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Run python file for AWS CloudFormation using JAVA

I want to run a python file that can run AWS CloudFormation template using JAVA.
I am passing python file in JAVA code.
When I run the JAVA code it pauses at the following state:
compile-single:
run-single:
If i run the Python file from terminal it works perfectly.
Java Code:
private void RunPythonActionPerformed(java.awt.event.ActionEvent evt) {
String pythonScriptPath = "path to python file";
String[] cmd = new String[2];
cmd[0] = "python"; // check version of installed python: python -V
cmd[1] = pythonScriptPath;
// create runtime to execute external command
Runtime rt = Runtime.getRuntime();
Process pr = null;
try {
pr = rt.exec(cmd);
// retrieve output from python script
} catch (IOException ex) {
Logger.getLogger(Page2.class.getName()).log(Level.SEVERE, null, ex);
}
BufferedReader bfr = new BufferedReader(new InputStreamReader(pr.getInputStream()));
String line = "";
try {
while((line = bfr.readLine()) != null) {
// display each output line form python script
System.out.println(line);
}
// TODO add your handling code here:
} catch (IOException ex) {
Logger.getLogger(Page2.class.getName()).log(Level.SEVERE, null, ex);
}
}

Provide path to your source file at <complete path to your python source file>
Copying working code for you. For me output is Python 3.6.5
package com.samples;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class ProcessBuilderSample {
public static void main(String [] args) throws IOException {
RunPythonActionPerformed();
}
private static void RunPythonActionPerformed() throws IOException {
String pythonScriptPath = "python -V";
Process p = Runtime.getRuntime().exec(pythonScriptPath);
BufferedReader bfr = new BufferedReader(new InputStreamReader(p.getInputStream()));
String line = "";
try {
while((line = bfr.readLine()) != null) {
// display each output line form python script
System.out.println(line);
}
// TODO add your handling code here:
} catch (IOException ex) {
}
}
}

Run a shell file in java

In Java you can call a shell file like this:
public class Shell {
private static Shell rootShell = null;
private final Process proc;
private final OutputStreamWriter writer;
private Shell(String cmd) throws IOException {
this.proc = new ProcessBuilder(cmd).redirectErrorStream(true).start();
this.writer = new OutputStreamWriter(this.proc.getOutputStream(), "UTF-8");
}
public void cmd(String command) {
try {
writer.write(command+'\n');
writer.flush();
} catch (IOException e) { }
}
public void close() {
try {
if (writer != null) {
writer.close();
if(proc != null) {
proc.destroy();
}
}
} catch (IOException ignore) {}
}
public static void exec(String command) {
Shell.get().cmd(command);
}
public static Shell get() {
if (Shell.rootShell == null) {
while (Shell.rootShell == null) {
try {
Shell.rootShell = new Shell("su"); //Open with Root Privileges
} catch (IOException e) { }
}
}
return Shell.rootShell;
}
}
Shell.exec("echo " + bt.getLevel() + " > "+ flashfile);
right.
but I have a shell which giving an argument after executing it.
how can I pass that argument? I don't want user type anything to run this shell file. in another word, I want to fully automate a shell file.

If you want to automate a shell file with a Java programme, this can be done. You could even pipe a series of commands to this programme saved in a file and executing these as a batch.
You can execute commands batches of commands from like this:
java -cp experiments-1.0-SNAPSHOT.jar ConsoleReader < commands.txt
commands.txt is a file with a series of commands:
cmd /k date
cmd /k dir
netstat
ipconfig
Or you can with the same programme allow the user to execute commands on the command line.
Below you can find a sample programme which you can compile and be run in the above described manner.
What does it do?
It hooks a java.util.Scanner to the console input and consumes each line.
Then it spawns two threads which listen to the error and input streams and write out either to stderr or stdin.
Empty lines on the console are ignored
If you type "read " it will execute the commands on that file.
Source:
public class ConsoleReader {
public static void main(String[] args) throws IOException, DatatypeConfigurationException {
try(Scanner scanner = new Scanner(new BufferedInputStream(System.in), "UTF-8")) {
readFromScanner(scanner);
}
}
private static final Pattern FILE_INPUT_PAT = Pattern.compile("read\\s*([^\\s]+)");
private static void readFromScanner(Scanner scanner) {
while (scanner.hasNextLine()) {
try {
String command = scanner.nextLine();
if(command != null && !command.trim().isEmpty()) {
command = command.trim();
if("exit".equals(command)) {
break; // exit shell
}
else if(command.startsWith("read")) { // read from file whilst in the shell.
readFile(command);
}
else {
Process p = Runtime.getRuntime().exec(command);
Thread stdout = readFromStream(p.getInputStream(), System.out, "in");
Thread stderr = readFromStream(p.getErrorStream(), System.err, "err");
stdout.join(200);
stderr.join(200);
}
}
}
catch(Exception e) {
Logger.getLogger("ConsoleReader").log(Level.SEVERE, String.format("Failed to execute command %s", e));
}
}
}
private static void readFile(String command) throws FileNotFoundException {
Matcher m = FILE_INPUT_PAT.matcher(command);
if(m.matches()) {
String file = m.group(1);
File f = new File(file);
if (f.exists()) {
try (Scanner subScanner = new Scanner(f)) {
readFromScanner(subScanner);
}
}
}
else {
System.err.printf("Oops, could not find '%s'%n", command);
}
}
private static Thread readFromStream(InputStream stdin, PrintStream out, String name) throws IOException {
Thread thread = new Thread(() -> {
try (BufferedReader in = new BufferedReader(new InputStreamReader(stdin))) {
String line;
while ((line = in.readLine()) != null) {
out.println(line);
}
} catch (IOException e) {
Logger.getLogger("ConsoleReader").log(Level.SEVERE, "Failed to read from stream.", e);
}
}, name);
thread.setDaemon(true);
thread.start();
return thread;
}
}

Runtime.getRuntime().exec("src/[FILE LOCATION]");
I think this is the command you're looking for. Let me know if it works!

How to read Android properties with Java

I use 'adb shell getprop' in the terminal.
What interfaces can I use in Android JAVA to get the same information?
I have tried several things like:
Properties sysProps = System.getProperties();
But I don't think these are the same properties I am looking for? Specifically, I want to find values that will return similar to the following:
adb shell getprop | grep dolby
The shell 'grep dolby' command returns this:
[audio.dolby.ds2.enabled]: [true]
[dolby.audio.sink.info]: [headset]
[dolby.ds.dialogenhancer.state]: [on]
[dolby.ds.graphiceq.state]: [off]
[dolby.ds.hpvirtualizer.state]: [off]
[dolby.ds.intelligenteq.preset]: [Off]
[dolby.ds.intelligenteq.state]: [off]
[dolby.ds.platform]: [qcom]
[dolby.ds.profile.name]: [Movie]
[dolby.ds.spkvirtualizer.state]: [off]
[dolby.ds.state]: [off]
[dolby.ds.volumeleveler.state]: [on]
But I want to access this information in Android JAVA code.
Any ideas?

I cleaned up TMont's solution and made it more generic (added parameter for propertyName):
import android.util.Log;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class SystemProperties {
private static String GETPROP_EXECUTABLE_PATH = "/system/bin/getprop";
private static String TAG = "MyApp";
public static String read(String propName) {
Process process = null;
BufferedReader bufferedReader = null;
try {
process = new ProcessBuilder().command(GETPROP_EXECUTABLE_PATH, propName).redirectErrorStream(true).start();
bufferedReader = new BufferedReader(new InputStreamReader(process.getInputStream()));
String line = bufferedReader.readLine();
if (line == null){
line = ""; //prop not set
}
Log.i(TAG,"read System Property: " + propName + "=" + line);
return line;
} catch (Exception e) {
Log.e(TAG,"Failed to read System Property " + propName,e);
return "";
} finally{
if (bufferedReader != null){
try {
bufferedReader.close();
} catch (IOException e) {}
}
if (process != null){
process.destroy();
}
}
}
}

In case someone wanted to know my solution... with George's help I ended up using this:
private String propReader() {
Process process = null;
try {
process = new ProcessBuilder().command("/system/bin/getprop")
.redirectErrorStream(true).start();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
InputStream in = process.getInputStream();
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(process.getInputStream()));
StringBuilder log = new StringBuilder();
String line;
try {
while ((line = bufferedReader.readLine()) != null) {
if (line.contains("dolby"))
log.append(line + "\n");
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println(in);
process.destroy();
return log.toString();
}

There actually is a system side implementation of the getprop call. It is called Systemproperties.get() and can be found here. For users, that work on system code inside the AOSP, or do want to take the risk of using reflect, this is the way to go.

System.getProperties() does not return the same properties as getprop.
To get getprop properties, try executing getprop using Runtime.exec() and reading its standard output.

For getting the system properties using reflection, try the below code snippet with your required property name.
public String getSerialNumber() {
String serialNumber;
try {
Class<?> c = Class.forName("android.os.SystemProperties");
Method get = c.getMethod("get", String.class);
serialNumber = (String) get.invoke(c, "ril.serialnumber");
if (serialNumber.equals(""))
serialNumber = (String) get.invoke(c, "ro.serialno");
if (serialNumber.equals(""))
serialNumber = (String) get.invoke(c, "ro.boot.serialno");
if (serialNumber.equals(""))
serialNumber = (String) get.invoke(c, "ro.kernel.androidboot.serialno");
// If none of the methods above worked
if (serialNumber.equals("")) {
serialNumber = Build.SERIAL;
}
} catch (Exception e) {
e.printStackTrace();
serialNumber = "";
}
return serialNumber;
}

Detecting terminal command errors in Java

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();
}
}

How to run Linux commands in Java?

I want to create diff of two files. I tried searching for code in Java that does it, but didnt find any simple code/ utility code for this. Hence, I thought if I can somehow run linux diff/sdiff command from my java code and make it return a file that stores the diff then it would be great.
Suppose there are two files fileA and fileB. I should be able to store their diff in a file called fileDiff through my java code. Then fetching data from fileDiff would be no big deal.

You can use java.lang.Runtime.exec to run simple code. This gives you back a Process and you can read its standard output directly without having to temporarily store the output on disk.
For example, here's a complete program that will showcase how to do it:
import java.io.BufferedReader;
import java.io.InputStreamReader;
public class testprog {
public static void main(String args[]) {
String s;
Process p;
try {
p = Runtime.getRuntime().exec("ls -aF");
BufferedReader br = new BufferedReader(
new InputStreamReader(p.getInputStream()));
while ((s = br.readLine()) != null)
System.out.println("line: " + s);
p.waitFor();
System.out.println ("exit: " + p.exitValue());
p.destroy();
} catch (Exception e) {}
}
}
When compiled and run, it outputs:
line: ./
line: ../
line: .classpath*
line: .project*
line: bin/
line: src/
exit: 0
as expected.
You can also get the error stream for the process standard error, and output stream for the process standard input, confusingly enough. In this context, the input and output are reversed since it's input from the process to this one (i.e., the standard output of the process).
If you want to merge the process standard output and error from Java (as opposed to using 2>&1 in the actual command), you should look into ProcessBuilder.

You can also write a shell script file and invoke that file from the java code. as shown below
{
Process proc = Runtime.getRuntime().exec("./your_script.sh");
proc.waitFor();
}
Write the linux commands in the script file, once the execution is over you can read the diff file in Java.
The advantage with this approach is you can change the commands with out changing java code.

You need not store the diff in a 3rd file and then read from in. Instead you make use of the Runtime.exec
Process p = Runtime.getRuntime().exec("diff fileA fileB");
BufferedReader stdInput = new BufferedReader(new InputStreamReader(p.getInputStream()));
while ((s = stdInput.readLine()) != null) {
System.out.println(s);
}

try to use unix4j. it s about a library in java to run linux command. for instance if you got a command like:
cat test.txt | grep "Tuesday" | sed "s/kilogram/kg/g" | sort
in this program will become:
Unix4j.cat("test.txt").grep("Tuesday").sed("s/kilogram/kg/g").sort();

You can call run-time commands from java for both Windows and Linux.
import java.io.*;
public class Test{
public static void main(String[] args)
{
try
{
Process process = Runtime.getRuntime().exec("pwd"); // for Linux
//Process process = Runtime.getRuntime().exec("cmd /c dir"); //for Windows
process.waitFor();
BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream()));
String line;
while ((line=reader.readLine())!=null)
{
System.out.println(line);
}
}
catch(Exception e)
{
System.out.println(e);
}
finally
{
process.destroy();
}
}
}
Hope it Helps.. :)

Runtime run = Runtime.getRuntime();
//The best possible I found is to construct a command which you want to execute
//as a string and use that in exec. If the batch file takes command line arguments
//the command can be constructed a array of strings and pass the array as input to
//the exec method. The command can also be passed externally as input to the method.
Process p = null;
String cmd = "ls";
try {
p = run.exec(cmd);
p.getErrorStream();
p.waitFor();
}
catch (IOException e) {
e.printStackTrace();
System.out.println("ERROR.RUNNING.CMD");
}finally{
p.destroy();
}

The suggested solutions could be optimized using commons.io, handling the error stream, and using Exceptions. I would suggest to wrap like this for use in Java 8 or later:
public static List<String> execute(final String command) throws ExecutionFailedException, InterruptedException, IOException {
try {
return execute(command, 0, null, false);
} catch (ExecutionTimeoutException e) { return null; } /* Impossible case! */
}
public static List<String> execute(final String command, final long timeout, final TimeUnit timeUnit) throws ExecutionFailedException, ExecutionTimeoutException, InterruptedException, IOException {
return execute(command, 0, null, true);
}
public static List<String> execute(final String command, final long timeout, final TimeUnit timeUnit, boolean destroyOnTimeout) throws ExecutionFailedException, ExecutionTimeoutException, InterruptedException, IOException {
Process process = new ProcessBuilder().command("bash", "-c", command).start();
if(timeUnit != null) {
if(process.waitFor(timeout, timeUnit)) {
if(process.exitValue() == 0) {
return IOUtils.readLines(process.getInputStream(), StandardCharsets.UTF_8);
} else {
throw new ExecutionFailedException("Execution failed: " + command, process.exitValue(), IOUtils.readLines(process.getInputStream(), StandardCharsets.UTF_8));
}
} else {
if(destroyOnTimeout) process.destroy();
throw new ExecutionTimeoutException("Execution timed out: " + command);
}
} else {
if(process.waitFor() == 0) {
return IOUtils.readLines(process.getInputStream(), StandardCharsets.UTF_8);
} else {
throw new ExecutionFailedException("Execution failed: " + command, process.exitValue(), IOUtils.readLines(process.getInputStream(), StandardCharsets.UTF_8));
}
}
}
public static class ExecutionFailedException extends Exception {
private static final long serialVersionUID = 1951044996696304510L;
private final int exitCode;
private final List<String> errorOutput;
public ExecutionFailedException(final String message, final int exitCode, final List<String> errorOutput) {
super(message);
this.exitCode = exitCode;
this.errorOutput = errorOutput;
}
public int getExitCode() {
return this.exitCode;
}
public List<String> getErrorOutput() {
return this.errorOutput;
}
}
public static class ExecutionTimeoutException extends Exception {
private static final long serialVersionUID = 4428595769718054862L;
public ExecutionTimeoutException(final String message) {
super(message);
}
}

if the opening in windows
try {
//chm file address
String chmFile = System.getProperty("user.dir") + "/chm/sample.chm";
Desktop.getDesktop().open(new File(chmFile));
} catch (IOException ex) {
Logger.getLogger(Frame.class.getName()).log(Level.SEVERE, null, ex);
{
JOptionPane.showMessageDialog(null, "Terjadi Kesalahan", "Error", JOptionPane.WARNING_MESSAGE);
}
}

ProcessBuilder processBuilder = new ProcessBuilder();
// -- Linux --
// Run a shell command
processBuilder.command("bash", "-c", "ls /home/kk/");
// Run a shell script
//processBuilder.command("path/to/hello.sh");
// -- Windows --
// Run a command
//processBuilder.command("cmd.exe", "/c", "dir C:\\Users\\kk");
// Run a bat file
//processBuilder.command("C:\\Users\\kk\\hello.bat");
try {
Process process = processBuilder.start();
StringBuilder output = new StringBuilder();
BufferedReader reader = new BufferedReader(
new InputStreamReader(process.getInputStream()));
String line;
while ((line = reader.readLine()) != null) {
output.append(line + "\n");
}
int exitVal = process.waitFor();
if (exitVal == 0) {
System.out.println("Success!");
System.out.println(output);
System.exit(0);
} else {
//abnormal...
}
} catch (IOException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
}