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Process does not exit when launched from Java

I am launching WebTorrent-CLI from within my Java application as a separate process. I am using zt-exec for managing the process. When WebTorrent is launched with the following command, it is supposed to exit after the file at given index (value of --select) has been downloaded.
"D:\downloadmanager\node\webtorrent.cmd" download "magnet:?xt=urn:btih:08ada5a7a6183aae1e09d831df6748d566095a10&dn=Sintel" --select 0 --out "D://nf/"
As expected, webtorrent-cli does exit after downloading 0th file when the command above is used to launch it from command line. But when I try the same from within my Java app, it completely ignores the --select option and continues downloading other files in the torrent.
Basically, when launched as a process from Java, webtorrent ignores all the options set (--select, --out or whatever). I should mention that there is nothing wrong with the library because recently I've tried replacing it with commons-exec and that solved nothing. Also, to make sure that the right command is passed while starting the process, I'm printing the command right before calling executor.start(). The command above is copied from the output retrieved from printing the command before the process starts.
This is how the process is started:
#Override
public synchronized void start() throws IOException {
if (mWasDownloadStarted || mWasDownloadFinished) return;
mExec.getCommand().listIterator().forEachRemaining(s -> {
System.out.print(s + " ");
});
mExec.start();
setProcessId();
mWasDownloadStarted = true;
mWasDownloadStopped = false;
}
This is how the command is prepared:
private String buildCommand() {
List <String> command = new ArrayList<>();
command.add("\"" + mManager.mWTLocation + "\"");
command.add("download");
command.add("\"" + mManager.mMagnetUrl + "\"");
if (mManager.mFileIndex >= 0) {
command.add("--select " + mManager.mFileIndex);
}
if (mManager.mSaveTo != null) {
command.add("--out \"" + mManager.mSaveTo + "\"");
}
mManager.mExec.command(command);
String cmdStr = "";
for (String s : command) {
cmdStr = cmdStr.concat(s + " ");
}
return cmdStr.trim();
}
What might be wrong?

Okay, so I was able to fix this issue.
The / character following the path specified as value of --out was causing the problem. In order to fix this, I added a line in node_modules/webtorrent-cli/bin/cmd.js to print the arguments passed to webtorrent:
console.log(process.argv)
With the /, output of this line was something like the following:
[ 'D:\\downloadmanager\\node\\node.exe',
'D:\\downloadmanager\\node\\node_modules\\webtorrent-cli\\bin\\cmd.js',
'download',
'magnet:?xt=urn:btih:08ada5a7a6183aae1e09d831df6748d566095a10&dn=Sintel',
'--select',
'0',
'--out',
'D:\\nf"' ]
Note the " that is included in the path after D:\\nf. When / is removed from the path, the quote disappears and webtorrent behaves as expected.
I doubt that this is a bug in webtorrent. I think zt-exec (or maybe I) was doing something stupid.
Somewhat unrelated, but I think I should also mention that I had to enclose every value for each option with quotes, even the index, to get rid of other nasty errors (e.g.: Error 87, the parameter is incorrect)

How to take mysql database backup by using java? [duplicate]

This question already has answers here:
backup mysql database java code
(3 answers)
Closed 9 years ago.
I am trying to take mysql database backup by using following code but I am getting exception like below when I run the program. Plz can anyone plz help out to solve this problem.
Java Code:
String path = "D:/databasbac.sql";
String username = "root";
String password = "";
String dbname = "ranjith";
String executeCmd = "<Path to MySQL>/bin/mysqldump -u " + username + " -p" + password + " --add-drop-database -B " + dbname + " -r " + path;
Process runtimeProcess;
try {
// System.out.println(executeCmd);//this out put works in mysql shell
runtimeProcess = Runtime.getRuntime().exec(new String[] { "cmd.exe", "/c", executeCmd });
// runtimeProcess = Runtime.getRuntime().exec(executeCmd);
int processComplete = runtimeProcess.waitFor();
if (processComplete == 0) {
System.out.println("Backup created successfully");
} else {
System.out.println("Could not create the backup");
}
} catch (Exception ex) {
ex.printStackTrace();
}

There are at least two issues:
Provide a full path to mysqldump.exe (e.g. C:\Program Files\MySQL\bin\mysqldump.exe)
-p parameter without a password value forces mysqldump to prompt for it. And you don't want it since you running it in a batch mode. Therefore either provide a password -p"your password" or better (and more secure) use an option file to avoid giving the password on the command line. Read more on this End-User Guidelines for Password Security

reading java property value with spaces into one variable

Hello my problem is as follows:
i have a property fiel with a startconfig for external program to run from java:
# Standardauswahl falls keine PlayerType übergeben wurden
Default = 1
# Liste der gültigen PlayerTypes
PlayerTypes = Human,MCTS,TMM,Random,Value
StartConfig = \"C:\\Program Files\\Java\\jdk1.7.0_13\\bin\\javaw.exe\" -Dlog4j.configuration=file:///C:/Users/djdeejay/git/myGit/com.djdeejay.cowTrade.client.standaloneplayer.application/bin/log4j.xml -Dfile.encoding=Cp1252 -classpath [..... some parameter deleted.....] 0.0-RC1.jar;C:\\Users\\djdeejay\\git\\myGit\\de.thWildau.cowTrade.server\\lib\\slf4j-api-1.5.2.jar;C:\\Users\\djdeejay\\git\\myGit\\de.thWildau.cowTrade.server\\lib\\slf4j-log4j12-1.5.2.jar;C:\\Users\\djdeejay\\git\\myGit\\de.thWildau.cowTrade.server\\lib\\log4j-1.2.16.jar com.djdeejay.cowTrade.client.standaloneplayer.application.RandomPlayerApplication %1 %2 %3
when i load the properties as follows
cmd = this.serverSettings.getPlayerTypeSetting("StartConfig");
#Override
public String getPlayerTypeSetting(String key) {
return this.startPlayerTypeSettingsProp.getProperty(key);
}
java cutting startconfig after the first space:
Cannot run program """C:\Program" when its in doublequotes or Cannot run program ""C:\Program":
i have tried several variants with "", with escaping and so on nothing gives my needed result
how do i config getproperty to read until EOL?
cheers

As discussed in the comments, the getProperty call is alright. But the usage as a single string in Runtime.getRuntime().exec(cmd) uses the default whitespace Tokenizer to split the string into command and argument.
To do this yourself, first split the string manually and then pass it to Runtime#exec:
String startCmdLine = this.serverSettings.getPlayerTypeSetting("StartConfig");
int cmdEndPos = startCmdLine.indexOf("javaw.exe") + "javaw.exe".length();
String cmd = startCmdLine.substring(0, cmdEndPos);
String args = startCmdLine.substring(cmdEndPos);
Runtime.getRuntime().exec(new String[]{ cmd, args });
Though I really advise you to take advantage of the JAVA_HOME environment variable if you just want to start a known java binary. That way you can reduce that to a set of parameters in the property file.

Try replacing your spaces with: "\u0020"

Use this:
StringEscapeUtils.escapeXml(String input);
See doc here

Scala - Fails to execute a process through terminal in a particular scenario

I'm using graphviz to generate graphs based on the messages passed in a scala program.
To invoke the graphviz application from inside the scala program, I'm using the exec() method (similar to Java). It successfully executed the command and created the graph when I used the below code snippet:
var cmd: String = "dot -Tpng Graph.dot -o Graph.png"
var run: Runtime = Runtime.getRuntime() ;
var pr: Process = run.exec(cmd) ;
However It fails to execute after changing the path of the input and output files (I just included a directory inside which the input file and output file resides as shown below)
def main(args: Array[String]): Unit = {
var DirectoryName: String = "Logs"
var GraphFileName: String = DirectoryName + File.separator + "Graph.dot"
val GraphFileObj: File = new File(GraphFileName)
// var cmd: String = "dot -Tpng Graph.dot -o Graph.png"
var cmd: String = "dot -Tpng \"" + GraphFileObj.getAbsolutePath + "\" -o \"" + DirectoryName + File.separator + "Graph.png\"" ;
println(cmd)
var run: Runtime = Runtime.getRuntime() ;
var pr: Process = run.exec(cmd) ;
}
The same command when executed through terminal gives proper output. Can you please help me to find what I'm missing?

exec is not a shell...e.g. quoting won't work as you expect, and thus your path (which may contain spaces, etc) will not be processed as you expect. The command will be broken apart using StringTokenizer, and your literal quotes will be...well..literal.
Use the form of exec that takes an array instead, so you can tokenize the command correctly.
val args = Array[String]("dot", "-Tpng", GraphFileObj.getAbsolutePath, ...);
run.exec(args)

Does php urlencode the same with java urlencode?

In PHP：
php -r "echo urlencode('["IM"]'); "
The result is %5BIM%5D
But in java
String text = URLEncoder.encode('["IM"]',"UTF-8");
System.out.println("text" + text);
The result is text%5B%22IM%22%5D
What's the different between these two functions? How can I implement a java code to complete the same function of php?

String text = URLEncoder.encode('[IM]',"UTF-8");
System.out.println("text" + text);
gives %5BIM%5D
echo urlencode('["IM"]');
gives %5B%22IM%22%5D
echo urlencode('[IM]');
gives %5BIM%5D
echo urlencode('[\"IM\"]');
gives %5B%5C%22IM%5C%22%5D

php -r "echo urlencode('["IM"]'); "
The result is %5BIM%5D because the function urlencode is actually only taking the string [IM] as its input. while in java
String text = URLEncoder.encode('["IM"]',"UTF-8");
The string being passed is actually: ["IM"] which generates the value %22 which is encode-string for " the quote mark.

try to escape internal qoutes
php -r "echo urlencode('[\"IM\"]'); "