diff --git a/.github/workflows/bld.yml b/.github/workflows/bld.yml
index c0ba763..bf65051 100644
--- a/.github/workflows/bld.yml
+++ b/.github/workflows/bld.yml
@@ -22,11 +22,8 @@ jobs:
           distribution: "zulu"
           java-version: ${{ matrix.java-version }}
 
-      - name: Grant execute permission for bld
-        run: chmod +x bld
-
-      - name: Download the dependencies
+      - name: Download dependencies
         run: ./bld download
 
-      - name: Run tests with bld
+      - name: Run tests
         run: ./bld compile test
diff --git a/.idea/libraries/bld.xml b/.idea/libraries/bld.xml
index a2969be..2fb5ff0 100644
--- a/.idea/libraries/bld.xml
+++ b/.idea/libraries/bld.xml
@@ -2,12 +2,12 @@
   <library name="bld">
     <CLASSES>
       <root url="file://$PROJECT_DIR$/lib/bld" />
-      <root url="jar://$USER_HOME$/.bld/dist/bld-1.9.1.jar!/" />
+      <root url="jar://$USER_HOME$/.bld/dist/bld-2.0.0-SNAPSHOT.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES>
       <root url="file://$PROJECT_DIR$/lib/bld" />
-      <root url="jar://$USER_HOME$/.bld/dist/bld-1.9.1-sources.jar!/" />
+      <root url="jar://$USER_HOME$/.bld/dist/bld-2.0.0-SNAPSHOT-sources.jar!/" />
     </SOURCES>
     <excluded>
       <root url="jar://$PROJECT_DIR$/lib/bld/bld-wrapper.jar!/" />
diff --git a/.vscode/settings.json b/.vscode/settings.json
index 87dd394..fc389ce 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -9,7 +9,7 @@
     ],
     "java.configuration.updateBuildConfiguration": "automatic",
     "java.project.referencedLibraries": [
-        "${HOME}/.bld/dist/bld-1.9.1.jar",
+        "${HOME}/.bld/dist/bld-2.0.0-SNAPSHOT.jar",
         "lib/**/*.jar"
     ],
     "java.compile.nullAnalysis.mode": "automatic"
diff --git a/examples/.idea/libraries/bld.xml b/examples/.idea/libraries/bld.xml
index a2969be..2fb5ff0 100644
--- a/examples/.idea/libraries/bld.xml
+++ b/examples/.idea/libraries/bld.xml
@@ -2,12 +2,12 @@
   <library name="bld">
     <CLASSES>
       <root url="file://$PROJECT_DIR$/lib/bld" />
-      <root url="jar://$USER_HOME$/.bld/dist/bld-1.9.1.jar!/" />
+      <root url="jar://$USER_HOME$/.bld/dist/bld-2.0.0-SNAPSHOT.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES>
       <root url="file://$PROJECT_DIR$/lib/bld" />
-      <root url="jar://$USER_HOME$/.bld/dist/bld-1.9.1-sources.jar!/" />
+      <root url="jar://$USER_HOME$/.bld/dist/bld-2.0.0-SNAPSHOT-sources.jar!/" />
     </SOURCES>
     <excluded>
       <root url="jar://$PROJECT_DIR$/lib/bld/bld-wrapper.jar!/" />
diff --git a/examples/.idea/misc.xml b/examples/.idea/misc.xml
index 97c1009..a01a1f3 100644
--- a/examples/.idea/misc.xml
+++ b/examples/.idea/misc.xml
@@ -1,4 +1,8 @@
 <project version="4">
+  <component name="EntryPointsManager">
+    <pattern value="com.example.ExamplesBuild" method="checkstyle" />
+    <pattern value="com.example.ExamplesBuild" />
+  </component>
   <component name="PDMPlugin">
     <option name="customRuleSets">
       <list>
diff --git a/examples/.vscode/settings.json b/examples/.vscode/settings.json
index d136e4d..33a9922 100644
--- a/examples/.vscode/settings.json
+++ b/examples/.vscode/settings.json
@@ -9,7 +9,7 @@
     ],
     "java.configuration.updateBuildConfiguration": "automatic",
     "java.project.referencedLibraries": [
-        "${HOME}/.bld/dist/bld-1.9.1.jar",
+        "${HOME}/.bld/dist/bld-2.0.0-SNAPSHOT.jar",
         "lib/**/*.jar"
     ]
 }
diff --git a/examples/lib/bld/bld-wrapper.jar b/examples/lib/bld/bld-wrapper.jar
index f53e8c7..830aee8 100644
Binary files a/examples/lib/bld/bld-wrapper.jar and b/examples/lib/bld/bld-wrapper.jar differ
diff --git a/examples/lib/bld/bld-wrapper.properties b/examples/lib/bld/bld-wrapper.properties
index d36e73a..5633541 100644
--- a/examples/lib/bld/bld-wrapper.properties
+++ b/examples/lib/bld/bld-wrapper.properties
@@ -1,7 +1,7 @@
 bld.downloadExtensionJavadoc=false
 bld.downloadExtensionSources=true
-bld.extensions=com.uwyn.rife2:bld-checkstyle:1.0.1
-bld.repositories=MAVEN_LOCAL,MAVEN_CENTRAL,RIFE2_SNAPSHOTS,RIFE2_RELEASES
 bld.downloadLocation=
+bld.extension-checkstyle=com.uwyn.rife2:bld-checkstyle:1.0.1
+bld.repositories=MAVEN_LOCAL,MAVEN_CENTRAL,RIFE2_SNAPSHOTS,RIFE2_RELEASES
 bld.sourceDirectories=
-bld.version=1.9.1
+bld.version=2.0.0-SNAPSHOT
diff --git a/lib/bld/bld-wrapper.jar b/lib/bld/bld-wrapper.jar
index 78f3d8f..953ea9a 100644
Binary files a/lib/bld/bld-wrapper.jar and b/lib/bld/bld-wrapper.jar differ
diff --git a/lib/bld/bld-wrapper.properties b/lib/bld/bld-wrapper.properties
index d8197e2..9d4088a 100644
--- a/lib/bld/bld-wrapper.properties
+++ b/lib/bld/bld-wrapper.properties
@@ -1,9 +1,9 @@
 bld.downloadExtensionJavadoc=false
 bld.downloadExtensionSources=true
-bld.extension-pmd=com.uwyn.rife2:bld-pmd:0.9.9
-bld.extension-jacoco=com.uwyn.rife2:bld-jacoco-report:0.9.5
-bld.extension-exec=com.uwyn.rife2:bld-exec:1.0.0
-bld.repositories=MAVEN_CENTRAL,MAVEN_LOCAL,RIFE2_SNAPSHOTS,RIFE2_RELEASES
 bld.downloadLocation=
+bld.extension-exec=com.uwyn.rife2:bld-exec:1.0.1
+bld.extension-jacoco=com.uwyn.rife2:bld-jacoco-report:0.9.6
+bld.extension-pmd=com.uwyn.rife2:bld-pmd:1.1.2
+bld.repositories=MAVEN_CENTRAL,MAVEN_LOCAL,RIFE2_SNAPSHOTS,RIFE2_RELEASES
 bld.sourceDirectories=
-bld.version=1.9.1
+bld.version=2.0.0-SNAPSHOT
diff --git a/src/bld/java/rife/bld/extension/CheckstyleOperationBuild.java b/src/bld/java/rife/bld/extension/CheckstyleOperationBuild.java
index 2ef6a10..79ed47e 100644
--- a/src/bld/java/rife/bld/extension/CheckstyleOperationBuild.java
+++ b/src/bld/java/rife/bld/extension/CheckstyleOperationBuild.java
@@ -25,8 +25,7 @@ import rife.bld.publish.PublishScm;
 import java.io.IOException;
 import java.util.List;
 
-import static rife.bld.dependencies.Repository.MAVEN_CENTRAL;
-import static rife.bld.dependencies.Repository.RIFE2_RELEASES;
+import static rife.bld.dependencies.Repository.*;
 import static rife.bld.dependencies.Scope.compile;
 import static rife.bld.dependencies.Scope.test;
 import static rife.bld.operations.JavadocOptions.DocLinkOption.NO_MISSING;
@@ -35,20 +34,20 @@ public class CheckstyleOperationBuild extends Project {
     public CheckstyleOperationBuild() {
         pkg = "rife.bld.extension";
         name = "CheckstyleOperation";
-        version = version(1, 0, 1);
+        version = version(1, 0, 2, "SNAPSHOT");
 
         javaRelease = 17;
         downloadSources = true;
         autoDownloadPurge = true;
-        repositories = List.of(MAVEN_CENTRAL, RIFE2_RELEASES);
+        repositories = List.of(MAVEN_LOCAL, MAVEN_CENTRAL, RIFE2_RELEASES, RIFE2_SNAPSHOTS);
 
         scope(compile)
-                .include(dependency("com.uwyn.rife2", "bld", version(1, 9, 1)));
+                .include(dependency("com.uwyn.rife2", "bld", version(2, 0, 0, "SNAPSHOT")));
         scope(test)
                 .include(dependency("com.puppycrawl.tools", "checkstyle", version(10, 17, 0)))
-                .include(dependency("org.junit.jupiter", "junit-jupiter", version(5, 10, 2)))
-                .include(dependency("org.junit.platform", "junit-platform-console-standalone", version(1, 10, 2)))
-                .include(dependency("org.assertj", "assertj-core", version(3, 26, 0)));
+                .include(dependency("org.junit.jupiter", "junit-jupiter", version(5, 10, 3)))
+                .include(dependency("org.junit.platform", "junit-platform-console-standalone", version(1, 10, 3)))
+                .include(dependency("org.assertj", "assertj-core", version(3, 26, 3)));
         javadocOperation()
                 .javadocOptions()
                 .author()
@@ -90,14 +89,14 @@ public class CheckstyleOperationBuild extends Project {
     }
 
     @BuildCommand(summary = "Generates JaCoCo Reports")
-    public void jacoco() throws IOException {
+    public void jacoco() throws Exception {
         new JacocoReportOperation()
                 .fromProject(this)
                 .execute();
     }
 
     @BuildCommand(summary = "Runs PMD analysis")
-    public void pmd() {
+    public void pmd() throws Exception {
         new PmdOperation()
                 .fromProject(this)
                 .failOnViolation(true)
diff --git a/src/main/java/rife/bld/extension/CheckstyleOperation.java b/src/main/java/rife/bld/extension/CheckstyleOperation.java
index 7e07690..7959d0b 100644
--- a/src/main/java/rife/bld/extension/CheckstyleOperation.java
+++ b/src/main/java/rife/bld/extension/CheckstyleOperation.java
@@ -17,11 +17,15 @@
 package rife.bld.extension;
 
 import rife.bld.BaseProject;
+import rife.bld.extension.checkstyle.OutputFormat;
 import rife.bld.operations.AbstractProcessOperation;
+import rife.bld.operations.exceptions.ExitStatusException;
 
-import java.nio.file.Path;
+import java.io.File;
+import java.io.IOException;
 import java.util.*;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.logging.Level;
 import java.util.logging.Logger;
 
 /**
@@ -32,16 +36,11 @@ import java.util.logging.Logger;
  */
 public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOperation> {
     private static final Logger LOGGER = Logger.getLogger(CheckstyleOperation.class.getName());
-    protected final List<String> exclude = new ArrayList<>();
-    protected final List<String> excludeRegex = new ArrayList<>();
-    /**
-     * The command line options.
-     */
-    protected final Map<String, String> options = new ConcurrentHashMap<>();
-    /**
-     * The source files(s) or folder(s).
-     */
-    protected final Set<String> sourceDirs = new TreeSet<>();
+    private final Collection<String> excludeRegex_ = new ArrayList<>();
+    private final Collection<File> exclude_ = new ArrayList<>();
+    private final Map<String, String> options_ = new ConcurrentHashMap<>();
+    private final Set<File> sourceDir_ = new TreeSet<>();
+
     private BaseProject project_;
 
     /**
@@ -52,7 +51,7 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      */
     public CheckstyleOperation branchMatchingXpath(String xPathQuery) {
         if (isNotBlank(xPathQuery)) {
-            options.put("-b", xPathQuery);
+            options_.put("-b", xPathQuery);
         }
         return this;
     }
@@ -67,11 +66,23 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      */
     public CheckstyleOperation configurationFile(String file) {
         if (isNotBlank(file)) {
-            options.put("-c", file);
+            options_.put("-c", file);
         }
         return this;
     }
 
+    /**
+     * Specifies the location of the file that defines the configuration modules. The location can either be a
+     * filesystem location, or a name passed to the {@link ClassLoader#getResource(String) ClassLoader.getResource() }
+     * method. A configuration file is required.
+     *
+     * @param file the file
+     * @return the checkstyle operation
+     */
+    public CheckstyleOperation configurationFile(File file) {
+        return configurationFile(file.getAbsolutePath());
+    }
+
     /**
      * Prints all debug logging of CheckStyle utility.
      *
@@ -80,9 +91,9 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      */
     public CheckstyleOperation debug(boolean isDebug) {
         if (isDebug) {
-            options.put("-d", "");
+            options_.put("-d", "");
         } else {
-            options.remove("-d");
+            options_.remove("-d");
         }
         return this;
     }
@@ -96,11 +107,20 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      * @see #sourceDir(Collection)
      */
     public CheckstyleOperation exclude(String... path) {
-        for (var p : path) {
-            if (isNotBlank(p)) {
-                exclude.add(p);
-            }
-        }
+        exclude_.addAll(Arrays.stream(path).map(File::new).toList());
+        return this;
+    }
+
+    /**
+     * Directory/file to exclude from CheckStyle. The path can be the full, absolute path, or relative to the current
+     * path. Multiple excludes are allowed.
+     *
+     * @param path one or more paths
+     * @return the checkstyle operation
+     * @see #sourceDir(Collection)
+     */
+    public CheckstyleOperation exclude(File... path) {
+        exclude_.addAll(List.of(path));
         return this;
     }
 
@@ -112,12 +132,8 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      * @return the checkstyle operation
      * @see #exclude(String...)
      */
-    public CheckstyleOperation exclude(Collection<String> paths) {
-        for (var p : paths) {
-            if (isNotBlank(p)) {
-                exclude.add(p);
-            }
-        }
+    public CheckstyleOperation exclude(Collection<File> paths) {
+        exclude_.addAll(paths);
         return this;
     }
 
@@ -129,12 +145,7 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      * @see #excludeRegex(Collection)
      */
     public CheckstyleOperation excludeRegex(String... regex) {
-        for (var r : regex) {
-            if (isNotBlank(r)) {
-                excludeRegex.add(r);
-            }
-        }
-
+        excludeRegex_.addAll(List.of(regex));
         return this;
     }
 
@@ -146,61 +157,72 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      * @see #excludeRegex(String...)
      */
     public CheckstyleOperation excludeRegex(Collection<String> regex) {
-        for (var r : regex) {
-            if (isNotBlank(r)) {
-                excludeRegex.add(r);
-            }
-        }
-
+        excludeRegex_.addAll(regex);
         return this;
     }
 
+    @Override
+    public void execute() throws IOException, InterruptedException, ExitStatusException {
+        if (project_ == null) {
+            if (LOGGER.isLoggable(Level.SEVERE) && !silent()) {
+                LOGGER.severe("A project must be specified.");
+            }
+            throw new ExitStatusException(ExitStatusException.EXIT_FAILURE);
+        } else {
+            super.execute();
+        }
+    }
+
     /**
      * Part of the {@link #execute} operation, constructs the command list
      * to use for building the process.
      */
     @Override
     protected List<String> executeConstructProcessCommandList() {
-        if (project_ == null) {
-            LOGGER.severe("A project must be specified.");
-        } else if (sourceDirs.isEmpty()) {
-            sourceDirs.add(project_.srcMainJavaDirectory().getPath());
-            sourceDirs.add(project_.srcTestJavaDirectory().getPath());
-        }
-
         final List<String> args = new ArrayList<>();
-        args.add(javaTool());
 
-        args.add("-cp");
-        args.add(String.format("%s:%s:%s:%s", Path.of(project_.libTestDirectory().getPath(), "*"),
-                Path.of(project_.libCompileDirectory().getPath(), "*"), project_.buildMainDirectory(),
-                project_.buildTestDirectory()));
-        args.add("com.puppycrawl.tools.checkstyle.Main");
-
-        options.forEach((k, v) -> {
-            args.add(k);
-            if (!v.isEmpty()) {
-                args.add(v);
+        if (project_ != null) {
+            if (sourceDir_.isEmpty()) {
+                sourceDir_.add(project_.srcMainJavaDirectory());
+                sourceDir_.add(project_.srcTestJavaDirectory());
             }
-        });
+            args.add(javaTool());
 
-        if (!exclude.isEmpty()) {
-            for (var e : exclude) {
-                if (isNotBlank(e)) {
-                    args.add("-e " + e);
+            args.add("-cp");
+            args.add(String.format("%s:%s:%s:%s", new File(project_.libTestDirectory(), "*"),
+                    new File(project_.libCompileDirectory(), "*"), project_.buildMainDirectory(),
+                    project_.buildTestDirectory()));
+            args.add("com.puppycrawl.tools.checkstyle.Main");
+
+            options_.forEach((k, v) -> {
+                args.add(k);
+                if (!v.isEmpty()) {
+                    args.add(v);
+                }
+            });
+
+            if (!exclude_.isEmpty()) {
+                for (var e : exclude_) {
+                    if (e.exists()) {
+                        args.add("-e " + e.getAbsolutePath());
+                    }
                 }
             }
-        }
 
-        if (!excludeRegex.isEmpty()) {
-            for (var e : excludeRegex) {
-                if (isNotBlank(e)) {
-                    args.add("-x " + e);
+            if (!excludeRegex_.isEmpty()) {
+                for (var e : excludeRegex_) {
+                    if (isNotBlank(e)) {
+                        args.add("-x " + e);
+                    }
                 }
             }
-        }
 
-        args.addAll(sourceDirs);
+            args.addAll(sourceDir_.stream().map(File::getAbsolutePath).toList());
+
+            if (LOGGER.isLoggable(Level.FINE)) {
+                LOGGER.log(Level.FINE, String.join(" ", args));
+            }
+        }
 
         return args;
     }
@@ -222,25 +244,25 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      */
     public CheckstyleOperation executeIgnoredModules(boolean isAllowIgnoreModules) {
         if (isAllowIgnoreModules) {
-            options.put("-E", "");
+            options_.put("-E", "");
         } else {
-            options.remove("-E");
+            options_.remove("-E");
         }
         return this;
     }
 
     /**
-     * Specifies the output format. Valid values: {@link CheckstyleFormatOption#XML},
-     * {@link CheckstyleFormatOption#SARIF}, {@link CheckstyleFormatOption#PLAIN} for the XML, sarif and default logger
+     * Specifies the output format. Valid values: {@link OutputFormat#XML},
+     * {@link OutputFormat#SARIF}, {@link OutputFormat#PLAIN} for the XML, sarif and default logger
      * respectively.
      * <p>
-     * Defaults to {@link CheckstyleFormatOption#PLAIN}.
+     * Defaults to {@link OutputFormat#PLAIN}.
      *
      * @param format the output format
      * @return the checkstyle operation
      */
-    public CheckstyleOperation format(CheckstyleFormatOption format) {
-        options.put("-f", format.label.toLowerCase());
+    public CheckstyleOperation format(OutputFormat format) {
+        options_.put("-f", format.label.toLowerCase());
         return this;
     }
 
@@ -255,9 +277,9 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      */
     public CheckstyleOperation generateXpathSuppression(boolean xPathSuppression) {
         if (xPathSuppression) {
-            options.put("-g", "");
+            options_.put("-g", "");
         } else {
-            options.remove("-g");
+            options_.remove("-g");
         }
         return this;
     }
@@ -279,13 +301,22 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      */
     public CheckstyleOperation javadocTree(boolean isTree) {
         if (isTree) {
-            options.put("-j", "");
+            options_.put("-j", "");
         } else {
-            options.remove("-j");
+            options_.remove("-j");
         }
         return this;
     }
 
+    /**
+     * Returns the command line options.
+     *
+     * @return the command line options
+     */
+    public Map<String, String> options() {
+        return options_;
+    }
+
     /**
      * Sets the output file.
      * <p>
@@ -296,11 +327,23 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      */
     public CheckstyleOperation outputPath(String file) {
         if (isNotBlank(file)) {
-            options.put("-o", file);
+            options_.put("-o", file);
         }
         return this;
     }
 
+    /**
+     * Sets the output file.
+     * <p>
+     * Defaults to stdout.
+     *
+     * @param file the output file
+     * @return the checkstyle operation
+     */
+    public CheckstyleOperation outputPath(File file) {
+        return outputPath(file.getAbsolutePath());
+    }
+
     /**
      * Sets the property files to load.
      *
@@ -309,11 +352,21 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      */
     public CheckstyleOperation propertiesFile(String file) {
         if (isNotBlank(file)) {
-            options.put("-p", file);
+            options_.put("-p", file);
         }
         return this;
     }
 
+    /**
+     * Sets the property files to load.
+     *
+     * @param file the file
+     * @return the checkstyle operation
+     */
+    public CheckstyleOperation propertiesFile(File file) {
+        return propertiesFile(file.getAbsolutePath());
+    }
+
     /**
      * Specified the file(s) or folder(s) containing the source files to check.
      *
@@ -322,7 +375,19 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      * @see #sourceDir(Collection)
      */
     public CheckstyleOperation sourceDir(String... dir) {
-        sourceDirs.addAll(Arrays.stream(dir).filter(this::isNotBlank).toList());
+        sourceDir_.addAll(Arrays.stream(dir).map(File::new).toList());
+        return this;
+    }
+
+    /**
+     * Specified the file(s) or folder(s) containing the source files to check.
+     *
+     * @param dir one or more directories
+     * @return the checkstyle operation
+     * @see #sourceDir(Collection)
+     */
+    public CheckstyleOperation sourceDir(File... dir) {
+        sourceDir_.addAll(List.of(dir));
         return this;
     }
 
@@ -333,11 +398,20 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      * @return the checkstyle operation
      * @see #sourceDir(String...)
      */
-    public CheckstyleOperation sourceDir(Collection<String> dirs) {
-        sourceDirs.addAll(dirs.stream().filter(this::isNotBlank).toList());
+    public CheckstyleOperation sourceDir(Collection<File> dirs) {
+        sourceDir_.addAll(dirs);
         return this;
     }
 
+    /**
+     * Returns the file(s) or folders(s) containing the sources files to check
+     *
+     * @return the files or directories
+     */
+    public Set<File> sourceDir() {
+        return sourceDir_;
+    }
+
     /**
      * Prints xpath suppressions at the file's line and column position. Argument is the line and column number
      * (separated by a {@code :} ) in the file that the suppression should be generated for. The option cannot be
@@ -352,7 +426,7 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      */
     public CheckstyleOperation suppressionLineColumnNumber(String lineColumnNumber) {
         if (isNotBlank(lineColumnNumber)) {
-            options.put("-s", lineColumnNumber);
+            options_.put("-s", lineColumnNumber);
         }
         return this;
     }
@@ -367,7 +441,7 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      * @return the checkstyle operation
      */
     public CheckstyleOperation tabWith(int length) {
-        options.put("-w", String.valueOf(length));
+        options_.put("-w", String.valueOf(length));
         return this;
     }
 
@@ -380,9 +454,9 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      */
     public CheckstyleOperation tree(boolean isTree) {
         if (isTree) {
-            options.put("-t", "");
+            options_.put("-t", "");
         } else {
-            options.remove("-t");
+            options_.remove("-t");
         }
         return this;
     }
@@ -396,9 +470,9 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      */
     public CheckstyleOperation treeWithComments(boolean isTree) {
         if (isTree) {
-            options.put("-T", "");
+            options_.put("-T", "");
         } else {
-            options.remove("-T");
+            options_.remove("-T");
         }
         return this;
     }
@@ -412,9 +486,9 @@ public class CheckstyleOperation extends AbstractProcessOperation<CheckstyleOper
      */
     public CheckstyleOperation treeWithJavadoc(boolean isTree) {
         if (isTree) {
-            options.put("-J", "");
+            options_.put("-J", "");
         } else {
-            options.remove("-J");
+            options_.remove("-J");
         }
         return this;
     }
diff --git a/src/main/java/rife/bld/extension/CheckstyleFormatOption.java b/src/main/java/rife/bld/extension/checkstyle/OutputFormat.java
similarity index 82%
rename from src/main/java/rife/bld/extension/CheckstyleFormatOption.java
rename to src/main/java/rife/bld/extension/checkstyle/OutputFormat.java
index 09ad8ac..c37a585 100644
--- a/src/main/java/rife/bld/extension/CheckstyleFormatOption.java
+++ b/src/main/java/rife/bld/extension/checkstyle/OutputFormat.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2023-2004 the original author or authors.
+ * Copyright 2023-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -14,19 +14,19 @@
  * limitations under the License.
  */
 
-package rife.bld.extension;
+package rife.bld.extension.checkstyle;
 
 /**
  * The Checkstyle output format for XML, sarif and default (plaib) logger.
  */
-public enum CheckstyleFormatOption {
+public enum OutputFormat {
     XML("xml"),
     SARIF("sarif"),
     PLAIN("plain");
 
     public final String label;
 
-    CheckstyleFormatOption(String label) {
+    OutputFormat(String label) {
         this.label = label;
     }
 }
\ No newline at end of file
diff --git a/src/test/java/rife/bld/extension/CheckstyleOperationTest.java b/src/test/java/rife/bld/extension/CheckstyleOperationTest.java
index db4ec48..578846f 100644
--- a/src/test/java/rife/bld/extension/CheckstyleOperationTest.java
+++ b/src/test/java/rife/bld/extension/CheckstyleOperationTest.java
@@ -16,10 +16,12 @@
 
 package rife.bld.extension;
 
+import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.Test;
 import rife.bld.BaseProject;
 import rife.bld.Project;
 import rife.bld.WebProject;
+import rife.bld.extension.checkstyle.OutputFormat;
 import rife.bld.operations.exceptions.ExitStatusException;
 
 import java.io.File;
@@ -27,21 +29,38 @@ import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Paths;
 import java.util.List;
+import java.util.logging.ConsoleHandler;
+import java.util.logging.Level;
+import java.util.logging.Logger;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatCode;
 
 
 class CheckstyleOperationTest {
+    public static final String SRC_MAIN_JAVA = "src/main/java";
+    public static final String SRC_TEST_JAVA = "src/test/java";
     private static final String ADD = "add";
     private static final String BAR = "bar";
     private static final String FOO = "foo";
     private static final String REMOVE = "remove";
 
+    @BeforeAll
+    static void beforeAll() {
+        var level = Level.ALL;
+        var logger = Logger.getLogger("rife.bld.extension");
+        var consoleHandler = new ConsoleHandler();
+        consoleHandler.setLevel(level);
+        logger.addHandler(consoleHandler);
+        logger.setLevel(level);
+        logger.setUseParentHandlers(false);
+    }
+
+
     @Test
     void branchMatchingXpath() {
         var op = new CheckstyleOperation().fromProject(new Project()).branchMatchingXpath(FOO);
-        assertThat(op.options.get("-b")).isEqualTo(FOO);
+        assertThat(op.options().get("-b")).isEqualTo(FOO);
     }
 
     @Test
@@ -53,16 +72,16 @@ class CheckstyleOperationTest {
         var params = new CheckstyleOperation()
                 .fromProject(new Project())
                 .branchMatchingXpath("xpath")
-                .configurationFile("config")
                 .debug(true)
-                .exclude("path")
+                .configurationFile(new File("config"))
+                .exclude(SRC_MAIN_JAVA)
                 .excludeRegex("regex")
                 .executeIgnoredModules(true)
-                .format(CheckstyleFormatOption.XML)
+                .format(OutputFormat.XML)
                 .generateXpathSuppression(true)
                 .javadocTree(true)
-                .outputPath("optionPath")
-                .propertiesFile("properties")
+                .outputPath(new File("optionPath"))
+                .propertiesFile(new File("properties"))
                 .suppressionLineColumnNumber("12")
                 .tabWith(1)
                 .tree(true)
@@ -85,25 +104,33 @@ class CheckstyleOperationTest {
     @Test
     void configurationFile() {
         var op = new CheckstyleOperation().fromProject(new Project()).configurationFile(FOO);
-        assertThat(op.options.get("-c")).isEqualTo(FOO);
+        assertThat(op.options().get("-c")).isEqualTo(FOO);
     }
 
     @Test
     void debug() {
         var op = new CheckstyleOperation().fromProject(new Project()).debug(true);
-        assertThat(op.options.containsKey("-d")).as(ADD).isTrue();
+        assertThat(op.options().containsKey("-d")).as(ADD).isTrue();
         op = op.debug(false);
-        assertThat(op.options.containsKey("-d")).as(REMOVE).isFalse();
+        assertThat(op.options().containsKey("-d")).as(REMOVE).isFalse();
     }
 
     @Test
     void exclude() {
-        var op = new CheckstyleOperation().fromProject(new Project()).exclude(FOO, BAR);
+        var foo = new File(SRC_MAIN_JAVA);
+        var bar = new File(SRC_TEST_JAVA);
+        var op = new CheckstyleOperation().fromProject(new Project()).exclude(SRC_MAIN_JAVA, SRC_TEST_JAVA);
         var e = "-e ";
-        assertThat(op.executeConstructProcessCommandList()).contains(e + FOO, e + BAR);
+        assertThat(op.executeConstructProcessCommandList()).as("strings")
+                .contains(e + foo.getAbsolutePath()).contains(e + bar.getAbsolutePath());
 
-        op = new CheckstyleOperation().fromProject(new Project()).exclude(List.of(FOO, BAR));
-        assertThat(op.executeConstructProcessCommandList()).as("as list").contains(e + FOO, e + BAR);
+        op = new CheckstyleOperation().fromProject(new Project()).exclude(foo, bar);
+        assertThat(op.executeConstructProcessCommandList()).as("files")
+                .contains(e + foo.getAbsolutePath()).contains(e + bar.getAbsolutePath());
+
+        op = new CheckstyleOperation().fromProject(new Project()).exclude(List.of(foo, bar));
+        assertThat(op.executeConstructProcessCommandList()).as("list")
+                .contains(e + foo.getAbsolutePath()).contains(e + bar.getAbsolutePath());
     }
 
     @Test
@@ -122,13 +149,19 @@ class CheckstyleOperationTest {
         tmpFile.deleteOnExit();
         var op = new CheckstyleOperation()
                 .fromProject(new WebProject())
-                .sourceDir("src/main/java", "src/test/java")
+                .sourceDir(SRC_MAIN_JAVA, SRC_TEST_JAVA)
                 .configurationFile("src/test/resources/google_checks.xml")
                 .outputPath(tmpFile.getAbsolutePath());
         op.execute();
         assertThat(tmpFile).exists();
     }
 
+    @Test
+    void executeNoProject() {
+        var op = new CheckstyleOperation();
+        assertThatCode(op::execute).isInstanceOf(ExitStatusException.class);
+    }
+
     @Test
     void executeConstructProcessCommandList() {
         var op = new CheckstyleOperation().fromProject(new BaseProject())
@@ -137,7 +170,7 @@ class CheckstyleOperationTest {
                 .propertiesFile("config/checkstyle.properties")
                 .debug(true)
                 .executeIgnoredModules(true)
-                .sourceDir("src/main/java", "src/test/java");
+                .sourceDir(SRC_MAIN_JAVA, SRC_TEST_JAVA);
         assertThat(String.join(" ", op.executeConstructProcessCommandList()))
                 .startsWith("java -cp ")
                 .endsWith(
@@ -146,15 +179,16 @@ class CheckstyleOperationTest {
                                 "-b xpath " +
                                 "-c config/checkstyle.xml " +
                                 "-d -E " +
-                                "src/main/java src/test/java");
+                                new File(SRC_MAIN_JAVA).getAbsolutePath() + " " +
+                                new File(SRC_TEST_JAVA).getAbsolutePath());
     }
 
     @Test
     void executeIgnoredModules() {
         var op = new CheckstyleOperation().fromProject(new Project()).executeIgnoredModules(true);
-        assertThat(op.options.containsKey("-E")).as(ADD).isTrue();
+        assertThat(op.options().containsKey("-E")).as(ADD).isTrue();
         op = op.executeIgnoredModules(false);
-        assertThat(op.options.containsKey("-E")).as(REMOVE).isFalse();
+        assertThat(op.options().containsKey("-E")).as(REMOVE).isFalse();
     }
 
     @Test
@@ -163,7 +197,7 @@ class CheckstyleOperationTest {
         tmpFile.deleteOnExit();
         var op = new CheckstyleOperation()
                 .fromProject(new WebProject())
-                .sourceDir(List.of("src/main/java", "src/test/java"))
+                .sourceDir(SRC_MAIN_JAVA, SRC_TEST_JAVA)
                 .configurationFile("src/test/resources/sun_checks.xml")
                 .outputPath(tmpFile.getAbsolutePath());
         assertThatCode(op::execute).isInstanceOf(ExitStatusException.class);
@@ -172,79 +206,88 @@ class CheckstyleOperationTest {
 
     @Test
     void format() {
-        var op = new CheckstyleOperation().fromProject(new Project()).format(CheckstyleFormatOption.XML);
-        assertThat(op.options.get("-f")).isEqualTo("xml");
+        var op = new CheckstyleOperation().fromProject(new Project()).format(OutputFormat.XML);
+        assertThat(op.options().get("-f")).isEqualTo("xml");
     }
 
     @Test
     void generateXpathSuppression() {
         var op = new CheckstyleOperation().fromProject(new Project()).generateXpathSuppression(true);
-        assertThat(op.options.containsKey("-g")).as(ADD).isTrue();
+        assertThat(op.options().containsKey("-g")).as(ADD).isTrue();
         op = op.generateXpathSuppression(false);
-        assertThat(op.options.containsKey("-g")).as(REMOVE).isFalse();
+        assertThat(op.options().containsKey("-g")).as(REMOVE).isFalse();
     }
 
     @Test
     void javadocTree() {
         var op = new CheckstyleOperation().fromProject(new Project()).javadocTree(true);
-        assertThat(op.options.containsKey("-j")).as(ADD).isTrue();
+        assertThat(op.options().containsKey("-j")).as(ADD).isTrue();
         op = op.javadocTree(false);
-        assertThat(op.options.containsKey("-j")).as(REMOVE).isFalse();
+        assertThat(op.options().containsKey("-j")).as(REMOVE).isFalse();
     }
 
     @Test
     void outputPath() {
         var op = new CheckstyleOperation().fromProject(new Project()).outputPath(FOO);
-        assertThat(op.options.get("-o")).isEqualTo(FOO);
+        assertThat(op.options().get("-o")).isEqualTo(FOO);
     }
 
     @Test
     void propertiesFile() {
         var op = new CheckstyleOperation().fromProject(new Project()).propertiesFile(FOO);
-        assertThat(op.options.get("-p")).isEqualTo(FOO);
+        assertThat(op.options().get("-p")).isEqualTo(FOO);
     }
 
     @Test
     void sourceDir() {
+        var foo = new File(FOO);
+        var bar = new File(BAR);
+
         var op = new CheckstyleOperation().fromProject(new Project()).sourceDir(FOO);
-        assertThat(op.sourceDirs).contains(FOO);
-        op = op.sourceDir(FOO, BAR);
-        assertThat(op.sourceDirs).as("foo, bar").hasSize(2).contains(FOO).contains(BAR);
+        assertThat(op.sourceDir()).contains(foo);
+
+        op = op.sourceDir(foo, bar);
+        assertThat(op.sourceDir()).as("foo, bar").hasSize(2)
+                .contains(foo).contains(bar);
+
+        op = op.sourceDir(List.of(foo, bar));
+        assertThat(op.sourceDir()).as("List.of(foo, bar)").hasSize(2)
+                .contains(foo).contains(bar);
     }
 
     @Test
     void suppressionLineColumnNumber() {
         var op = new CheckstyleOperation().fromProject(new Project()).suppressionLineColumnNumber(FOO + ':' + BAR);
-        assertThat(op.options.get("-s")).isEqualTo(FOO + ':' + BAR);
+        assertThat(op.options().get("-s")).isEqualTo(FOO + ':' + BAR);
     }
 
     @Test
     void tabWith() {
         var op = new CheckstyleOperation().fromProject(new Project()).tabWith(9);
-        assertThat(op.options.get("-w")).isEqualTo("9");
+        assertThat(op.options().get("-w")).isEqualTo("9");
     }
 
     @Test
     void tree() {
         var op = new CheckstyleOperation().fromProject(new Project()).tree(true);
-        assertThat(op.options.containsKey("-t")).as(ADD).isTrue();
+        assertThat(op.options().containsKey("-t")).as(ADD).isTrue();
         op = op.tree(false);
-        assertThat(op.options.containsKey("-t")).as(REMOVE).isFalse();
+        assertThat(op.options().containsKey("-t")).as(REMOVE).isFalse();
     }
 
     @Test
     void treeWithComments() {
         var op = new CheckstyleOperation().fromProject(new Project()).treeWithComments(true);
-        assertThat(op.options.containsKey("-T")).as(ADD).isTrue();
+        assertThat(op.options().containsKey("-T")).as(ADD).isTrue();
         op = op.treeWithComments(false);
-        assertThat(op.options.containsKey("-T")).as(REMOVE).isFalse();
+        assertThat(op.options().containsKey("-T")).as(REMOVE).isFalse();
     }
 
     @Test
     void treeWithJavadoc() {
         var op = new CheckstyleOperation().fromProject(new Project()).treeWithJavadoc(true);
-        assertThat(op.options.containsKey("-J")).as(ADD).isTrue();
+        assertThat(op.options().containsKey("-J")).as(ADD).isTrue();
         op = op.treeWithJavadoc(false);
-        assertThat(op.options.containsKey("-J")).as(REMOVE).isFalse();
+        assertThat(op.options().containsKey("-J")).as(REMOVE).isFalse();
     }
 }