I have a program that loads a text file holding some information and based on that information it runs multiple thread. Each thread is a process. Here is my code:
public class runMultiClient {
public static void main(String[] args){
List<Process> PRlist = new ArrayList<Process>();
List<String[]> commandsList = new ArrayList<String[]>();
boolean running = true;
if (args.length == 2 && args[0].matches("-f")){
String dir = System.getProperty("user.dir");
String path = dir + "/" + args[1];
FileReader fr;
try {
fr = new FileReader(path);
BufferedReader bf = new BufferedReader(fr);
String line = "";
while ((line = bf.readLine()) != null){
String[] tk = line.split(" ");
String[] cmd = {"java", "-jar", "Client.jar", "-a", tk[0], "-p", tk[1],
"-u", tk[2], "-pw", tk[3], "-m", tk[4], "-s", tk[5]};
Process pr = new ProcessBuilder().inheritIO().command(cmd).start();
PRlist.add(pr);
commandsList.add(cmd);
System.out.println(tk[4] + " streaming process is established.");
}
}
catch (FileNotFoundException ex) {ex.printStackTrace();}
catch (IOException ex) {ex.printStackTrace();}
} else {
System.out.println("No stream file was specified.");
}
}}
Inside my Client.jar file, i have a variable that monitors the cpu load of that class:
OperatingSystemMXBean osBean = ManagementFactory.getPlatformMXBean(OperatingSystemMXBean.class);
cpuLoad = osBean.getProcessCpuLoad();
Is there any way i can reach that variable from the runMultiClient class?
If not, is there any way of using the OperatingSystemMXBean on the running process?
I have tried pr.getClass(), but it got me nowhere.
Any help would be appreciated.
Option #1: Add agent library and expose JMX over HTTP
You can bundle Jolokia agent with your monitored application (another similar thing is SimpleJMX. It exposes JMX beans over http/json so this works for interacting with JMX from other languages like python (and super comfy when troubleshooting from command like). After that you can access mbeans of your interest via apache http client or the like.
Option #2: JMX client
allow remote connections by adding the following params when starting your monitored application:
-Dcom.sun.management.jmxremote.port=9999 \
-Dcom.sun.management.jmxremote.authenticate=false \
-Dcom.sun.management.jmxremote.ssl=false
Then you should be able to access the mbeans by jconsole and hand written JMX client code, like in the tutorial
Not sure if you need to call ProcessBuilder().inheritIO() for some other requirement, but if not, you could start a daemon thread in your Client.jar process that periodically writes the cpu load to System.out. Then your runMultiClient thread[s] could read those from the InputStream representing the process's System.out. Or, have the thread accept commands and print accordingly. Rough example:
Run this in the spawned Client.jar:
public static void startCmdListener() {
try {
Thread t = new Thread("CmdListener") {
BufferedReader br = null;
InputStreamReader isr = null;
final OperatingSystemMXBean os = (OperatingSystemMXBean) ManagementFactoryHelper.getOperatingSystemMXBean();
public void run() {
try {
isr = new InputStreamReader(System.in);
br = new BufferedReader(isr);
} catch (Exception ex) {
ex.printStackTrace(System.err);
return;
}
try {
String cmd = null;
while(true) {
cmd = br.readLine();
if("cpu".equalsIgnoreCase(cmd)) { // cpu command, print the process load
System.out.println(os.getProcessCpuLoad());
} else if("exit".equalsIgnoreCase(cmd)) { // exit command, break
break;
}
}
} catch (Exception ex) {
ex.printStackTrace(System.err);
return;
}
}
};
t.setDaemon(true);
t.start();
} catch (Exception ex) {
ex.printStackTrace(System.err);
}
}
Run this in the runMultiClient to get the cpu load:
public static double getCpu(OutputStream processIn, InputStream processOut) {
PrintStream ps = null;
BufferedReader br = null;
InputStreamReader isr = null;
try {
ps = new PrintStream(processIn);
isr = new InputStreamReader(processOut);
br = new BufferedReader(isr);
ps.println("cpu");
ps.flush();
return Double.parseDouble(br.readLine());
} catch (Exception ex) {
throw new RuntimeException(ex);
} finally {
if(ps!=null) try { ps.close(); } catch (Exception x) {}
if(br!=null) try { br.close(); } catch (Exception x) {}
if(isr!=null) try { isr.close(); } catch (Exception x) {}
}
}
Related
I'm having trouble starting an application from my JavaFX GUI. I'm using ProcessBuilder. It creates the process, but the application won't launch until I close my Java program. Is it because that specific program is waiting for arguments or something wrong with my code?
#FXML
private void runWorldpac() {
try {
ProcessBuilder process = new ProcessBuilder("C:\\speedDIAL\\speedDIAL.exe");
Process p = process.start();
} catch (IOException e) {
e.printStackTrace();
}
}
External application starts but won't allow any interaction with the original application until i close this external program. Tried running a new thread, same result.
Here's the new code:
try {
ProcessBuilder process = new ProcessBuilder("C:\\speedDIAL\\speedDIAL.exe");
Map<String, String> environ = process.environment();
Process p = process.start();
InputStream is = p.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
String line;
while ((line = br.readLine()) != null) {
//System.out.println(line);
}
System.out.println("Program terminated!");
} catch (IOException e) {
e.printStackTrace();
}
Read that article, good info. Also read another good example on here. It's running in a new thread now, but my program is waiting for the external application to finish before it continues, I understand that's usually desired, but not in this case, how can i disable that?
Wait for the production of the exit value in a new thread. Something like:
try {
ProcessBuilder pBuilder = new ProcessBuilder("C:\\speedDIAL\\speedDIAL.exe");
// don't forget to handle the error stream, and so
// either combine error stream with input stream, as shown here
// or gobble it separately
pBuilder.redirectErrorStream(true);
final Process process = pBuilder.start();
final InputStream is = process.getInputStream();
// in case you need to send information back to the process
// get its output stream. Don't forget to close when through with it
final OutputStream os = process.getOutputStream();
// thread to handle or gobble text sent from input stream
new Thread(() -> {
// try with resources
try (BufferedReader reader = new BufferedReader(new InputStreamReader(is));) {
String line = null;
while ((line = reader.readLine()) != null) {
// TODO: handle line
}
} catch (IOException ex) {
ex.printStackTrace();
}
}).start();
// thread to get exit value from process without blocking
Thread waitForThread = new Thread(() -> {
try {
int exitValue = process.waitFor();
// TODO: handle exit value here
} catch (InterruptedException e) {
e.printStackTrace();
}
});
waitForThread.start();
// if you want to join after a certain time:
long timeOut = 4000;
waitForThread.join(timeOut);
} catch (IOException | InterruptedException e) {
e.printStackTrace();
}
In my Java application I am using the exec() command to call a terminal function:
p = Runtime.getRuntime().exec(command);
p.waitFor();
The call uses the zip and unzip calls. Originally I call:
zip -P password -r encrypted.zip folderIWantToZip
When I call the unzip function through java, I specify the password as the method parameter. If the correct password is specified then the call should unzip the encrypted folder:
unzip -P password encrypted.zip
I want a way to find out if the password entered is incorrect. For example, if password is correct, then the call will correctly unzip the zip file. But I notice that no exception is thrown for an incorrect password. How can I determine this?
You could read the process's ErrorStream and InputStream to determine the process output. Sample code given below
public static void main(String[] args) {
try {
String command = "zip -P password -r encrypted.zip folderIWantToZip";
Process p = Runtime.getRuntime().exec(command);
InputStream is = p.getInputStream();
int waitFor = p.waitFor();
BufferedReader reader = new BufferedReader(new InputStreamReader(is));
String line;
while ((line = reader.readLine()) != null) {
System.out.println("line:" + line);
}
is = p.getErrorStream();
reader = new BufferedReader(new InputStreamReader(is));
while ((line = reader.readLine()) != null) {
System.out.println("ErrorStream:line: " + line);
}
System.out.println("waitFor:" + waitFor);
System.out.println("exitValue:" + p.exitValue());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
You could use the exitcode to validate the process status as well but it is specific to to program. Normally zero means successfully terminated otherwise abnormal termination.
As per my comment, first thing I would do would be to capture the Process's InputStream and ErrorStream via getInputStream() and getErrorStream(), but especially the latter, the ErrorStream, and check to see what it outputs if the input is in error. Note that these would have to be done in their own thread, else you'll tie up your program. I usually use some type of StreamGobbler class for this. Also, don't ignore the int returned by p.waitFor().
e.g.,
ProcessBuilder pBuilder = new ProcessBuilder(COMMAND);
Process process = null;
try {
process = pBuilder.start();
new Thread(new StreamGobbler("Input", process.getInputStream())).start();
new Thread(new StreamGobbler("Error", process.getErrorStream())).start();
int exitValue = process.waitFor();
System.out.println("Exit Value: " + exitValue);
process.destroy();
} catch (IOException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
} finally {
if (process != null) {
process.destroy();
}
}
And:
class StreamGobbler implements Runnable {
private String name;
private Scanner scanner;
public StreamGobbler(String name, InputStream inputStream) {
this.name = name;
scanner = new Scanner(inputStream);
}
#Override
public void run() {
while (scanner.hasNextLine()) {
String line = scanner.nextLine();
System.out.println(name + ": " + line); // or better, log the line
}
scanner.close();
}
}
With the code below, I'm trying to simulate the command shell, I even created a command and called it (Showerrlog) to help the user seeing his invalid commands that he entered during his current work session, as you can see, I did that using filehandler, which will save the wrong commands in a log file. But as you know filehandler will start a new file for each new working session, and the new file will be named as (file.log, file.log.1, file.log.2, etc) and so on, the question is: how to make the program to avoid opening a new file everytime, in other words isn't there any other way that the program will just format the previous work session and add the new one instead?
Or at least how to make the program open the last log file which belongs to the current work session ?
public class WithEyul implements Runnable {
String command;
public WithEyul(String command) {
this.command = command;
}
#Override
public void run() {
List<String> input = new ArrayList<String>();
StringTokenizer tokenizer = new StringTokenizer(command);
while (tokenizer.hasMoreTokens()) {
input.add(tokenizer.nextToken());
}
ProcessBuilder pb = new ProcessBuilder(input);
// ProcessBuilder creates a process corresponding to the input command
// now start the process
BufferedReader br = null;
try {
Process proc = pb.start();
// obtain the input and output streams
InputStream is = proc.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
br = new BufferedReader(isr);
// read what the process returned
String line;
while ((line = br.readLine()) != null) {
System.out.println(line);
}
br.close();
} catch (java.io.IOException ioe) {
try {
System.err.println("Error");
Logger logger = Logger.getLogger("Testing");
FileHandler fh = new FileHandler("E:/MyLogFile.log");
logger.addHandler(fh);
SimpleFormatter formatter = new SimpleFormatter();
fh.setFormatter(formatter);
logger.info(command);
} catch (SecurityException e) {
printStackTrace();
} catch (IOException ex) {
Logger.getLogger(WithEyul.class.getName()).log(Level.SEVERE, null, ex);
}
} finally {
if (br != null) {
try {
br.close();
} catch (IOException ex) {
Logger.getLogger(WithEyul.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
}
}
and here is the main method class
public class TestProcessBuilder {
static void createProcess(String command) throws java.io.IOException {
Thread t = new Thread(new WithEyul(command));
t.start();
}
public static void main(String[] args) throws java.io.IOException {
String commandLine;
File wd;
BufferedReader console = new BufferedReader(new InputStreamReader(System.in));
System.out.println("\n\n***** Welcome to the Java Command Shell *****");
System.out.println("If you want to exit the shell, type END and press RETURN.\n");
// we break out with ‘END’
while (true) {
// show the Java shell prompt and read what command they entered
System.out.print("jsh>");
commandLine = console.readLine();
// if user entered a return, just loop again
if (commandLine.equals("")) {
continue;
}
if (commandLine.equalsIgnoreCase("Showerrlog")) {
try {
// Runtime.getRuntime().exec("E:\\MyLogFile.log");
if (Desktop.isDesktopSupported()) {
Desktop.getDesktop().open(new File("E:\\MyLogFile.log"));
}
} catch (IOException ex) {
Logger.getLogger(WithEyul.class.getName()).log(Level.SEVERE, null, ex);
}
}
if (commandLine.toLowerCase().equals("end")) { //User wants to end shell
System.out.println("\n***** Command Shell Terminated. See you next time. BYE for now. *****\n");
System.exit(0);
}
createProcess(commandLine);
}
}
}
You could use the FileHandler constructor that allows you to specify the rotation, limit, and append options.
new FileHandler("E:/MyLogFile.log", 0, 1, true);
The FileHandler can rotate for a number of reasons that are out of your control. If you don't want to deal with file rotation you could open a FileOutputStream and wrap that with a StreamHandler. However, you will have to handle file locking conflicts.
You should also avoid creating and adding a handler that points to the same target file everytime an error is generated. You should install the handler on startup and store a string reference to your logger.
I am trying to execute a c++ code from java on a remote Windows machine. In order to deal with the remote part, I have created a Web service from where the actual command is run using Runtime.exec(). The c++ exe is not being called directly from the java code. I have a batch file that eventually calls the exe.
The problem is, both java and c++ processes hang. The java code on server side does handle the output stream and error stream. Also, the c++ code is logging everything in a file on Windows. The strange thing is that, when I remove the WS call and run the java code on server side as a standalone java program, it succeeds. Here is the java code:
public class RunCPlusPlusExecutable {
public int runExecutable() {
int exitValue = 0;
try {
Process p = null;
Runtime rt = Runtime.getRuntime();
System.out.println("About to execute" + this + rt);
p = rt.exec("c:/temp/execcplusplus.bat");
System.out.println("Process HashCode=" + p.hashCode());
StreamProcessor errorHandler = new StreamProcessor(p.getErrorStream(), "Error");
StreamProcessor outputHandler = new StreamProcessor(p.getInputStream(), "Output");
errorHandler.start();
outputHandler.start();
exitValue = p.waitFor();
System.out.println("Exit value : " + exitValue);
if (exitValue == 0)
System.out.println("SUCCESS");
else
System.out.println("FAILURE");
} catch (IOException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
} catch (Exception e) {
}
return exitValue;
}
class StreamProcessor extends Thread {
private InputStream is = null;
private String type = null;
private InputStreamReader isr = null;
private BufferedReader br = null;
private FileWriter writer = null;
private BufferedWriter out = null;
StreamProcessor(InputStream is, String type) {
this.is = is;
this.type = type;
}
public void run() {
try {
isr = new InputStreamReader(is);
br = new BufferedReader(isr);
writer = new FileWriter("*******path to log file********");
out = new BufferedWriter(writer);
String line = null;
while ((line = br.readLine()) != null) {
Date date = new Date();
out.write("[" + type + "]: " + date + " : " + line);
out.newLine();
}
writer.flush();
} catch (IOException ioe) {
ioe.printStackTrace();
} finally {
try {
if (br != null)
br.close();
if (isr != null)
isr.close();
if (out != null)
out.close();
if (writer != null)
writer.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
Any idea what is causing the problem and how to debug it? Please note that I won't be able to debug the c++ code.
Thanks
Update 1:
Here are some more details...
The WS server is running from some admin user. And I have been running the standalone java program from some other user.
*It seems that the c++ executable is giving referenced memory error while executing from WS call. There are pop-ups citing the error with OK and Cancel buttons. *
Update 2:
The tomcat server where the WS is deployed is running as a Windows NT service. Can that be the cause of the error? If yes, how to resolve this?
I've created a WebApp that relies on external scripts to gather query request by the user (internal software). I've tested, with sucess, the WebApp off the glassfish server provided by netbeans but whenever I try and upload my App to a third party server (Apache Tomcat) I run into the issue of the process.getRuntime exitValue never being written and the WebApp never gets to the result page....
This is the code that I have implemented so far:
Update --> The code now works after reading both stderr and stdin:
pd = new ProcessBuilder("runscript.bat");
pd.redirectErrorStream(true);
process = pd.start();
StreamGobbler inputGobbler = new StreamGobbler(process.getInputStream(), "Input");
StreamGobbler errorGobbler = new StreamGobbler(process.getErrorStream(),"Error");
errorGobbler.start();
inputGobbler.start();
int exitVal = -1;
try {
exitVal = process.waitFor();
} catch (InterruptedException ex) {
//log Error
}
class StreamGobbler extends Thread {
OutputWriterReader outWR = new OutputWriterReader();
BufferedWriter deadWriter;
InputStream is;
// reads everything from is until empty.
StreamGobbler(InputStream is, String type) {
this.is = is;
createWatch(type);
}
// depending on if Error stream or Input Stream
private void createWatch(String type){
try {
if(type.equals("Error"))
deadWriter = new BufferedWriter(new FileWriter("StdError.txt"));
else if(type.equals("Input"))
deadWriter = new BufferedWriter(new FileWriter("StdInput.txt"));
} catch (IOException ex) {
//log Error
}
}
#Override
public void run() {
try {
InputStreamReader isr = new InputStreamReader(this.is);
BufferedReader br = new BufferedReader(isr);
String line=null;
while ( (line = br.readLine()) != null)
deadWriter.append(line);
deadWriter.flush();
deadWriter.close();
} catch (IOException ioe) {
//log Error
}
}
}
Any Suggerstions? Thanks in advance for any help
The process may not be complete when you call exitValue() on it.
Before process.exitValue() call add:
process.waitFor();