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Why wont this .jar file run when I try to start it on C#? [closed]

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I'm very new to the coding space and was wondering if someone could help me start a .jar file. BTW This is using C#. My issue is this wont run the file. I got it to work with .txt files though, so I'm just a bit confused.
private void button1_Click(object sender, EventArgs e)
{
Process.Start("java" , "server.jar");
}

In short, for the answer, add -jar right before the JAR file name.
The accepted answer is not 100% correct for several reasons: it does not recognize whitespace-delimited and whitespace-containing arguments, and may mess up with quote characters that must be passed (therefore properly escaped) to the delegated Java app. In short, do not use Arguments if the string is not known to be a constant (having spaces will require manual escaping anyway), but merely prefer ArgumentList that handles each argument properly.
Here is an example Java application to deal with command line arguments:
public final class SayHello {
private SayHello() {}
public static void main(final String... names) {
for ( final String name : names ) {
System.out.printf("hello %s!\n", name);
}
}
}
The manifest for the JAR file:
Manifest-Version: 1.0
Main-Class: SayHello
Making a JAR file out of it is simple:
javac SayHello.java
jar cfm SayHello.jar MANIFEST.MF SayHello.class
Example of use:
java -jar SayHello.jar 'John Doe' Anonymous
that gives:
hello John Doe!
hello Anonymous!
Now, an example C# program that passes the -jar argument to the java process so that it recognizes the given file as a JAR file and demonstrates what can go wrong with Arguments if passed as a string.
<Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>net5.0</TargetFramework>
</PropertyGroup>
</Project>
using System.Diagnostics;
public static class SayHello {
public static void Main() {
// interprets 3 names: John, Doe, Anonymous (wrong)
RunJavaJarBadly1("SayHello.jar", "John Doe Anonymous");
// interprets 1 name: John Doe Anonymous (wrong)
RunJavaJarBadly2("SayHello.jar", "John Doe Anonymous");
// interprets 2 names: John Doe, Anonymous (correct, but bad: requires the first name to be quoted at the call-site)
RunJavaJarBadly1("SayHello.jar", "\"John Doe\" Anonymous");
// interprets 1 name: "John Doe" Anonymous (wrong: interprets everything as a single name)
RunJavaJarBadly2("SayHello.jar", "\"John Doe\" Anonymous");
// interprets 2 names, no ambiguous call, each name is recognized properly, does not require quoting at the call site
RunJavaJar("SayHello.jar", "John Doe", "Anonymous");
}
private static void RunJavaJarBadly1(string jarPath, string argumentsFortheJarFile) {
var process = new Process();
process.StartInfo.FileName = "java";
process.StartInfo.Arguments = #"-jar "+ jarPath +" " + argumentsFortheJarFile;
process.Start();
process.WaitForExit();
}
private static void RunJavaJarBadly2(string jarPath, string jarArgs) {
var process = new Process();
process.StartInfo = new ProcessStartInfo("java") {
ArgumentList = { "-jar", jarPath, jarArgs }
};
process.Start();
process.WaitForExit();
}
private static void RunJavaJar(string jarPath, params string[] jarArgs) {
var process = new Process();
process.StartInfo = new ProcessStartInfo("java") {
ArgumentList = { "-jar", jarPath }
};
foreach ( var jarArg in jarArgs ) {
process.StartInfo.ArgumentList.Add(jarArg);
}
process.Start();
process.WaitForExit();
}
}
The code above produces (no legend in the output, but added for explanation):
hello John! \_ #1/1: incorrect, the space is ignored
hello Doe! /
hello Anonymous! -- #1/2: correct, no spaces in-between
hello John Doe Anonymous! -- #2/1|2: incorrect
hello John Doe! -- #3/1: correct, but requires the call site to escape the argument
hello Anonymous! -- #3/2: correct, no need to escape, thanks to no spaces
hello "John Doe" Anonymous! -- #4/1|2: incorrect, similar to #2/1|2
hello John Doe! -- #5/1: correct, let the framework do its job
hello Anonymous! -- #5/2: correct, let the framework do its job

In order to get it to work, the file name needs to be "java" and contain the file location in the arguments.
System.Diagnostics.Process clientProcess = new Process();
clientProcess.StartInfo.FileName = "java";
clientProcess.StartInfo.Arguments = #"-jar "+ jarPath +" " + argumentsFortheJarFile;
clientProcess.Start();
clientProcess.WaitForExit();
int code = clientProcess.ExitCode;
Taken from similar question here
Optional way using ArgumentList:
System.Diagnostics.Process clientProcess = new Process();
var info = new System.Diagnostics.ProcessStartInfo("java.exe")
{
ArgumentList = {
"-jar",
jarPath,
jarArgs
}
};
info.FileName = "java";
clientProcess.StartInfo = info;
clientProcess.Start();
clientProcess.WaitForExit();
int code = clientProcess.ExitCode;

Here are some options for you to check out.
Also similar question with a working result: here
Paraphrasing from links:
In order to get it to work, the file name needs to be "java" and contain the file location in the arguments.
System.Diagnostics.Process clientProcess = new Process();
clientProcess.StartInfo.FileName = "java";
clientProcess.StartInfo.Arguments = #"-jar "+ jarPath +" " + argumentsFortheJarFile;
clientProcess.Start();
clientProcess.WaitForExit();
int code = clientProcess.ExitCode;

how to get an output python from java input?

actually, i'm new in python. Here, i want to get an output from class of python. but here, i input String from java.
here's the java code:
String word;
Scanner in = new Scanner(System.in);
System.out.println("input: ");
word = in.nextLine();
TryinPythonToJavaAgain ie = new TryinPythonToJavaAgain();
ie.execfile("~\\hello.py");
PyInstance hello = ie.createClass("Hello", word);
hello.invoke("run");
python code:
class Hello:
def __init__(self, abc):
self.abc = abc
def run(self):
print(self.abc)
if i input : "hello"
i have an error like this:
input:
hello
Exception in thread "main" Traceback (most recent call last):
File "", line 1, in
NameError: name 'hello' is not defined
Java Result: 1
and if i input >2 word (e.g "hello world"), i have an error like this:
input:
hello world
Exception in thread "main" SyntaxError: ("no viable alternative at input 'world'", ('', 1, 12, 'Hello(hello world)\n'))
Java Result: 1
what should i fix in this code? thanks

If the code in your createClass method looks anything like this ...
PyInstance createClass( final String className, final String opts )
{
return (PyInstance) this.interpreter.eval(className + "(" + opts + ")");
}
... then I think you need to add quotes round the opts variable. The code above is from here which works since "None" gets turned into this.interpreter.eval(className(None)) which is valid whereas yours becomes this.interpreter.eval(className(hello world)) which isn't.
I've not tried it, but this.interpreter.eval(className("hello world")) would seem more likely to work.

Static Java function imported with rJava doesn't work with tm_map()

I've prepared a class with a static method in Java 6, which I've exported to a JAR file:
package pl.poznan.put.stemutil;
public class Stemmer {
public static String stemText(String text) {
Set<String> c = new HashSet<String>();
...
return StringUtils.join(c, " ");
}
}
I import it to R with following code:
require(rJava)
.jinit("java/stem-util.jar")
stem = J("pl.poznan.put.stemutil.Stemmer")$stemText
Then, when I call it directly it works, e.g:
> stem("płotkami")
[1] "płotek płotka"
But when I'll try to use it with tm_map() function, something goes wrong:
> vc = VCorpus(vs, readerControl = list(language = "pl"))
> vc[[1]]
<<PlainTextDocument (metadata: 7)>>
mirki mirkówny zaczynam wolne jutra ( ͡° ͜ʖ ͡°) #pijzwykopem #piwozlidla
> vc = tm_map(vc, stem)
Komunikat ostrzegawczy:
In mclapply(content(x), FUN, ...) :
all scheduled cores encountered errors in user code
> vc[[1]]
[1] "Error in FUN(X[[1L]], ...) : \n Sorry, parameter type `NA' is ambiguous or not supported.\n"
attr(,"class")
[1] "try-error"
attr(,"condition")
<simpleError in FUN(X[[1L]], ...): Sorry, parameter type `NA' is ambiguous or not supported.>
What am I doing incorrectly?

Finally adding mc.cores parameter has worked for me. However, It's more a workaround, than a proper solution.
vc = tm_map(vc, content_transformer(stem), mc.cores=1)

Passing query from php to java

i em trying to fetch some query from an url and then pass them to a java program for further execution. The problem i am facing is that my php code is calling my java program but is not passing the values.
till now i have worked on these codes,
PHP PROGRAM:
<?php
$phonecode= $_GET['phonecode'];
$keyword= $_GET['keyword'];
$location= $_GET['location'];
exec("C:\Users\Abc\Documents\NetBeansProjects\JavaApplication11\src\javaapplication11\main.java -jar jar/name.jar hello" . $phonecode . ' ' . $keyword . ' ' . $location, $output);
print_r($output);
?>
JAVA PROGRAM:
public class Main
{
public static void main(String args[])
{
try
{
String phonecode = args[];
System.out.println(args[]);
System.out.println(phonecode);// i have only tried to print phonecode for now
}
catch(Exception e)
{
System.out.println(e);
}
}
}

Ok, a couple of issues with the Java code you've posted, here's a working version of what you posted:
class Main
{
public static void main(String[] args)//String[] args, not String args[]
{
if (args.length == 0)
{//check to see if we received arguments
System.out.println("No arguments");
return;
}
if ( args.length < 3)
{//and make sure that there are enough args to continue
System.out.println("To few arguments");
return;
}
try
{//this try-catch block can be left out
String phonecode = args[0];//first arg
String keyword = args[1];//second
String location = args[2];//third
//print out the values
System.out.print("Phonecode: ");
System.out.println(phonecode);
System.out.print("keyword: ");
System.out.println(keyword);
System.out.print("location: ");
System.out.println(location);
}
catch(Exception e)
{
System.out.println(e.getMessage());//get the exception MESSAGE
}
}
}
Now, save that as a .java file, and compile it, it should churn out a Main.class file. I compiled it from the command-line:
javac main.java
I don't have netbeans installed, but I suspect the .class file will be written to a different directory, something like:
C:\Users\Abc\Documents\NetBeansProjects\JavaApplication11\bin\javaapplication11\Main.class
// note the BIN
Then, to execute, you need to run the java command, and pass it the path to this Main.class file, leaving out the .class extension. Thus, we end up with:
java /path/to/Main 123 keywrd loc
Should result in the output:
Phonecode: 123
keyword: keywrd
location: loc
In your PHP code:
exec('java /path/to/Main '.escapeshellarg($phonecode). ' '.escapeshellarg($keyword).' '.escapeshellarg($location), $output, $status);
if ($status === 0)
{//always check exit code, 0 indicates success
var_dump($output);
}
else
exit('Error: java exec failed: '.$status);
There are a couple of other issues, too: like $phonecode = $_GET['phonecode']; doesn't check if that $_GET param exists. If it doesn't your code will emit notices. To fix:
$phonecode = isset($_GET['phonecode']) ? $_GET['phonecode'] : '';
Other niggles include: the backslash is a special char in strings, it is used in escape sequences: \n is a newline char. PHP can deal with the *NIX directory separator /, even on windows. Use that, or escape the backslashes (C:\\Users\\Abc\\ and so on).
A file that only contains PHP code doesn't require the closing ?> tag. In fact: it is recommended you leave it out.

your java code should look like
public static void main (String[] args) {
for (String s: args) {
System.out.println(s);
}
}
Note String[] args, not String args[]
Also on PHP side in exec you need space between string hello, and variable $phonecode if you want those to be looked as a 2 separate arguments.

JavaScript ScriptEngine isn't working within Google App Engine for Java (GAE/J)

I am having an issue where I always get a 0 value returned when I try to use the ScriptEngine eval. By using Logger, I was able to determine that there are NullPointerExceptions being generated. After further inspection, it appears that GAE doesn't always return a valid script engine (if ever), because it throws an exception when you try to use it.
My code looks like:
public double myEval(String JsFormulaStr ) {
double solutionValue = 0;
ScriptEngineManager mgr = new ScriptEngineManager();
ScriptEngine eng = mgr.getEngineByName("JavaScript");
if(eng == null) { // Added this block of code to prevent java.lang.NullPointerException...
log.severe("Unable to get Script Engine." );
return 0;
}
try {
Object jsResults = eng.eval(JsFormulaStr);
solutionValue = Double.parseDouble(jsResults.toString());
return solutionValue;
} catch(Exception e) {
log.severe("[ERROR] in getCalculatedSolution_FromJS_ToDouble()::\n\t" +
"Formula String is: " + JsFormulaStr + "\n\t" + e);
return 0;
}
}
Everything works fine if I run it locally as a WebApp (Both in Eclipse & Netbeans. And within Tomcat & Glassfish 4.0).
Some of the strings which I tried to eval:
62.0 / 100
0.0 * 352.0
(0 - 428) * 1000
(0 - 597) * 1000
73.0 / 100
NOTE: The 0's or 0.0's are from other evaluations which have failed in previous calls. Since this function returns 0 on error.
According to Google's JRE Class Whitelist, the ScriptEngineManager and ScriptEngine classes are allowed. So I don't understand why it isn't working as expected.
Any suggestions?
Thanks in advance,
Randy

I've hit the same problem. Although the classes are whitelisted, it seems like their functionality is limited on App Engine. The code works fine on your local machine but fails when deployed to App Engine as there aren't any script engines available (hence the NullPointerException).
Luckily, you can do the same thing using the Rhino engine.
Note: this example builds on that given by Harsha R in https://stackoverflow.com/a/19828128/578821
Download the Rhino Jar and add js.jar to your classpath (you only need js-14.jar if you're using Java 1.4).
/* Example 1: Running a JavaScript function (taken from examples) */
String script = "function abc(x,y) {return x+y;}";
Context context = Context.enter();
try {
ScriptableObject scope = context.initStandardObjects();
Scriptable that = context.newObject(scope);
Function fct = context.compileFunction(scope, script, "script", 1, null);
Object result = fct.call(context, scope, that, new Object[] { 2, 3 });
System.out.println(Context.jsToJava(result, int.class));
}
finally {
Context.exit();
}
/* Example 2: execute a JavaScript statement */
script = "3 + 2 * (4*5)";
context = Context.enter();
try{
Scriptable scope = context.initStandardObjects();
Object result = context.evaluateString(scope, script, "<cmd>", 1, null);
System.out.println(result);
}
finally{
Context.exit();
}