Merge pull request #2208 from jplag/feature/wsl-networking-fix

Ensure that IPv4 network stack is preferred.

cli/src/main/java/de/jplag/cli/CLI.java

@@ -203,6 +203,10 @@ private String getWritableFileName() throws CliException {
     }
 
     public static void main(String[] args) {
+        // This needs to be executed before any other code, as it changes the default behavior of the JVM for network
+        // connections.
+        System.setProperty("java.net.preferIPv4Stack", "true");
+
         CLI cli = new CLI(args);
         if (cli.executeCliAndHandleErrors()) {
             System.exit(1);

cli/src/main/java/de/jplag/cli/server/ReportViewer.java

@@ -64,8 +64,6 @@ public int start() throws IOException {
             throw new IllegalStateException("Server already started");
         }
 
-        System.setProperty("java.net.preferIPv4Stack", "true");
-
         int currentPort = this.port;
         int remainingLookups = MAX_PORT_LOOKUPS;
         BindException lastException = new BindException("Could not create server. Probably due to no free port found.");