Updates Java to 21 and license headers

pom.xml

@@ -32,8 +32,8 @@
 	</licenses>
 
 	<properties>
-		<maven.compiler.source>11</maven.compiler.source>
-		<maven.compiler.target>11</maven.compiler.target>
+		<maven.compiler.source>21</maven.compiler.source>
+		<maven.compiler.target>21</maven.compiler.target>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
 

src/main/java/es/uvigo/esei/dai/sockets/example1/HelloWorldClient.java

@@ -2,7 +2,7 @@
  * #%L
  * Ejemplos de DAI - Sockets
  * %%
- * Copyright (C) 2014 - 2023 Miguel Reboiro Jato
+ * Copyright (C) 2014 - 2026 Miguel Reboiro Jato
  * %%
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as

src/main/java/es/uvigo/esei/dai/sockets/example1/HelloWorldServer.java

@@ -2,7 +2,7 @@
  * #%L
  * Ejemplos de DAI - Sockets
  * %%
- * Copyright (C) 2014 - 2023 Miguel Reboiro Jato
+ * Copyright (C) 2014 - 2026 Miguel Reboiro Jato
  * %%
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as

src/main/java/es/uvigo/esei/dai/sockets/example2/HelloWorldReceiver.java

@@ -2,7 +2,7 @@
  * #%L
  * Ejemplos de DAI - Sockets
  * %%
- * Copyright (C) 2014 - 2023 Miguel Reboiro Jato
+ * Copyright (C) 2014 - 2026 Miguel Reboiro Jato
  * %%
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as

src/main/java/es/uvigo/esei/dai/sockets/example2/HelloWorldSender.java

@@ -2,7 +2,7 @@
  * #%L
  * Ejemplos de DAI - Sockets
  * %%
- * Copyright (C) 2014 - 2023 Miguel Reboiro Jato
+ * Copyright (C) 2014 - 2026 Miguel Reboiro Jato
  * %%
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as

src/main/java/es/uvigo/esei/dai/sockets/example3/EchoClient.java

@@ -2,7 +2,7 @@
  * #%L
  * Ejemplos de DAI - Sockets
  * %%
- * Copyright (C) 2014 - 2023 Miguel Reboiro Jato
+ * Copyright (C) 2014 - 2026 Miguel Reboiro Jato
  * %%
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as

src/main/java/es/uvigo/esei/dai/sockets/example3/EchoReceiver.java

@@ -2,7 +2,7 @@
  * #%L
  * Ejemplos de DAI - Sockets
  * %%
- * Copyright (C) 2014 - 2023 Miguel Reboiro Jato
+ * Copyright (C) 2014 - 2026 Miguel Reboiro Jato
  * %%
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as

src/main/java/es/uvigo/esei/dai/sockets/example3/EchoSender.java

@@ -2,7 +2,7 @@
  * #%L
  * Ejemplos de DAI - Sockets
  * %%
- * Copyright (C) 2014 - 2023 Miguel Reboiro Jato
+ * Copyright (C) 2014 - 2026 Miguel Reboiro Jato
  * %%
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as

src/main/java/es/uvigo/esei/dai/sockets/example3/EchoServer.java

@@ -2,7 +2,7 @@
  * #%L
  * Ejemplos de DAI - Sockets
  * %%
- * Copyright (C) 2014 - 2023 Miguel Reboiro Jato
+ * Copyright (C) 2014 - 2026 Miguel Reboiro Jato
  * %%
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as

src/main/java/es/uvigo/esei/dai/sockets/example4/Message.java

@@ -2,7 +2,7 @@
  * #%L
  * Ejemplos de DAI - Sockets
  * %%
- * Copyright (C) 2014 - 2023 Miguel Reboiro Jato
+ * Copyright (C) 2014 - 2026 Miguel Reboiro Jato
  * %%
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as

src/main/java/es/uvigo/esei/dai/sockets/example4/MessageReceiver.java

@@ -2,7 +2,7 @@
  * #%L
  * Ejemplos de DAI - Sockets
  * %%
- * Copyright (C) 2014 - 2023 Miguel Reboiro Jato
+ * Copyright (C) 2014 - 2026 Miguel Reboiro Jato
  * %%
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as

src/main/java/es/uvigo/esei/dai/sockets/example4/MessageSender.java

@@ -2,7 +2,7 @@
  * #%L
  * Ejemplos de DAI - Sockets
  * %%
- * Copyright (C) 2014 - 2023 Miguel Reboiro Jato
+ * Copyright (C) 2014 - 2026 Miguel Reboiro Jato
  * %%
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as

src/main/java/es/uvigo/esei/dai/sockets/example5/ESEIHomeDownload.java

@@ -2,7 +2,7 @@
  * #%L
  * Ejemplos de DAI - Sockets
  * %%
- * Copyright (C) 2014 - 2023 Miguel Reboiro Jato
+ * Copyright (C) 2014 - 2026 Miguel Reboiro Jato
  * %%
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as