath(), bar.toPath());
-        assertThat(op.executeConstructProcessCommandList()).as("Path...")
+        assertThat(String.join(" ", op.executeConstructProcessCommandList())).as("Path...")
                 .contains(e + foo.getAbsolutePath()).contains(e + bar.getAbsolutePath());
 
         op = new CheckstyleOperation().fromProject(new Project()).excludePaths(List.of(foo.toPath(), bar.toPath()));
-        assertThat(op.executeConstructProcessCommandList()).as("List(Path...)")
+        assertThat(String.join(" ", op.executeConstructProcessCommandList())).as("List(Path...)")
                 .contains(e + foo.getAbsolutePath()).contains(e + bar.getAbsolutePath());
     }
 
@@ -153,10 +153,10 @@ class CheckstyleOperationTest {
     void excludeRegex() {
         var op = new CheckstyleOperation().fromProject(new Project()).excludeRegex(FOO, BAR);
         var x = "-x ";
-        assertThat(op.executeConstructProcessCommandList()).contains(x + FOO, x + BAR);
+        assertThat(String.join(" ", op.executeConstructProcessCommandList())).contains(x + FOO, x + BAR);
 
         op = new CheckstyleOperation().fromProject(new Project()).excludeRegex(List.of(FOO, BAR));
-        assertThat(op.executeConstructProcessCommandList()).as("as list").contains(x + FOO, x + BAR);
+        assertThat(String.join(" ", op.executeConstructProcessCommandList())).as("as list").contains(x + FOO, x + BAR);
     }
 
     @Test