Add Java System logger to the jsch instance

Shift log level to less serious level
 - Jsch issues a lot of INFO messages which are rather DEBUG level and warnings, which are rather info level
Signed-off-by:Ondro Mihalyi <mihalyi@omnifish.ee>

nucleus/admin/template/src/main/resources/config/logging.properties

@@ -139,6 +139,7 @@ jakarta.enterprise.system.core.naming.level=INFO
 jakarta.enterprise.system.core.security.level=INFO
 jakarta.enterprise.system.core.security.web.level=INFO
 jakarta.enterprise.system.core.selfmanagement.level=INFO
+jakarta.enterprise.system.core.ssh.level=INFO
 jakarta.enterprise.system.core.transaction.level=INFO
 jakarta.enterprise.system.jmx.level=INFO
 jakarta.enterprise.system.security.ssl.level=INFO

nucleus/cluster/ssh/src/main/java/org/glassfish/cluster/ssh/launcher/JavaSystemJschLogger.java

@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2023 Contributors to the Eclipse Foundation
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0, which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * This Source Code may also be made available under the following Secondary
+ * Licenses when the conditions for such availability set forth in the
+ * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
+ * version 2 with the GNU Classpath Exception, which is available at
+ * https://www.gnu.org/software/classpath/license.html.
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
+ */
+package org.glassfish.cluster.ssh.launcher;
+
+import com.jcraft.jsch.JSch;
+import java.lang.System.Logger;
+import java.lang.System.Logger.Level;
+
+public class JavaSystemJschLogger implements com.jcraft.jsch.Logger {
+
+    private final Logger logger;
+
+    public JavaSystemJschLogger() {
+        this.logger = System.getLogger(JSch.class.getName());
+    }
+
+    public JavaSystemJschLogger(String loggerName) {
+        this.logger = System.getLogger(loggerName);
+    }
+
+    @Override
+    public boolean isEnabled(int jschLevel) {
+        return logger.isLoggable(getSystemLoggerLevel(jschLevel));
+    }
+
+    @Override
+    public void log(int jschLevel, String message) {
+        logger.log(getSystemLoggerLevel(jschLevel), message);
+    }
+
+    @Override
+    public void log(int jschLevel, String message, Throwable cause) {
+        if (cause != null) {
+            logger.log(getSystemLoggerLevel(jschLevel), message, cause);
+        } else {
+            logger.log(getSystemLoggerLevel(jschLevel), message);
+        }
+    }
+
+    static Level getSystemLoggerLevel(int jschLevel) {
+        switch (jschLevel) {
+            case DEBUG:
+                return Level.TRACE;
+            case INFO:
+                return Level.DEBUG;
+            case WARN:
+                return Level.INFO;
+            case ERROR:
+                return Level.WARNING;
+            case FATAL:
+                return Level.ERROR;
+            default:
+                return Level.TRACE;
+        }
+    }
+
+}

nucleus/cluster/ssh/src/main/java/org/glassfish/cluster/ssh/launcher/SSHLauncher.java

@@ -1,4 +1,5 @@
 /*
+ * Copyright (c) 2023 Contributors to the Eclipse Foundation
  * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
  *
  * This program and the accompanying materials are made available under the
@@ -191,8 +192,7 @@ public void init(String userName, String host, int port, String password, String
     private void openConnection() throws JSchException {
         assert session == null;
         JSch jsch = new JSch();
-        // TODO: Logger?
-        // jsch.setLogger(logger);
+        jsch.setLogger(new JavaSystemJschLogger(logger != null ? logger.getName() + ".ssh" : JSch.class.getName()));
 
         // Client Auth
         String message = "";