Added few docs

CHANGES.md

@@ -1,4 +1,7 @@
-Next version
+next version
+----
+
+0.21 - 2023 Apr 19
 ----
 
 - Added `--force-hostname` option to overriden endpoint hostname on RMI stub with JMX connection hostname (useful for NAT and containers)

sjk-core/docs/MPRX.md

@@ -1,20 +1,31 @@
 `mprx` command
 ==============
 
-`mprx` command opens JMX port on target JVM (specified by PID) suitable for remote connections from normal JMX
-based tools, such as JVisualVM or Java Mission Control.
+`mprx` command opens JMX port on target JVM (specified by PID or socket address) suitable for remote 
+connections from normal JMX based tools, such as JVisualVM or Java Mission Control.
+
+It could be also used to solve problem with improprly setup remote JMX end point using `--force-address` option.
 
 SJK acts as proxy in this case and socket would be closed after termination of SJK process.
 
 Usage
 -----
 
-	> java -jar skj.jar --help mprx
+	> java -jar sjk.jar mprx --help
 	JMX proxy - expose target process' MBeans for remote access
 	Usage: mprx [options]
 	  Options:
 			--commands
 		   
+		   Default: false
+			--force-address
+		   Override hostname:port for JMX RMI stub, default false
+		   Default: false
+			--force-hostname
+		   Override hostname for JMX RMI stub, default false
+		   Default: false
+			--force-port
+		   Override port for JMX RMI stub, default false
 		   Default: false
 			--help
 		   
@@ -33,3 +44,25 @@ Usage
 	  * -b
 		   Bind address - HOST:PORT
 
+Example of process side proxy
+-----------------------------
+
+You can run `mprx` command on the same host as target process. While JMX agent could be started in runtime using `jcmd` from JDK,
+sometimes JMX remote connectivy requires overriding `java.rmi.server.hostname` JVM system propery which cannot be done without
+restart.
+
+With `mprx` you can run JMX end point as separate process with full control overconfiguration.
+
+Example of client side proxy
+----------------------------
+
+Even if remote JMX port is open and exposed, JMX connetion from tools such as VisualVM and MissionControl may not pass through.
+Issue, usually, is in JMX handshake providing unroutable network address for data connection. You can use `mxping` to verify that.
+
+SJK has `--force-address` to solve that kind of issue. If you want to use other tools, e.g. VisualVM, you can proxy JMX though SJK.
+
+	> java -jar sjk.jar mprx -s server.local:7777 --force-address -b 127.0.0.1:7777
+
+Assuming server.local:7777 is listening JMX connections, you can not point VisualVM to 127.0.0.1:7777 and access remote MBean tree.
+
+This also can be usefull if you are using any kind of port forwarding for remote access.

sjk-core/docs/MXPING.md

@@ -0,0 +1,63 @@
+`mxping` command
+==============
+
+`mxping` command can be used to troubleshoot JMX connectivity. It accepts eigther process PID 
+or JMX socket address. In both cases process is throughfully logged helping problem cause identification.
+
+In case of remote connection in sophysticated network topology, connection address received from RMI registry
+on first step of JMX handshake may be incrorrect. `--force-address` option would be useful here to ignore address
+from RMI stub.
+
+Usage
+-----
+
+	> java -jar sjk.jar mxping --help
+	[MXPING] Verify JMX connection to target JVM
+	Usage: mxping [options]
+	  Options:
+			--commands
+		   
+		   Default: false
+			--force-address
+		   Override hostname:port for JMX RMI stub, default false
+		   Default: false
+			--force-hostname
+		   Override hostname for JMX RMI stub, default false
+		   Default: false
+			--force-port
+		   Override port for JMX RMI stub, default false
+		   Default: false
+			--help
+		   
+		   Default: false
+			--password
+		   Password for JMX authentication (only for socket connection)
+		-p, --pid
+		   JVM process PID
+		-s, --socket
+		   Socket address for JMX port (host:port)
+			--user
+		   User for JMX authentication (only for socket connection)
+		-X, --verbose
+		   Enable detailed diagnostics
+		   Default: false
+
+Output example
+--------------
+
+	> java -jar sjk.jar mxping -s 127.0.0.1:34000
+	SJK is running on: OpenJDK 64-Bit Server VM 25.275-b01 (BellSoft)
+	Java home: C:\WarZone\WarPath\Java\jdk1.8.0_275+1_bellsoft_x64\jre
+	Try to connect via TLS
+	Establishing connection to 127.0.0.1:34000
+	Failed to connect using TLS: java.rmi.ConnectIOException: error during JRMP connection establishment; nested exception is: 
+		javax.net.ssl.SSLHandshakeException: Remote host terminated the handshake
+	Try to use plain socket
+	Establishing connection to 127.0.0.1:34000
+	Establishing connection to 192.168.100.1:34000
+	Remote VM: OpenJDK 64-Bit Server VM 25.275-b01 (BellSoft)
+
+As you can see in the listing above actual connection, as a part of JMX handshake, is made to 192.168.100.1:34000. 
+That address is provided in RMI remote stub received during first step of JXM handshake.
+
+If address provided by JXM host is not routeable `--force-address` option could solve connectivity issue.