diff --git a/com.vogella.swt.widgets/.classpath b/com.vogella.swt.widgets/.classpath
index 81fe078c..375961e4 100644
--- a/com.vogella.swt.widgets/.classpath
+++ b/com.vogella.swt.widgets/.classpath
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
-	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-17"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-21"/>
 	<classpathentry kind="con" path="org.eclipse.pde.core.requiredPlugins"/>
 	<classpathentry kind="src" path="src"/>
 	<classpathentry kind="output" path="bin"/>
diff --git a/com.vogella.swt.widgets/.settings/org.eclipse.jdt.core.prefs b/com.vogella.swt.widgets/.settings/org.eclipse.jdt.core.prefs
index 62ef3488..23fa13b1 100644
--- a/com.vogella.swt.widgets/.settings/org.eclipse.jdt.core.prefs
+++ b/com.vogella.swt.widgets/.settings/org.eclipse.jdt.core.prefs
@@ -1,9 +1,9 @@
 eclipse.preferences.version=1
-org.eclipse.jdt.core.compiler.codegen.targetPlatform=17
-org.eclipse.jdt.core.compiler.compliance=17
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=21
+org.eclipse.jdt.core.compiler.compliance=21
 org.eclipse.jdt.core.compiler.problem.assertIdentifier=error
 org.eclipse.jdt.core.compiler.problem.enablePreviewFeatures=disabled
 org.eclipse.jdt.core.compiler.problem.enumIdentifier=error
 org.eclipse.jdt.core.compiler.problem.reportPreviewFeatures=warning
 org.eclipse.jdt.core.compiler.release=enabled
-org.eclipse.jdt.core.compiler.source=17
+org.eclipse.jdt.core.compiler.source=21
diff --git a/com.vogella.swt.widgets/META-INF/MANIFEST.MF b/com.vogella.swt.widgets/META-INF/MANIFEST.MF
index bd2be212..568cc45d 100644
--- a/com.vogella.swt.widgets/META-INF/MANIFEST.MF
+++ b/com.vogella.swt.widgets/META-INF/MANIFEST.MF
@@ -5,7 +5,7 @@ Bundle-SymbolicName: com.vogella.swt.widgets
 Bundle-Version: 1.0.0.qualifier
 Bundle-Vendor: VOGELLA
 Automatic-Module-Name: com.vogella.swt.widgets
-Bundle-RequiredExecutionEnvironment: JavaSE-17
+Bundle-RequiredExecutionEnvironment: JavaSE-21
 Require-Bundle: org.eclipse.core.runtime;bundle-version="3.20.100",
  org.eclipse.jface;bundle-version="3.22.100"
 Export-Package: com.vogella.swt.widgets