Add connection history and some automatic server create process.

client.py

@@ -26,7 +26,9 @@ SERVER_JAR_DIR = Path.home() / ".serverjar"
 CLIENT_CERT_DIR = Path.home() / ".serverjar" / "client" / "cert"
 CLIENT_CERT_SUFFIXES = {".pem", ".crt", ".cer"}
 CLIENT_HISTORY_FILE = Path.home() / ".serverjar" / "history" / "history.txt"
+CLIENT_CONNECTION_HISTORY_FILE = Path.home() / ".serverjar" / "history" / "connection_history.txt"
 CLIENT_LOG_DIR = Path.home() / ".serverjar" / "client" / "logs"
+DEFAULT_CONNECT_TIMEOUT = 10.0
 
 def add_client_cert(cert_path):
     source = Path(cert_path).expanduser()
@@ -94,6 +96,68 @@ def create_client_tls_context(log=None, warn=None):
 
     return context
 
+def get_connection_history(log=None, warn=None):
+    connection_history = []
+
+    if not CLIENT_CONNECTION_HISTORY_FILE.exists():
+        return []
+
+    if callable(log):
+        log("Searching existing connections history...")
+
+    try:
+        with CLIENT_CONNECTION_HISTORY_FILE.open(mode="r", encoding="utf-8") as f:
+            for line in f:
+                try:
+                    line = line.strip()
+                    if line.count(":") < 2:
+                        continue
+
+                    server_name, host, port = line.rsplit(":", 2)
+
+                    # Ignore unknown format line record
+                    if len(server_name) == 0 or len(host) == 0 or len(port) == 0:
+                        continue
+
+                    int(port)
+
+                    connection_history.append({
+                        "serverName": server_name,
+                        "host": host,
+                        "port": port,
+                    })
+                except ValueError:
+                    continue
+
+    except Exception as e:
+        if callable(warn):
+            warn(f"Unable to load connection history file: {e}")
+
+    return connection_history
+
+
+def save_connection_history(connection_history, log=None, warn=None):
+    if not connection_history:
+        return
+
+    CLIENT_CONNECTION_HISTORY_FILE.parent.mkdir(parents=True, exist_ok=True)
+
+    if callable(log):
+        log("Saving connection history file...")
+
+    try:
+        with CLIENT_CONNECTION_HISTORY_FILE.open(mode="w", encoding="utf-8") as f:
+            for server in connection_history:
+                server_name = server.get("serverName")
+                host = server.get("host")
+                port = server.get("port")
+                if not server_name or not host or not port:
+                    continue
+                f.write(f"{server_name}:{host}:{port}\n")
+    except Exception as e:
+        if callable(warn):
+            warn(f"Unable to save connection history file: {e}")
+
 
 def get_history(log=None, warn=None):
     if not CLIENT_HISTORY_FILE.exists():
@@ -227,6 +291,7 @@ class ServerJarClient(Application):
         self.cmds = []
         self.current_index = None
         self.history_draft = ""
+        self.connection_history = []
 
         @self.kb.add("c-c")
         def closing_kb(event):
@@ -426,6 +491,43 @@ class ServerJarClient(Application):
             self._log("History cleared")
             return True
 
+        def _enable_retry_mode(cmd):
+            self.args.retry = True
+            self._log("Auto-retry mode enabled")
+            return True
+
+        def _list_connection_history(cmd):
+            if len(self.connection_history) == 0:
+                self._log("No connection history exists.")
+                return True
+
+            for index, server in enumerate(self.connection_history):
+                self._log("{}: {}".format(index, server.get("serverName")))
+
+            return True
+
+        def _connect_to_record_server(cmd):
+            parts = cmd.split()
+            if len(parts) != 2:
+                self._err("Usage: _hc ${index}")
+                return True
+
+            try:
+                index = int(parts[1])
+                server = self.connection_history[index]
+                host = server.get("host")
+                port = int(server.get("port"))
+                if not host:
+                    raise ValueError("empty host")
+            except (ValueError, TypeError, IndexError):
+                self._err("Invalid index")
+                return True
+
+            connect_to_server(host, port)
+
+            return True
+
+
         cmd_map = {
             "_exit": {
                 "func": _shutdown,
@@ -459,10 +561,23 @@ class ServerJarClient(Application):
                 "func": _clear,
                 "description": "Clear the log area",
             },
+            "_retry": {
+                "func": _enable_retry_mode,
+                "description": "Reconnect to the remote server if connection fails",
+            },
             "_help": {
                 "func": _help,
                 "description": "Display the help message",
             },
+            "_lhc": {
+                "func": _list_connection_history,
+                "description": "List the connection history (Only list the server that have one connection is successful)",
+            }
+            ,
+            "_hc": {
+                "func": _connect_to_record_server,
+                "description": "Connect to the server listed in the connection history. (Usage: _hc ${index})",
+            }
         }
 
         if not command.strip():
@@ -513,6 +628,8 @@ class ServerJarClient(Application):
                             required=False)
         parser.add_argument('-r', '--retry', help="Retry when disconnect", action='store_true', default=False,
                             required=False)
+        parser.add_argument('--connect-timeout', type=float, default=DEFAULT_CONNECT_TIMEOUT,
+                            help="Socket connection timeout in seconds", required=False)
         parser.add_argument('--add-cert', help="Add server certificate", type=str, default=None, required=False)
 
         args = parser.parse_args()
@@ -541,6 +658,7 @@ class ServerJarClient(Application):
 
         # Save history
         save_history(self.cmds, self._log, self._warn)
+        save_connection_history(self.connection_history, self._log, self._warn)
 
         # Exit ui event loop
         self.full_exit()
@@ -600,6 +718,17 @@ class ServerJarClient(Application):
 
             self.invalidate()
 
+    def save_server(self, host, port):
+        for server in self.connection_history:
+            if server.get("host") == host and str(server.get("port")) == str(port):
+                return
+
+        self.connection_history.append({
+            "serverName": f"{host}:{port}",
+            "host": host,
+            "port": port,
+        })
+
     def client(self):
         ptk_clear()
 
@@ -627,10 +756,9 @@ class ServerJarClient(Application):
 
                 # Create connect
                 if self.args.no_tls:
-                    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
-                    s.connect((self.host, self.port))
+                    s = socket.create_connection((self.host, self.port), timeout=self.args.connect_timeout)
                 else:
-                    raw = socket.create_connection((self.host, self.port))
+                    raw = socket.create_connection((self.host, self.port), timeout=self.args.connect_timeout)
                     context = self.get_tls_context()
                     s = context.wrap_socket(raw, server_hostname=self.host)
 
@@ -649,6 +777,10 @@ class ServerJarClient(Application):
                     data = s.recv(4096)
                     if not data:
                         raise ConnectionError("Server closed")
+
+                    # Only save the server that have at least one connection is successful
+                    self.save_server(self.host, self.port)
+
                     buffer += data.decode("utf-8", errors="replace")
                     while "\n" in buffer:
                         line, buffer = buffer.split("\n", 1)
@@ -721,7 +853,7 @@ class ServerJarClient(Application):
 
             except (ConnectionError, OSError) as e:
                 if not self.closing_event.is_set():
-                    if self.args.retry:
+                    if self.args.retry and self.host is not None and self.port is not None:
                         self._warn(f"Disconnected: {e}, retrying...")
                     else:
                         self._err(f"Disconnected: {e}")
@@ -757,6 +889,7 @@ class ServerJarClient(Application):
         self.args = self.arguments_parser()
         self.layout.focus(self.input_area)
         self.cmds = get_history(self._log, self._warn)
+        self.connection_history = get_connection_history(self._log, self._warn)
         asyncio.create_task(self.consume_incoming())
 
         self.client_thread.start()

main.py

@@ -3,6 +3,7 @@ ServerJar
 
 Wei - 2026
 """
+import platform
 import re
 import signal
 import socketserver
@@ -17,11 +18,14 @@ import time
 import datetime
 import base64
 import hmac
+import ipaddress
+import shlex
 from pathlib import Path
 import click
 import yaml
 from utils.common import get_latest_version_minecraft, get_specific_version_paper_builds, \
-    download_server_jar, download_latest_build_paper_jar, get_latest_paper_version, download_vanilla_server_jar
+    download_server_jar, download_latest_build_paper_jar, get_latest_paper_version, download_vanilla_server_jar, \
+    read_server_properties, save_server_properties, activate_eula_file
 from utils.file_settings import FileSettings
 from utils.file_settings import required_list, required_value
 from cryptography import x509
@@ -89,6 +93,86 @@ def load_settings():
     return s
 
 
+def run_initial_server_start(args, server_dir: Path, timeout: float = 120.0):
+    click.echo("Starting server once to generate initial files...")
+    proc = subprocess.Popen(
+        args,
+        stdin=subprocess.PIPE,
+        stdout=subprocess.PIPE,
+        stderr=subprocess.STDOUT,
+        text=True,
+        bufsize=1,
+        cwd=server_dir,
+        encoding="utf-8",
+        errors="replace",
+    )
+
+    try:
+        output, _ = proc.communicate(timeout=timeout)
+    except subprocess.TimeoutExpired:
+        click.echo("Initial start is still running. Sending stop command...")
+        try:
+            if proc.stdin:
+                proc.stdin.write("stop\n")
+                proc.stdin.flush()
+        except OSError:
+            pass
+
+        try:
+            output, _ = proc.communicate(timeout=30)
+        except subprocess.TimeoutExpired:
+            click.echo("Server did not stop in time. Killing initial start process...")
+            proc.kill()
+            output, _ = proc.communicate()
+
+    if output:
+        for line in output.splitlines():
+            click.echo(f"[BOOT] {line}")
+
+    return proc.returncode
+
+
+def configure_initial_server_files(server_dir: Path, server_name: str, server_host: str, server_port: str,
+                                   property_overrides=None):
+    try:
+        properties = read_server_properties(server_dir)
+    except FileNotFoundError as e:
+        click.echo(click.style(f"Unable to read server.properties: {e}", fg="yellow"))
+    else:
+        property_values = {
+            "server-name": str(server_name),
+            "server-ip": str(server_host),
+            "server-port": str(server_port),
+        }
+        if property_overrides:
+            property_values.update(property_overrides)
+
+        for key, value in property_values.items():
+            properties[key] = (value, {})
+
+        save_server_properties(properties, server_dir)
+        click.echo("server.properties updated.")
+
+    try:
+        if activate_eula_file(server_dir):
+            click.echo("EULA activated.")
+        else:
+            click.echo(click.style("EULA was not activated.", fg="yellow"))
+    except FileNotFoundError as e:
+        click.echo(click.style(f"Unable to activate EULA: {e}", fg="yellow"))
+
+
+def parse_server_property_overrides(values):
+    overrides = {}
+    for value in values:
+        key, separator, property_value = value.partition("=")
+        key = key.strip()
+        if separator == "" or key == "":
+            raise click.ClickException(f"Invalid server property override: {value}. Use key=value.")
+        overrides[key] = property_value.strip()
+    return overrides
+
+
 @main.command()
 @click.option("--name", "-d", default="Unnamed Server", show_default=True, help="Server name")
 @click.option("--mc-version", "-m",
@@ -126,10 +210,13 @@ def load_settings():
               help="Hostname of the server", required=True)
 @click.option("--server-port", "-srp",
               help="Port of the server", required=True)
+@click.option("--server-property", "-sp", "server_properties", multiple=True,
+              help="server.properties override written after the first startup. Use key=value; can be repeated.")
 def create_server(name, mc_version, build, server_type, snapshot, latest, list_builds, filename, extra_args, java_exec_path,
-                  x_memory_initial, x_memory_maximum, nogui, custom_args, server_port, server_host):
+                  x_memory_initial, x_memory_maximum, nogui, custom_args, server_port, server_host, server_properties):
     server_dir = Path("servers", name)
     server_type = server_type.lower()
+    property_overrides = parse_server_property_overrides(server_properties)
 
     def prepare_server_dir():
         if server_dir.exists():
@@ -210,22 +297,32 @@ def create_server(name, mc_version, build, server_type, snapshot, latest, list_b
             exit("User aborted.")
             return
 
-    extra_args += "nogui" if nogui else ""
     args = [
         java_exec_path,
         "-Xms{}".format(x_memory_initial),
         "-Xmx{}".format(x_memory_maximum),
         "-jar",
         out.absolute().as_posix(),
-        extra_args,
     ]
+    if extra_args:
+        args.extend(shlex.split(extra_args))
+    if nogui:
+        args.append("nogui")
 
     if custom_args:
         print("Will use custom commands as replacement.")
-        args = custom_args
+        args = shlex.split(custom_args)
 
     print(f"Server command: {' '.join(args)}")
 
+    try:
+        return_code = run_initial_server_start(args, server_dir)
+        if return_code not in (0, None):
+            click.echo(click.style(f"Initial server start exited with code {return_code}.", fg="yellow"))
+        configure_initial_server_files(server_dir, name, server_host, server_port, property_overrides)
+    except Exception as e:
+        raise click.ClickException(f"Unable to bootstrap server files: {e}") from e
+
     with settings.edit() as s:
         print("Saving...")
         s["servers"].append({
@@ -292,6 +389,8 @@ class SocketServer:
             self._ssl_context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
             self._ssl_context.load_cert_chain(certfile=self.certfile, keyfile=self.keyfile)
 
+        self.commands = {}
+
     # -------------------------
     # Socket Server
     # -------------------------
@@ -339,11 +438,12 @@ class SocketServer:
             "__help": "Display this help message",
             "__list": "List available server shells",
             "__exit": "Close the current socket connection",
-            "__stop_all": "Stop all servers and close the socket server",
+            "__stop_all": "Stop all servers and close the socket server (TLS Support must be enabled)",
             "__c <server name>": "Connect to a server shell",
             "__d": "Disconnect from the current server shell",
             "__sync_log [fromDate:endDate]": "Sync saved log lines from the attached server. Empty syncs the latest 300 lines",
             "__download_log": "Download the attached server's saved log file",
+            "__system_info": "Show system information",
         }
         attached_commands = {
             "__status": "Show target server process status",
@@ -597,12 +697,18 @@ class SocketServer:
                                     self.request.sendall(b"[SYS] bye\n")
                                     return
                                 elif cmd == "__stop_all":
-                                    self.request.sendall(
-                                        f"[SYS] Stopping all servers...bye\n".encode("utf-8")
-                                    )
-                                    mgr.broadcast_all(mgr.tcp_server.clients, "[SYS] Server stopping... (Stop by remote client)")
-                                    mgr.stop_event.set()
-                                    return
+                                    if not mgr.enable_tls:
+                                        self.request.sendall(
+                                            f"[SYS] Command \"__stop_all\" only works when tls support is enabled.\n".encode("utf-8")
+                                        )
+                                    else:
+                                        self.request.sendall(
+                                            f"[SYS] Stopping all servers...bye\n".encode("utf-8")
+                                        )
+                                        mgr.broadcast_all(mgr.tcp_server.clients,
+                                                          "[SYS] Server stopping... (Stop by remote client)")
+                                        mgr.stop_event.set()
+                                        return
                                 elif cmd.startswith("__sync_log"):
                                     mgr.send_sync_log(self.request, current_server, cmd)
                                 elif cmd == "__download_log":
@@ -633,6 +739,14 @@ class SocketServer:
                                         f"[SYS] Disconnected from current server \"{current_server}\"'s shell.\n".encode(
                                             "utf-8")
                                     )
+                                elif cmd == "__system_info":
+                                    self.request.sendall(
+                                        f"[SYS] Connected clients number: {len(self.current_server_record)}\n"
+                                        f"[SYS] Hostname: {mgr.host}\n"
+                                        f"[SYS] Port: {mgr.port}\n"
+                                        f"[SYS] Working Directory: {os.getcwd()}\n"
+                                        f"[SYS] Platform: {platform.system()} ({platform.architecture()[0]})\n"
+                                        f"[SYS] Version: {VERSION}\n".encode("utf-8"))
                                 else:
                                     if current_server is not None:
                                         receiver = mgr.get_command_receiver(current_server)
@@ -887,12 +1001,12 @@ class Server:
 
     def _stdout_reader_loop(self):
         self.logger.info("[PROC] stdout reader started")
-        while self.running:
+        while True:
             with self.proc_lock:
                 proc = self.proc
                 out = proc.stdout if proc else None
 
-            if not proc or proc.poll() is not None or not out:
+            if not proc or not out:
                 self.logger.info("[PROC] process ended / stdout closed")
                 break
 
@@ -915,8 +1029,11 @@ class Server:
             if not self.proc.stdin:
                 return False
 
-            self.proc.stdin.write(command + "\n")
-            self.proc.stdin.flush()
+            try:
+                self.proc.stdin.write(command + "\n")
+                self.proc.stdin.flush()
+            except OSError:
+                return False
             return True
 
     def stop_process(self, timeout: float = 10.0):
@@ -959,9 +1076,9 @@ class Server:
             return
 
         self.stopping = True
-        self.running = False
 
         self.stop_process()
+        self.running = False
 
     def restart(self):
         if self.running:
@@ -995,7 +1112,7 @@ class Server:
             return True, f"Server \"{self.name}\" process started"
         elif command == "__info":
             return True, (f"serverName: {self.name}\n"
-                          f"serverPID: {self.proc.pid}\n"
+                          f"serverPID: {self.proc.pid if self.proc else None}\n"
                           f"description: {self.description}\n"
                           f"arguments: {self.args}\n"
                           f"host: {self.host}\n"
@@ -1012,8 +1129,11 @@ class Server:
             if not self.proc.stdin:
                 return False, "Process standard input are not available."
 
-            self.proc.stdin.write(command + "\n")
-            self.proc.stdin.flush()
+            try:
+                self.proc.stdin.write(command + "\n")
+                self.proc.stdin.flush()
+            except OSError as e:
+                return False, f"Unable to write process standard input: {e}"
             return True, "Command sent."
 
 def load_all_server_from_settings(settings: FileSettings):
@@ -1138,7 +1258,8 @@ def runserver(keep_running: bool):
     logger.info("Stopped!")
 
 @main.command()
-def generate_tls_key():
+@click.option("--hostname", default="localhost", show_default=True, help="Hostname or IP address of the server.")
+def generate_tls_key(hostname: str):
     print("Generating TLS key...")
     key = rsa.generate_private_key(
         public_exponent=65537,
@@ -1150,9 +1271,23 @@ def generate_tls_key():
         x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, u"California"),
         x509.NameAttribute(NameOID.LOCALITY_NAME, u"San Francisco"),
         x509.NameAttribute(NameOID.ORGANIZATION_NAME, u"My Dev Org"),
-        x509.NameAttribute(NameOID.COMMON_NAME, u"localhost"),
+        x509.NameAttribute(NameOID.COMMON_NAME, u"{}".format(hostname)),
     ])
 
+    alt_names = [x509.DNSName(u"localhost")]
+
+    def add_alt_name(name):
+        if name not in alt_names:
+            alt_names.append(name)
+
+    try:
+        add_alt_name(x509.IPAddress(ipaddress.ip_address(hostname)))
+    except ValueError:
+        add_alt_name(x509.DNSName(hostname))
+
+    for loopback in ("127.0.0.1", "::1"):
+        add_alt_name(x509.IPAddress(ipaddress.ip_address(loopback)))
+
     cert = x509.CertificateBuilder().subject_name(
         subject
     ).issuer_name(
@@ -1167,7 +1302,7 @@ def generate_tls_key():
         # Valid for 1 year
         datetime.datetime.now(datetime.UTC) + datetime.timedelta(days=365)
     ).add_extension(
-        x509.SubjectAlternativeName([x509.DNSName(u"localhost")]),
+        x509.SubjectAlternativeName(alt_names),
         critical=False,
     ).sign(key, hashes.SHA256())
 

requirements.txt

@@ -1,2 +1,3 @@
 prompt-toolkit==3.0.52
-cryptography==48.0.0
+cryptography==48.0.0
+jproperties==2.1.2

utils/common.py

@@ -2,11 +2,56 @@ from pathlib import Path
 import requests
 import click
 import os
+from jproperties import Properties
 
 PAPER_VERSION_API = "https://api.papermc.io/v2/projects/paper/versions/{}"
 PAPER_SERVER_JAR_API = "https://api.papermc.io/v2/projects/paper/versions/{}/builds/{}/downloads/paper-{}-{}.jar"
 MOJANG_VERSION_MANIFEST_V2 = "https://piston-meta.mojang.com/mc/game/version_manifest_v2.json"
 
+def read_server_properties(server_dir: Path) -> Properties:
+    if not server_dir.exists():
+        raise FileNotFoundError("Server directory does not exist")
+
+    props = Properties()
+
+    with open(server_dir / 'server.properties', 'rb') as config_file:
+        props.load(config_file, encoding='utf-8')
+        return props
+
+
+def save_server_properties(properties: Properties, server_dir: Path) -> None:
+    path = server_dir / 'server.properties'
+
+    with path.open("wb") as config_file:
+        properties.store(config_file, encoding='utf-8')
+
+def activate_eula_file(server_dir: Path) -> bool:
+    path = server_dir / 'eula.txt'
+
+    if not path.exists():
+        raise FileNotFoundError("EULA file does not exist. Did you run the server?")
+
+    with open(path, 'r', encoding='utf-8') as file:
+        lines = file.readlines()
+
+    for line in lines:
+        print(f"{line}\n")
+
+    print("To activate eula file please read above text. If you agree this license, enter Y [not agree enter N]")
+    result = str(input("Agree? :"))
+
+    if result.strip().lower() != "y":
+        return False
+
+    with open(path, 'w', encoding='utf-8') as file:
+        for line in lines:
+            if line.strip() == "eula=false":
+                file.write("eula=true\n")
+                continue
+            file.write(line)
+
+
+    return True
 
 def jar_filename(filename: str | None, default: str) -> str:
     if filename:

utils/explorer_library.py

@@ -0,0 +1,102 @@
+"""
+Source are from KiteeLauncher.
+"""
+import os
+import re
+import subprocess
+import tempfile
+
+
+def check_java_executable_and_major_version(java_executable_path):
+    # test java runtimes are executable
+    try:
+        subprocess.run([java_executable_path], stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
+        return True, None
+    except PermissionError:
+        return False, "Could not execute the Java executable. Permission denied."
+    except Exception as e:
+        return False, "Unknown error occurred while executing the Java executable. {}".format(e)
+
+
+def get_java_version_by_execute(java_executable_path):
+    # test java runtimes are executable
+
+    # executable it
+    try:
+        result = subprocess.run([java_executable_path, '-version'], stderr=subprocess.PIPE, stdout=subprocess.PIPE,
+                                text=True)
+    except PermissionError:
+        return False, None, "Could not execute the Java executable. Permission denied."
+    except Exception as e:
+        return False, None, "Unknown error occurred while executing the Java executable. {}".format(e)
+
+    # Get output
+    output = result.stderr
+
+    # Get major version (e.g., "21.0.3") and full version in the output
+    match = re.search(r'java version "(\d+)(?:\.(\d+))?', output)
+
+    # Is for installation by launcher runtimes (Because is openjdk not oracle java....)
+    if not match:
+        match = re.search(r'openjdk version "(\d+)(?:\.(\d+))?', output)
+
+        if not match:
+            return False, None, "Unsupported Java runtime build or current path is not a valid java executable."
+
+    try:
+        major_version = match.group(1)
+        # Special case for Java 8 where we need to use the second part (8) instead of 1
+        if major_version == "1" and match.group(2):
+            major_version = match.group(2)
+        return True, major_version, None
+    except IndexError:
+        return False, None, "The target Java runtime version is too old or is not supported by this method."
+
+def convert_java_version_tuple_to_major_version(java_version_tuple):
+    try:
+        _, major_version, *_ = java_version_tuple.split(".")
+        return True, major_version
+    except ValueError:
+        return False, None
+
+
+def get_java_version_by_checkmyduke(java_executable_path):
+    checkmyduke_jar = os.path.join("jar_files", "CheckMyDuke.jar")
+
+    if not os.path.exists(checkmyduke_jar):
+        return False, None, "CheckMyDuke.jar not found"
+
+    # executable it
+    try:
+        result = subprocess.run([java_executable_path, '-jar', checkmyduke_jar], stderr=subprocess.PIPE, stdout=subprocess.PIPE,
+                                text=True)
+    except PermissionError:
+        return False, None, "Could not execute the Java executable. Permission denied."
+    except Exception as e:
+        return False, None, "Unknown error occurred while executing the Java executable. {}".format(e)\
+
+
+    status, major_version = convert_java_version_tuple_to_major_version(result.stdout.strip())
+
+    if status:
+        return True, major_version, None
+    else:
+        return False, None, "Unsupported Java runtime build or current path is not a valid java executable."
+
+def search_available_java_runtimes_in_directory(target_directory, java_executable_name="java.exe" if os.name == "nt" else "java"):
+    """
+    Using this function may take ~1min to search for available Java executable files.
+    """
+    found_java_runtimes = []
+
+    for root, dirs, files in os.walk(target_directory):
+        for file in files:
+            if file == java_executable_name:
+                found_java_runtimes.append(os.path.join(root, file))
+
+
+    return found_java_runtimes
+
+
+
+