Calling Scripts from Java through SFTP Connection - java

I am newbie for calling scripts from Java through the SFTP connection.
So far, I managed to find the code snippets below
Process p = Runtime.getRuntime().exec("cmd /c start Hello.bat");
p.waitFor();
Here is sample for Hello.bat
#echo off
echo "Hello World"
However, I couldn't see the output in cmd window eve there were no errors.(seem like Hello.bat file location is not right?)
My actual and final script include copying, reading, archiving, delete and return code for success or fail.
What type of script with the above methods will be fine and I hope some one will advise me for the right direction with working sample.
Thanks and best regards

just Runtime.getRuntime().exec("cmd /c start Hello.bat") works for me. Also see How do I run a batch file from my Java Application?
Make a small change in batch file to keep command prompt open
#echo off
echo "Hello World"
PAUSE
so your java code is fine you just need to modify batch file to keep command prompt open when program is run successfully.

Related

How to run batch file with parameters in java?

I have created a jar file called test.jar under C:\jars. I have JAR file under the same location named run.bat and it contains the below code -
#echo off
set exec_path=C:\jars java -cp %exec_path%/test.jar; com.mycomp.myapp.MyProgram "%1"%*
#echo on
It is running successfully from command prompt with parameters.
Now I would like to run it from another JAVA program.
Please suggest.
Thanks!
I've encountered this issue before. The answer is that you have to run cmd.exe or bash or whatever shell you've got, then feed in the command to that process via the process input/output streams.
Process p = Runtime.getRuntime().exec("cmd");
p.getOutputStream().write("mybatch.bat\n");

launching java program via batch and php,

php and batch files.
So i'm executing batch files through php
I have no issues launching the batch.
$str = exec('C:\WINDOWS\system32\cmd.exe /c START C:\MInecraft\_restart.bat');
However the issue im having is getting the batch file to work currectly. When the batch is run, it executes this code
taskkill /IM java.exe /F
java -Xmx1024M -jar craftbukkit.jar -o true
batch file successfully runs the taskkill command when launched with php, however it will not run the next line. When ran manually it launches fine, (bear in mind that the cmd.exe does not exit it stays open with this code)
Any ideas on how i can get this to launch from php?
Maybe the reason is the same as given at Error Executing Batch file of BlazeDS, the java executable is not found by Windows on running the batch file from within PHP script.
The current working directory or the directories listed in environment variable PATH can be different when the batch file is executed from within the PHP script in comparison to running the batch file manually.
Do you have ever tried to specify java.exe with full path in double quotes in the batch file?
You could also add at top of the batch file the commands
dir /w
PATH
to see which directory is the current directory and which directories are listed in environment variable PATH on execution of the batch file from within PHP script.
Forgot to post back here, I specified java through windows path command rather than the batch. The problem is because the java process takes the cmd and turns it into a console, it never finishes the batch file. So, the php never returns and continues the code unless the batch is force ably closed on the server.
pclose(popen("start /B C:\MInecraft\_restart.bat &", "r")); die();
I ended up using this command, which i believe makes it launch the batch and not wait for a reply. Just carry on with the php.
Thanks for your kind reply. I did initially try launching java in multiple ways.

How to execute shell script and save in text file command through java in linux

I m using Linux.
I want to call a small executable application from my java command line which is called "wmic". It needs an input query. Output are stored in text file in the specific directory.
When I use the command in Linux Terminal
echo "Hello World" >> /home/kannan/hello.txt
the output is stored in hello.txt file.
but when i call this command from java
Process p = Runtime.getRuntime().exec("echo \"Hello World\" >> /home/kannan/hello1.txt");
the output is not created any hello1.txt file
Please any one help me.
Thanks in Advance.
Use a ProcessBuilder. It makes it easy to redirect output of a command to file as shown below:
new ProcessBuilder("echo", "hello").redirectOutput(new File("output.txt")).start();
If you want to append to the output file:
new ProcessBuilder("echo", "hello").redirectOutput(Redirect.appendTo(new File("output.txt"))).start();
What you are executing is bash command (echo). Your java program do not work as bash interpreter
To execute any script which requires bash or shell scripting features, your need to execute that interpreter
To solve your problem you can follow below steps
1. Write your string into temp .sh file. Lets call it temp.sh
2. execute below using Runtime.getRuntime().exec
Process p = Runtime.getRuntime().exec("bash temp.sh");
bash will try to execute any command in temp.sh

How do I open a .bat containing a GUI in a java program in Linux?

everyone. I'm quite new here so please be tolerant if I make any mistakes.
I have a .bat file containing a command line to open up a .jar file that contains a program that has a GUI in it. The only line that's in the .bat file is:
java -jar "NewServer.jar"
I've been trying to use Runtime() to get this to run, but most the instructions I find to open a .bat file in a java program are for Windows. I'm currently using Fedora 12 (don't tell me to upgrade, I can't) if that makes a difference and programming using Eclipse. I also found this ProcessBuilder thing, but I couldn't get it to work so unless you have very explicit directions on how to use it, please don't include it in your answer. I would much rather use Runtime. It looked simpler.
Here's my code to test using Runtime in a java program. I'm hoping that if I can get this to work, I can get it to work in my real program.
import java.io.IOException;
public class testbat {
public static void main(String[] args) {
Process proc = null;
try {
proc = Runtime.getRuntime().exec("./ myServer.bat");
} catch (IOException e) {
e.printStackTrace();
}
System.out.println("Cool");
}
The last line is just there for me to see if the program actually ran in case the GUI doesn't open. Also, I've already tried many combinations of things to include in the area after ".exec". I've tried using a path like "~/user/workspace/ProjectServer/dist/myServer.bat" to no avail.
I also already know that .bat files are for windows, but I'm able to execute it in linux, so I don't know if that makes a difference. I also tried using a .sh file the same way and it didn't work.
Please bear in mind that I'm not that great at Java, but I had to use it for this particular program, so if your answers could be really descriptive that would be awesome.
Just take that line out of the bat file, and run it. Yo're making it too hard.
$ java -jar "NewServer.jar"
will work. The quotes aren't necessary, so
$ java -jar NewServer.jar
will work as well. If you want to have the equivalent of your bat file, create a file named, say, run_newserver containing that line. Change its mode to executable:
$ cat > run_newserver
java -jar NewServer.jar
^D
$ chmod a+x run_newserver
$ ./run_newserver
Ideally, since you shouldn't have scripts without comments, do this. In your favorite editor, create a file run_newserver containing
#!/usr/bin/env bash
java -jar NewServer.jar
and chmod that. The line with #! -- often called a "shebang line" -- is UNIX magic that lets you say what interpreter you want. The program env in usr/bin finds your program and runs it (needed because different systems put bash in different directories.)
You could even put explanatory comments in the file too.
I'm a little unclear why you want to use Runtime#exec to run it at all -- it seems you'll just need a shell script to start that program.
Why are you using Java to run a Batch file, that in turn runs a Java program? Why have Batch in the loop at all? Just put the jar in your classpath and call it directly.
Batch (.bat) files are only for Windows environment. So, Try using shell script
Process proc = Runtime.getRuntime().exec("myServer.sh");
Just open up terminal and do this
vi /dir/to/exec/exec.sh
tap "i" and write this
#!/bin/sh
java -jar "NewServer.jar"
or if you want to run it in the background
#!/bin/sh
java -jar "NewServer.jar" & > /tmp/JavaServer.log
hit esc and type ":wq" and you have saved the file.
type this into the terminal
chmod +x /dir/to/exec/exec.sh
this give executable privileges and then you should run the file like
sh /dir/to/exec/exec.sh
Process is only initialized by your first call. You need to run:
proc.waitfor();
to get it to actually run your app.

Permission denied error in Java for chmod command

I have an executable file (ffmpeg) that I'm trying to run with a Java program on a Mac. I used the Java program to send the command chmod 777 /path/to/ffmpeg, but when I try to run ffmpeg, I get the following error:
java.io.IOException: Cannot run program "/Users/james/WalkTheHall/ffmpeg": error=13, Permission denied
But when I run chmod 777 /path/to/ffmpeg from Terminal on my own before opening the Java application, the command to ffmpeg will run just fine in the Java program.
Is there a difference between calling chmod from within the Java program and calling it on my own? Why will it not work? Thank you!
I just had the same problem in my code.
i solved this by add waitFor after exec. The "chmod" process is not finished when next command is executed. the code may look like:
p = Runtime.getRuntime.exec("chmod 777 xxx");
p.waitFor();
Runtime.getRuntime.exec("./xxx");
I'd guess that chmod is a shell command, not an executable. Try running chmod through your shell. See more details here: Want to invoke a linux shell command from Java
Yes, there is a difference. When you run the command from the terminal, it is you who is performing the action, and thus it is performed using your credentials. The Java application is running the command using the Java application's permissions. This is to prevent an application from running and then making dangerous, unwanted changes to the file system. Perhaps someone else can elaborate and give guidance to a workaround for this.
I am currently working on a project that also makes use of FFMpeg on OSX. I store FFMpeg in the JAR and extract it and set executable on use as you seem to be doing. This is what I do, and it seems to work.
public static void setExecutable(File file, boolean executable)
{
Process p = Runtime.getRuntime().exec(new String[] {
"chmod",
"u"+(executable?'+':'-')+"x",
file.getAbsolutePath(),
});
// do stuff to make sure p finishes & capture output
}
The code is GPL, so feel free to check it out. Its not the nicest codebase, and even the FFMpeg stuff is perhaps overly complex, but it works.
Source is viewable at http://korsakow.net
These two files in particular might be interesting for you
FFMpegEncoderOSX.java
FileUtil.java
Try this:
File commandFile = new File("myFile.txt");
commandFile.setExecutable(true);
Process p = Runtime.getRuntime.exec(commandFile.getAbsoluteFile());
to start an program on OSX you need this:
Runtime.getRuntime().exec("chmod 777 "+path); //in order to execute it
Runtime.getRuntime().exec(path); //execute it
Runtime.getRuntime().exec("chmod 744 "+path); //undo every change
path should be the path to the exc of the program, for example:
AppStore -> Applications/App\ Store.app/Contents/MacOS/App\ Store

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