Update to Java 21 (#2890)

We will start 2025 with an update to latest LTS version Java 21, released on 19th September 2023 (https://en.wikipedia.org/wiki/Java_version_history#Release_table).

This commit only covers the basic migration to Java 21. Features that have been deprecated are not yet fixed and will appear in your (Eclipse) IDE, like
- `The constructor Locale(String, String) is deprecated since version 19`
- `The constructor URL(String) is deprecated since version 20`
- `The method exec(String) from the type Runtime is deprecated since version 18`
These will be fixed in follow-up PRs.

If you happen to receive a Eclipse warning `bnd has ‘21’ while Eclipse has ‘17’` please update your IDE settings: https://bnd.bndtools.org/chapters/910-warnings.html

We recommend using JDK 21 from the Eclipse Temurin project: https://adoptium.net/de/temurin/releases/. See updated deployment guides for details:
- https://openems.github.io/openems.io/openems/latest/edge/deploy.html#_prepare_operating_system_environment
- https://openems.github.io/openems.io/openems/latest/backend/deploy.html

If you need a compatible Java 21 JRE for ARM32, we are providing a prebuilt Debian package here: https://community.openems.io/t/java-21-jdk-for-arm32/3253

cnf/build.bnd

@@ -75,5 +75,5 @@ testpath: \
 	Edge_Timedata;member=${filter;${p};io\.openems\.edge\.timedata\..*},\
 	Edge_TimeOfUseTariff;member=${filter;${p};io\.openems\.edge\.timeofusetariff\..*},\
 
-javac.source: 17
-javac.target: 17
+javac.source: 21
+javac.target: 21

doc/modules/ROOT/pages/backend/deploy.adoc

@@ -16,6 +16,14 @@ This chapter explains how OpenEMS Backend can be deployed on a Debian Linux serv
 
 NOTE: It is recommended to run every service on a server with limited permissions. This example runs OpenEMS Backend with user "root" which is a bad idea for a production server!  
 
+==== Check JAVA version
+
+Ensure that a JRE version 21 or later is installed. We recommend using `temurin-21-jre`
+
+For detailed installation instructions, visit https://adoptium.net/de/installation/linux/[Adoptium Installation Guide].
+
+NOTE: If you are using an *ARM32* device, download https://openems.io/download/temurin-21-jre-armhf_21.0.6+2.deb[temurin-21-jre-armhf_21.0.6+2.deb] directly from OpenEMS.
+
 ==== Create an application directory
 
 Create the directory */opt/openems-backend*. This is going to be the place, where we put the JAR file.

doc/modules/ROOT/pages/contribute/coding-guidelines.adoc

@@ -25,7 +25,7 @@
 * Use precise naming for methods/functions
 * Use narrow scopes for variables; avoid class variables
 * Split code in Interface, Implementation(..Impl) and Config files
-* Use modern Java 17 syntax (e.g. 'var' keyword, streams, etc.)
+* Use modern Java 21 syntax (e.g. 'var' keyword, streams, etc.)
 * Add readme.adoc to a new bundle
 * Review data in bnd.bnd file
 * Format all files via Eclipse Autoformat, organize Imports, apply Checkstyle suggestions (see below)

doc/modules/ROOT/pages/edge/deploy.adoc

@@ -58,6 +58,14 @@ image::deploy-winscp.png[Start WinSCP from KiTTY]
 
 === Prepare operating system environment
 
+==== Check JAVA version
+
+Ensure that a JRE version 21 or later is installed. We recommend using `temurin-21-jre`
+
+For detailed installation instructions, visit https://adoptium.net/de/installation/linux/[Adoptium Installation Guide].
+
+NOTE: If you are using an *ARM32* device, download https://openems.io/download/temurin-21-jre-armhf_21.0.6+2.deb[temurin-21-jre-armhf_21.0.6+2.deb] directly from OpenEMS.
+
 ==== Create an application directory
 
 Create the directory */usr/lib/openems*. This is going to be the place, where we put the JAR file.

doc/modules/ROOT/pages/gettingstarted.adoc

@@ -41,7 +41,7 @@ NOTE: OpenEMS uses the **git** version control system via the popular GitHub pla
 NOTE: Eclipse IDE is the recommended development environment for newcomers to OpenEMS. If you are more familiar with IntelliJ IDEA, feel free to use it. Follow xref:intellij.adoc[this guide].
 
 . Prepare Eclipse IDE
-.. Download Java Development Kit (JDK) 17 and install it. We recommend the https://adoptium.net/de/temurin/releases/?version=17[OpenJDK Temurin builds by the Adoptium project]
+.. Download Java Development Kit (JDK) 21 and install it. We recommend the https://adoptium.net/de/temurin/releases/?version=21[OpenJDK Temurin builds by the Adoptium project]
 .. Download https://www.eclipse.org/downloads/[Eclipse for Java icon:external-link[]], install and start it
 .. On first start you will get asked to create a workspace.
 Select your source code directory (`C:\Users\your.user\git\openems` in our example) and press btn:[Launch].
@@ -53,15 +53,15 @@ image::eclipse-workspace.png[Creating a workspace in Eclipse IDE]
 +
 Menu: btn:[Help] → btn:[Eclipse Marketplace...] → btn:[Find:] → enter btn:[Bndtools] → press btn:[Install]
 
-.. Configure Eclipse IDE to use JDK 17.
+.. Configure Eclipse IDE to use JDK 21.
 +
 - In the Menu select btn:[Windows] → btn:[Preferences]
 - Select btn:[Java] - btn:[Installed JREs] in the navigation tree
 - Press the btn:[Add...] button
 - Keep btn:[Standard VM] selected and press btn:[Next >]
-- Press the btn:[Directory...] button and select the folder of the installed JDK (e.g. `C:\Program Files\Eclipse Adoptium\jdk-17.0.7.7-hotspot`)
+- Press the btn:[Directory...] button and select the folder of the installed JDK (e.g. `C:\Program Files\Eclipse Adoptium\jdk-21.0.3.9-hotspot`)
 - Press the btn:[Finish] button
-- Back in the Preferences window, tick the newly added JDK 17 and press btn:[Apply and Close]
+- Back in the Preferences window, tick the newly added JDK 21 and press btn:[Apply and Close]
 +
 .Creating a workspace in Eclipse IDE
 image::eclipse-select-jdk.png[Set the Java Development Kit in Eclipse IDE]

gradle.properties

@@ -1,5 +1,5 @@
 java_source=21
-java_target=17
+java_target=21
 
 bnd_version=7.1.0
 bnd_snapshots=https://bndtools.jfrog.io/bndtools/libs-snapshot-local

io.openems.backend.alerting/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.backend.application/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.backend.application/BackendApp.bndrun

@@ -1,5 +1,5 @@
 -runfw: org.apache.felix.framework;version='[7.0.5,7.0.5]'
--runee: JavaSE-17
+-runee: JavaSE-21
 -runprovidedcapabilities: ${native_capability}
 
 -resolve.effective: active

io.openems.backend.b2brest/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.backend.b2bwebsocket/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.backend.common/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.backend.core/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.backend.edgewebsocket/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.backend.metadata.dummy/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.backend.metadata.file/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.backend.metadata.odoo/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.backend.timedata.aggregatedinflux/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.backend.timedata.dummy/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.backend.timedata.influx/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.backend.timedata.timescaledb/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.backend.uiwebsocket/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.common/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.edge.application/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.edge.application/EdgeApp.bndrun

@@ -1,5 +1,5 @@
 -runfw: org.apache.felix.framework;version='[7.0.5,7.0.5]'
--runee: JavaSE-17
+-runee: JavaSE-21
 -runprovidedcapabilities: ${native_capability}
 
 -resolve.effective: active

io.openems.edge.battery.api/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.edge.battery.bmw/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.edge.battery.bydcommercial/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.edge.battery.fenecon.commercial/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.edge.battery.fenecon.home/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.edge.battery.soltaro/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.edge.batteryinverter.api/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.edge.batteryinverter.kaco.blueplanetgridsave/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.edge.batteryinverter.refu88k/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>

io.openems.edge.batteryinverter.sinexcel/.classpath

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="con" path="aQute.bnd.classpath.container"/>
-	<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="src" output="bin" path="src"/>
 	<classpathentry kind="src" output="bin_test" path="test">
 		<attributes>