diff --git a/src/test/java/lambdas/FileFilterTest.java b/src/test/java/lambdas/FileFilterTest.java
index 489b4dc..76a6c88 100644
--- a/src/test/java/lambdas/FileFilterTest.java
+++ b/src/test/java/lambdas/FileFilterTest.java
@@ -4,6 +4,7 @@
 
 import java.io.File;
 import java.io.FileFilter;
+import java.util.List;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
@@ -17,6 +18,7 @@ public void testListFiles() {
         assertEquals(22, files.length);
     }
 
+    @SuppressWarnings({"Convert2Lambda", "Anonymous2MethodRef"})
     @Test
     void listDirectories_anonInnerClass() {
         File[] directories = root.listFiles(new FileFilter() {
@@ -29,6 +31,7 @@ public boolean accept(File pathname) {
         assertEquals(14, directories.length);
     }
 
+    @SuppressWarnings("Convert2MethodRef")
     @Test
     void listDirectories_expression_lambda() {
         File[] directories = root.listFiles(file -> file.isDirectory());
@@ -36,5 +39,59 @@ void listDirectories_expression_lambda() {
         assertEquals(14, directories.length);
     }
 
+    @SuppressWarnings("Convert2MethodRef")
+    @Test
+    void listDirectories_lambda_variable() {
+        FileFilter fileFilter = file -> file.isDirectory();
+        File[] directories = root.listFiles(fileFilter);
+        assert directories != null;
+        assertEquals(14, directories.length);
+    }
+
+    @SuppressWarnings({"Convert2MethodRef", "CodeBlock2Expr"})
+    @Test
+    void listDirectories_block_lambda() {
+        File[] directories = root.listFiles(file -> {
+            return file.isDirectory();
+        });
+        assert directories != null;
+        assertEquals(14, directories.length);
+    }
+
+    @Test
+    void listDirectories_method_reference() {
+        File[] directories = root.listFiles(File::isDirectory);
+        assert directories != null;
+        assertEquals(14, directories.length);
+    }
+
+    @Test
+    void listJavaSrcFiles_fileFilter() {
+        File[] javaFiles = root.listFiles(file -> file.getName().endsWith(".java"));
+        assert javaFiles != null;
+        assertEquals(8, javaFiles.length);
+    }
+
+    @Test
+    void listJavaSrcFiles_fileNameFilter() {
+        File[] javaFiles = root.listFiles((dir, name) -> name.endsWith(".java"));
+        assert javaFiles != null;
+        assertEquals(8, javaFiles.length);
+    }
+
+    @Test
+    void forEach_on_a_list() {
+        List<String> strings = List.of("this", "is", "a", "list");
+        // Java 5+
+        for (String string : strings) {
+            System.out.println(string);
+        }
+
+        // Java 8+
+        strings.forEach(System.out::println);
+
+        // Parallel stream
+        strings.parallelStream().forEach(System.out::println);
+    }
 
 }