Java does not have primitives for ICMPs and traceroute. How to overcome this? Basically I'm building code that should run in *nix and Windows, and need a piece of code that will run in both platforms.
Here's what I wrote today to "implement" the trace route command in Java. I've only tested in windows but it should work in Linux as well although there are several traceroute tools available for Linux so most likely there need to be some checks for the existence of those programs.
public class NetworkDiagnostics{
private final String os = System.getProperty("os.name").toLowerCase();
public String traceRoute(InetAddress address){
String route = "";
try {
Process traceRt;
if(os.contains("win")) traceRt = Runtime.getRuntime().exec("tracert " + address.getHostAddress());
else traceRt = Runtime.getRuntime().exec("traceroute " + address.getHostAddress());
// read the output from the command
route = convertStreamToString(traceRt.getInputStream());
// read any errors from the attempted command
String errors = convertStreamToString(traceRt.getErrorStream());
if(errors != "") LOGGER.error(errors);
}
catch (IOException e) {
LOGGER.error("error while performing trace route command", e);
}
return route;
}
You'll need the jpcap library (maybe the SourceForge jpcap is working too) and use the ICMPPacket class to implement the desired functionality.
Here is the Java traceroute implementation using the jpcap library .
Related
I am trying to use Microsoft Speech API text-to-speech, in my java project for Android. It's not working. Is it possible to use this API in java?
The speech-to-text is working, I found the Quickstart and had no problem using it.
However, there is no java example for text-to-speech, only in C#, C++ (Windows) and C++ (Linux).
I tried to adapt the code in java, but it's not working and I have no idea why.
public void onTextToSpeechButtonClicked(View v) {
TextView txt = (TextView) this.findViewById(R.id.texttospeech); // 'texttospeech' is the ID of my text view
try {
// THIS LINE ISN'T WORKING
com.microsoft.cognitiveservices.speech.internal.SpeechConfig config = com.microsoft.cognitiveservices.speech.internal.SpeechConfig.FromSubscription(speechSubscriptionKey, serviceRegion);
config.SetSpeechRecognitionLanguage("fr-FR");
assert(config != null);
// Creates a speech synthesizer using the default speaker as audio output
SpeechSynthesizer synthesizer = SpeechSynthesizer.FromConfig(config);
assert(synthesizer != null);
SpeechSynthesizer synthesizer1 = SpeechSynthesizer.FromConfig(config);
SpeechSynthesisResult result = synthesizer.SpeakTextAsync(txt.toString()).Get();
// Checks result
if (result.getReason().equals(ResultReason.SynthesizingAudioCompleted)){
txt.setText("The text has been said.");
}
else if (result.getReason().equals(ResultReason.Canceled)){
SpeechSynthesisCancellationDetails cancellation = SpeechSynthesisCancellationDetails.FromResult(result);
txt.setText("CANCELED: Reason ="+cancellation.getReason());
if(cancellation.getReason().equals(CancellationReason.Error)){
txt.append("ErrorCode = "+cancellation.getErrorCode()+" / ErrorDetails = "+cancellation.getErrorDetails()+" / Did you update the subscription info ?");
}
}
synthesizer.delete();
} catch (Exception ex) {
Log.e("SpeechSDKDemo", "unexpected " + ex.getMessage());
assert(false);
}
}
What I have in the log is that:
E/ples.quickstar: No implementation found for void com.microsoft.cognitiveservices.speech.internal.carbon_javaJNI.swig_module_init() (tried Java_com_microsoft_cognitiveservices_speech_internal_carbon_1javaJNI_swig_1module_1init and Java_com_microsoft_cognitiveservices_speech_internal_carbon_1javaJNI_swig_1module_1init__)
D/AndroidRuntime: Shutting down VM
--------- beginning of crash
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.microsoft.cognitiveservices.speech.samples.quickstart, PID: 4106
java.lang.IllegalStateException: Could not execute method for android:onClick
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:389)
at android.view.View.performClick(View.java:6597)
at...
Can someone help me?
I searched if Microsoft Speech API is compatible with Java and the answer is no. It also seems a little obvious because Microsoft = C++ / C# which is nothing similar to Java.
In addition, in your post you mentionned the Quickstart. This uses the Cognitive Services Speech SDK and not Microsoft SAPI.
However, there are native Java libraries allowing Text-To-Speech. Here is a post related to Text-To-Speech engines. Here is more information about it.
There are also libraries available for Android:
Using the Text-To-Speech engine
Android documentation
I would suggest an alternative. Why not try to use windows tts instead by sending the text to a powershell command which can be executed from java code:
String[] command = {"powershell.exe", "Add-Type -AssemblyName System.Speech; (New-Object System.Speech.Synthesis.SpeechSynthesizer).Speak('" + message +"');"};
try {
ProcessBuilder pb = new ProcessBuilder(command);
Process process = pb.start();
System.out.format("Process exit code: %d", process.waitFor());
ProcessInputOutput.readStdnOutput(process);
}
catch (Exception e){
e.printStackTrace();
}
I want to write Syslog using in java program on linux system. I don't want to use any library.
Assuming that "no libraries" means no 3rd-party libraries.
One approach would be to code your own implementation of the Syslog Protocol; see RFC 5424. You could do this in pure Java.
CORRECTION - Actually, not pure Java. The syslog protocol (typically) uses UNIX Domain sockets, and there is no built-in Java library functionality for this. You would need to resort to native code, or a 3rd-party library; see UNIX Domain Socket in Java
A second approach would be to write a JNI wrapper for the syslog(3) C library methods. Under the hood, this library opens a datagram socket on a local port and (presumably) implements the Syslog Protocol. So you don't achieve much by doing it this way.
(Note that the C libraries are part of (at least) any GNU/Linux system, so this doesn't count as using a 3rd-party library. At least, not in my books ...)
I used the system logger with a Runtime like this:
public static void log(String TextToLog){
Runtime r = Runtime.getRuntime();
try{
r.exec("logger \"Applicationname " + TextToLog + "\"");
}
catch(IOException e){e.printStackTrace();}
}
If the distribution uses systemd, you can use the following.
String logMessage = "some message";
String logIdentifier = "java-app";
String command = "echo " + logMessage + " | systemd-cat -t " + logIdentifier;
new ProcessBuilder(new String[] {"bash","-c","eval " + command}).start();
To watch in GNU/Linux's terminal, watch for your logIdentifier:
watch -n0.5 sudo journalctl -t "java-app"
I need to compile and run source code (single file), written in Python, Pascal or C, from my Java application.
I will need to know:
if compile process was successful
the return output of the compiled program
How could I accomplish that?
I have been doing the same thing..
public String compile()
{
String log="";
try {
String s= null;
//change this string to your compilers location
Process p = Runtime.getRuntime().exec("cmd /C \"C:\\Program Files\\CodeBlocks\\MinGW\\bin\\mingw32-g++.exe\" temp.cpp ");
BufferedReader stdError = new BufferedReader(new
InputStreamReader(p.getErrorStream()));
boolean error=false;
log+="\n....\n";
while ((s = stdError.readLine()) != null) {
log+=s;
error=true;
log+="\n";
}
if(error==false) log+="Compilation successful !!!";
} catch (IOException e) {
e.printStackTrace();
}
return log;
}
public int runProgram()
{
int ret = -1;
try
{
Runtime rt = Runtime.getRuntime();
Process proc = rt.exec("cmd.exe /c start a.exe");
proc.waitFor();
ret = proc.exitValue();
} catch (Throwable t)
{
t.printStackTrace();
return ret;
}
return ret;
}
This are 2 functions used in my MiDE first one used to compile. Change the address to your compilers location. and returns the log(in case compilation was failed) to see the errors.
The 2nd one runs the compiled code. Returning the exit code to check whether it terminated correctly.
I am not a very good java coder . i guess you can improve my code a lot better ;) .. in case you do please inform me. And i am also looking for a answer on how to communicate with the created process
You could use java.lang.ProcessBuilder to execute commands and check the status.
Here JAVADOC : http://download.oracle.com/javase/1.5.0/docs/api/java/lang/ProcessBuilder.html
In general, you'll want to launch a Process that runs the external program (first the compiler, and then the compiled binary in your case), using either Runtime.getRuntime().exec() or a ProcessBuilder to spawn the Process (since your compiler probably takes a complicated set of options, the ProcessBuilder is likely a better option). This will allow you to grab the output from the process as it executes (so you can monitor the compiler output for warnings or errors), as well as its return code.
You may find the following examples helpful:
http://www.rgagnon.com/javadetails/java-0014.html
To get the return code of a running Process, just use the waitFor() method. This is convenient if you don't care about any of the output and just want the return value.
You're probably going to want to use Runtime.exec() to call the respective compiler. Check out the JavaDoc for more information about how to deal with the output, etc.
If you're mainly doing code snippets you might try running Python code using Jython. See Howto multithreaded jython scripts running from java? for details.
Greetings,
I would like to ask if there's a way to block website(s) from access on a computer(s) dynamically? I mean could this functionality be coded (on java native interface)?
Your response is highly appreciated.
Thanks,
Cyril H.
Yes, you can code a simple HTTP proxy service with Java:
http://www.java2s.com/Code/Java/Network-Protocol/Asimpleproxyserver.htm
Alternatively, there are plenty of existing proxy solutions out there might suit your needs out of the box:
http://www.roseindia.net/opensource/freeproxyservers.php
You would then configure the software/devices that access websites (e.g., your browser) to point to that proxy, so that all HTTP communication passed through it.
Your proxy could then restrict access to whatever URL(s) you wanted to, based on whatever logic you wanted to code up.
If you wanted to get really fancy/secure and require folks to use the proxy (and not to choose to bypass it), you could do that, but that's probably more than you need to, given your question.
You could append entries to your hosts file using the Files class, as shown in this post: How to append text to an existing file in Java?.
This works on all platforms (yes, all of them: including Windows, Mac, Linux, Android, and more), and blocks access for all browsers, without the need for a proxy or special browser extensions (which can be deleted in most cases).
Here is some simple code to start you off. Feel free to edit it to fit your needs:
public void blockSite(String url) {
// Note that this code only works in Java 7+,
// refer to the above link about appending files for more info
// Get OS name
String OS = System.getProperty("os.name").toLowerCase();
// Use OS name to find correct location of hosts file
String hostsFile = "";
if ((OS.indexOf("win") >= 0)) {
// Doesn't work before Windows 2000
hostsFile = "C:\\Windows\\System32\\drivers\\etc\\hosts";
} else if ((OS.indexOf("mac") >= 0)) {
// Doesn't work before OS X 10.2
hostsFile = "etc/hosts";
} else if ((OS.indexOf("nux") >= 0)) {
hostsFile = "/etc/hosts";
} else {
// Handle error when platform is not Windows, Mac, or Linux
System.err.println("Sorry, but your OS doesn't support blocking.");
System.exit(0);
}
// Actually block site
Files.write(Paths.get(hostsFile),
("127.0.0.1 " + url).getBytes(),
StandardOpenOption.APPEND);
}
Imports for above method:
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.nio.file.StandardOpenOption;
Sample usage:
blockSite("www.example.com");
Note:
This needs to be run as an administrator (Windows) or using sudo (Mac, Linux).
This might not work for some platforms, as it was only tested on Ubuntu Linux.
P.S. If you're making parental control software, you should also look into blocking programs. Not all things you would want to block are on the Internet. Here is some simple code for that:
/**
Blocks programs.
#param programs - The array of process names.
#param timeout - The time between blocks, in milliseconds.
This parameter should not be set below 100, to avoid slowdown.
#author https://stackoverflow.com/users/5905216/h-a-sanger
*/
public void blockPrograms(int timeout, String...programs) throws IOException {
// Get OS name
String OS = System.getProperty("os.name").toLowerCase();
// Identify correct blocking command for OS
String command = "";
if ((OS.indexOf("win") >= 0)) {
command = "taskkill /f /im ";
} else if ((OS.indexOf("mac") >= 0) || (OS.indexOf("nux") >= 0)) {
command = "killall ";
} else {
// Handle error when platform is not Windows, Mac, or Linux
System.err.println("Sorry, but your OS doesn't support blocking.");
System.exit(0);
}
// Start blocking!
while(true) {
// Cycle through programs list
for(int i = 0; i < programs.length; i++) {
// Block program
Runtime.getRuntime().exec(command + programs[i]);
}
// Timeout
try { Thread.sleep(timeout); } catch(InterruptedException e) {}
}
}
Imports for above code:
import java.io.IOException;
Sample usage:
blockPrograms(100, "chrome", "firefox");
Again, let me note this was only tested on Ubuntu Linux.
Ok, I know that System.getProperty("os.name") will give me the name of the OS I'm running under, but that's not a lot of help. What I need to know is if the OS I'm running on is a 'Unix-like' OS, I don't care if it's HP-UX, AIX, Mac OS X or whatever.
From the list of possible os.name values it seems like a quick and dirty way of detecting a 'Unix-like' OS is checking if os.name does not contain "Windows". The false positives that will give me are OSes my code is very unlikely to encounter! Still, I'd love to know a better way if there is one.
Use the org.apache.commons.lang.SystemUtils utility class from Commons Lang, it has a nice IS_OS_UNIX constant. From the javadoc:
Is true if this is a POSIX compilant
system, as in any of AIX, HP-UX, Irix,
Linux, MacOSX, Solaris or SUN OS.
The field will return false if OS_NAME
is null.
And the test becomes:
if (SystemUtils.IS_OS_UNIX) {
...
}
Simple, effective, easy to read, no cryptic tricks.
I've used your scheme in production code on Windows XP, Vista, Win7, Mac OS 10.3 - 10.6 and a variety of Linux distros without an issue:
if (System.getProperty("os.name").startsWith("Windows")) {
// includes: Windows 2000, Windows 95, Windows 98, Windows NT, Windows Vista, Windows XP
} else {
// everything else
}
Essentially, detect Unix-like by not detecting Windows.
File.listRoots() will give you an array of the file system root directories.
If you are on a Unix-like system, then the array should contain a single entry "/" and on Windows systems you'll get something like ["C:", "D:", ...]
Edit: #chris_l: I totally forgot about mobile phones. Some digging turns up that Android returns a "/\0\0" - a slash followed by two null bytes (assumed to be a bug). Looks like we avoid false positives for the time being through luck and coincidence. Couldn't find good data on other phones, unfortunately.
It's probably not a good idea to run the same code on desktops and mobile phones regardless, but it is interesting to know. Looks like it comes down to needing to check for specific features instead of simply the system type.
Javadoc says: On UNIX systems the value of this
* field is '/'; on Microsoft Windows systems it is '\'.
System.out.println( File.separatorChar == '/' ? "Unix" : "Windows" );
System.getProperty("os.name"); is about the best you are going to get.
I agree with #Fuzzy in that I think the only way that Java intended you to be able to get that information was through the os.name property.
The only other things I can think of are:
Have a shell script or batch file wrapper to launch your Java app that passes in OS information using the -D argument to the JVM. Though given your description, this doesn't sound doable.
You could try to check for the existence of an OS-specific directory. For instance, you could assume the directory "/" will always exist on a Unix-like system, but not on Windows and do something like this:
if((new File("/")).exists())
{
System.out.println("I'm on a Unix system!");
}
Try to kick off a Unix-specific command line command like ls and check the return code. If it worked, you're on a Unix-like system, if not you're on Windows.
All of those solutions are really just hacks though and frankly I don't really feel all that great about any of them. You're unfortunately probably best off with your original thought. Fun, eh?
Use File.pathSeparator or File.separator. The first will return ";" in Windows and ":" in Unix. The second will return "\" in Windows and "/" in Unix.
You could try to execute the uname command - should be available on all unixoid systems.
package com.appspot.x19290;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
public class UnixCheck {
public static void main(String[] args) {
UnixCheck s = UnixCheck.S;
String isUnix = s.unix ? "is Unix" : "not Unix";
try {
System.out.println(isUnix + ", devnull: " + s.devnull.getPath());
} catch (NullPointerException e) {
System.out.println(isUnix + ", devnull: unknown");
}
}
public static final UnixCheck S = new UnixCheck();
public static final UnixCheck TEST = new UnixCheck(true);
public final boolean unix;
public final File devnull;
private UnixCheck() {
this(false);
}
private UnixCheck(boolean testing) {
String path;
path = testing ? "/<dev>/<no><such><null><device>" : "/dev/null";
File devnull = devnullOrNone(path);
if (devnull == null) {
this.unix = false;
path = testing ? "<no><such><null><device>" : "nul";
this.devnull = devnullOrNone(path);
} else {
this.unix = true;
this.devnull = devnull;
}
}
private static File devnullOrNone(String name) {
File file = new File(name);
if (file.isFile())
return null;
if (file.isDirectory())
return null;
try {
FileInputStream i = new FileInputStream(file);
try {
i.read();
} finally {
i.close();
}
} catch (IOException e) {
return null;
}
return file;
}
}