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Open git bash using processBuilder and execute command in it

Is it possible in java by using something like ProcessBuilder to open gitbash, write a command (for example git status) and output the results?
I can successfully open git bash by using the following code but i don't know how to write any commands in it.
String[] commands = {"cmd","/C","C:\\Users\\......\\Git\git-bash"};
ProcessBuilder builder = new ProcessBuilder(commands);
builder.redirectErrorStream(true);
Process process = builder.start();
StringBuilder sb = new StringBuilder();
BufferedReader br = null;
try
{
br=new BufferedReader(new InputStreamReader(process.getInputStream()));
String line = null;
while ((line = br.readLine()) != null) {
sb.append(line + System.getProperty("line.seperator"));
}
} finally {
br.close();
}
String outcome = get_output(process.getInputStream());
process.waitFor();
System.out.println("Process finished with outcome = " + outcome);

You just have to change the paths and the git command. But the git-bash output is printed on a separate .txt file because I couldn't read it in any other way.
public class GitBash {
public static final String path_bash = "C:/Program Files/Git/git-bash.exe";
// Create a file Output.txt where git-bash prints the results
public static final String path_file_output_git_bash =
"C:/Users/Utente/Documents/IntelliJ-DOC/IntelliJ_project/Prova/src/main/Git-bash/Output.txt";
public static void main(String[] args) {
// Path to your repository
String path_repository = "cd C:/Users/Utente/Documents/Repository-SVN-Git/Bookkeeper";
// Git command you want to run
String git_command = "git ls-files | grep .java | wc -l";
String command = path_repository + " && " + git_command + " > " + path_file_output_git_bash;
runCommand(command);
}
public static void runCommand(String command) {
try {
ProcessBuilder processBuilder = new ProcessBuilder();
processBuilder.command(path_bash, "-c", command);
Process process = processBuilder.start();
int exitVal = process.waitFor();
if (exitVal == 0) {
System.out.println(" --- Command run successfully");
System.out.println(" --- Output = " + readFileTxt());
} else {
System.out.println(" --- Command run unsuccessfully");
}
} catch (IOException | InterruptedException e) {
System.out.println(" --- Interruption in RunCommand: " + e);
// Restore interrupted state
Thread.currentThread().interrupt();
}
}
public static String readFileTxt() {
String data = null;
try {
File myObj = new File(path_file_output_git_bash);
Scanner myReader = new Scanner(myObj);
while (myReader.hasNextLine()) {
data = myReader.nextLine();
}
myReader.close();
} catch (FileNotFoundException e) {
System.out.println(" --- An error occurred");
e.printStackTrace();
}
return data;
}
}
}
--- EDIT 2021/03/26 ---
Answer without the needs of a .txt file : Read output git-bash with ProcessBuilder in Java

Lag from BufferedReader

I am having trouble finding the source of lag in my code. I believe I have narrowed the possible source down to this method.
Essentially I start a script, set it in a Process variable p, and grab the output from the script using a BufferedReader, and put it into an ArrayList.
Somehow I am getting lag when the script outputs (it outputs at a 5 minute interval)
Any ideas?
public void runCommand(String path)
{
if (SystemUtils.IS_OS_WINDOWS)
{
ProcessBuilder builder = new ProcessBuilder("cmd.exe", "/c", "cd " + path + " && " + this.getCommand());
builder.redirectErrorStream(true);
try
{
p = builder.start();
}
catch (IOException e)
{
e.printStackTrace();
}
}
else
{
try
{
String name = ManagementFactory.getRuntimeMXBean().getName();
String pid = name.substring(0, name.indexOf("#"));
p = Runtime.getRuntime().exec("./btrace.sh " + pid + " " + path + " " + this.getConfig().getPort());
}
catch (Exception e)
{
e.printStackTrace();
}
}
BufferedReader r = new BufferedReader(new InputStreamReader(p.getInputStream()));
String line;
try
{
// Print out everything that's happening.
while (true)
{
line = r.readLine();
if (line == null)
{
break;
}
if (this.isDebugEnabled)
{
System.out.println("[Script Output]: " + line);
}
lines.add(line);
}
r.close();
}
catch (IOException e)
{
e.printStackTrace();
}
}

Seems like I found the cause of lag.
After researching how ArrayLists resize, I realized it could be performance taxing and tried using a Linked list.
So far seems like the issue is fixed.
Thanks!

Using Java's process builder to call a C program

Trying to call a C program using Java's process builder but don't know what to call in the process builder call.
Process p = new ProcessBuilder("myCommand", "myArg").start();
For myCommand and myArg, what values would I replace it with for it to run a C Program? The program I want it to call is shown here:
calculator.c:
#include <stdio.h>
int main ()
{
int a = 4;
int b = 2;
int c = a + b;
printf("Result: %d \n", c);
}

If calculator.c has not been compiled yet, you will want to first compile it:
Process compile = new ProcessBuilder("gcc", "calculator.c").start();
Process execute = new ProcessBuilder("./a.out").start();
Any relevant compiler flags (e.g., -O or -o calculator) should be included in the arguments as well. If you do rename the executable, you'll want to change ./a.out with it.
A better way (in terms of having few hard-coded constants) would be to have some variables like:
String c_file = "calculator.c";
String output_exe = "calculator";
Process compile = new ProcessBuilder("gcc", "-o " + output_exe, c_file).start();
Process execute = new ProcessBuilder("./" + output_exe);
Lastly, you'll probably want to make sure each of your processes are exiting without error:
if (compile.getInputStream().read() == -1) {
// that means something was written to stderr, and you can do something like
System.out.error("ERROR!");
System.exit(-1);
}
As #VinayDandekar pointed out, you can also do this with exitValue.
if (compile.exitValue() == -1) {
// that means something was written to stderr, and you can do something like
System.out.error("ERROR!");
System.exit(-1);
}

At First Set Your Compiler Path On Environment Variable From Windows System Property Otherwise It will not work . Then Set Compile And Run Code
Compile Code: `
JFileChooser fileChooser=new JFileChooser();
if (fileChooser.showSaveDialog(compile.this) != JFileChooser.APPROVE_OPTION)
return;
File file = fileChooser.getSelectedFile();
try {
FileWriter out = new FileWriter(file);
textEditor.write(out);
out.close();
} catch (IOException e1) {
e1.printStackTrace();
}
String filepath = file.getPath();
String filepath2 = filepath.substring(0, filepath.lastIndexOf(File.separator));
System.out.println(filepath);
System.out.println(filepath2);
String name = file.getName();
String name2 = file.getName().substring(0, file.getName().lastIndexOf("."));
String folder = filepath2+"\\";
String exe = folder+name2+".exe";
System.out.println(exe);
ProcessBuilder pb=new ProcessBuilder();
try {
pb = new ProcessBuilder("cmd", "/C", "gcc " + "\"" + filepath2 + "\\" + name + "\"" + " -o \"" + name2+"\"");
pb = new ProcessBuilder("cmd", "/C", "g++ " + "\"" + filepath2 + "\\" + name + "\"" + " -o \"" + name2+"\"");
pb.directory(new File(filepath2));
Process p = pb.start();
p.waitFor();
int x = p.exitValue();
if (x == 0) {
area.setForeground(red);
area.setText(" == 0 error.. Compilation Finished");
} else {
BufferedReader r = new BufferedReader(new InputStreamReader(p.getErrorStream()));
//BufferedWriter rm=new BufferedWriter(new OutputStreamWriter(p.getOutputStream()));
String out;
area.setText("");
while ((out = r.readLine()) != null)
{
area.setForeground(RED);
area.append(out + System.getProperty("line.separator"));
}
}
} catch (Exception ex) {
ex.printStackTrace();
}
`
Run Code: `
JFileChooser fileChooser=new JFileChooser();
if (fileChooser.showSaveDialog(compile.this) != JFileChooser.APPROVE_OPTION)
return;
File file = fileChooser.getSelectedFile();
try {
FileWriter out = new FileWriter(file);
textEditor.write(out);
out.close();
} catch (IOException e1) {
e1.printStackTrace();
}
String filepath = file.getPath();
String filepath2 = filepath.substring(0, filepath.lastIndexOf(File.separator));
System.out.println(filepath);
System.out.println(filepath2);
String name = file.getName();
String name2 = file.getName().substring(0, file.getName().lastIndexOf("."));
String folder = filepath2+"\\";
String exe = folder+name2+".exe";
System.out.println(exe);
ProcessBuilder pb=new ProcessBuilder();
try {
pb = new ProcessBuilder("cmd", "/C", "gcc " + "\"" + filepath2 + "\\" + name + "\"" + " -o \"" + name2+"\"");
pb = new ProcessBuilder("cmd", "/C", "g++ " + "\"" + filepath2 + "\\" + name + "\"" + " -o \"" + name2+"\"");
pb.directory(new File(filepath2));
Process p = pb.start();
p.waitFor();
int x = p.exitValue();
int z=p.exitValue();
if (x == 0) {
Runtime rt = Runtime.getRuntime();
try {
String username = System.getProperty("user.name");
String c = "#echo off\n" + "\"" +
filepath2 + "\\" + name2 + ".exe\"\n" + "echo.\n" + "echo.\n" + "echo Process Terminated\n" +
"pause\n" +
"exit";
File dir = new File("C:\\Users\\" + username + "\\CodeEditor");
dir.mkdir();
try {
File file2 = new File("C:\\Users\\" + username + "\\CodeEditor" + "\\run.bat");
file2.createNewFile();
PrintWriter writer = new PrintWriter(file2);
writer.println(c);
writer.close();
Process p2 = Runtime.getRuntime().exec("cmd /c start run.bat", null, new File("C:\\Users\\" + username + "\\CodeEditor"));
} catch (Exception ex) {
}
} catch (Exception ex) {
}
} else {
JOptionPane.showMessageDialog(compile.this, "Compilation Error", "Error", JOptionPane.ERROR_MESSAGE);
}
} catch (Exception ex) {
ex.printStackTrace();
}
`
Done!!!

Runtime can be used to execute any command line instruction supported by OS.
Example below would be of help.
package com.test;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class CommandExec {
public static void main(String[] args) {
try {
Process pr = Runtime.getRuntime().exec("ls /etc");
BufferedReader read = new BufferedReader(new InputStreamReader(pr.getInputStream()));
String str = read.readLine();
while (str != null){
System.out.println(str);
str = read.readLine();
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}

Unix count line of file command - from java code

I'm trying to count the number of lines of a text file using a unix command from java code.
My code looks like:
String filePath = "/dir1/testFile.txt";
Runtime rt = Runtime.getRuntime();
Process p;
try {
System.out.println("No: of lines : ");
findLineCount = "cat " + filePath + " | wc -l";
p = rt.exec(findLineCount);
p.waitFor();
} catch (Exception e) {
//code
}
But, nothing is displayed in the console. When I execute the command directly, it works. What could be the issue in the above code?

I suggest you use a ProcessBuilder instead of Runtime.exec. You can also simplify your command by passing the filePath to wc. Please don't swallow Exception(s). Finally, you can use ProcessBuilder.inheritIO() (Sets the source and destination for subprocess standard I/O to be the same as those of the current Java process) like
String filePath = "/dir1/testFile.txt";
try {
System.out.println("No: of lines : ");
ProcessBuilder pb = new ProcessBuilder("wc", "-l", filePath);
pb.inheritIO();
Process p = pb.start();
p.waitFor();
} catch (Exception e) {
e.printStackTrace();
}
Of course, it's more efficient to count the lines in Java without spawning a new process. Perhaps like,
int count = 0;
String filePath = "/dir1/testFile.txt";
try (Scanner sc = new Scanner(new File(filePath));) {
while (sc.hasNextLine()) {
String line = sc.nextLine();
count++;
}
} catch (Exception e) {
e.printStackTrace();
}
System.out.printf("No: of lines : %d%n", count);

When I execute the command directly
I doubt you're execute it "directly". You're probably running it in a shell.
Your code should run that script in a shell too.
rt.exec(new String[]("bash", "-c", findLineCount});

This is how i printed number of lines
public static void main(String[] args) {
try {
Runtime run = Runtime.getRuntime();
String[] env = new String[] { "path=%PATH%;" + "your shell path " }; //path of cigwin bin or any similar application. this is needed only for windows
Process proc = run.exec(new String[] { "bash.exe", "-c", "wc -l < yourfile" }, env);
BufferedReader reader = new BufferedReader(new InputStreamReader(
proc.getInputStream()));
String s;
while ((s = reader.readLine()) != null) {
System.out.println("Number of lines " + s);
}
proc.waitFor();
int exitValue = proc.exitValue();
System.out.println("Status {}" + exitValue);
} catch (IOException | InterruptedException e) {
e.printStackTrace();
}
}

How to execute command line from Java with setting the variables

try {
String command = "java -Xms64m -Xmx512m -cp %mypath% com.app.GenericAxlTool -i " + ip + " -v 6.0 -a " + axlVer + " -d " + dbVer + " -u " + userName + " -p " + password + " -c sqlselect -f " + queryFile;
String[] envArr = {pathCmd};
System.out.println("Command is: " + command);
ProcessBuilder pb = new ProcessBuilder(command);
Map<String, String> env = pb.environment();
env.put("mypath", ".;lib/gatui.jar;lib/gat.jar;lib/swing-layout-1.0.jar;lib/smtp.jar;lib/AbsoluteLayout.jar;lib/axis.jar;lib/commons-discovery-0.2.jar;lib/jaxm-runtime.jar;lib/jaxrpc.jar;lib/saaj-api.jar;lib/saaj-impl.jar;lib/activation.jar;lib/JSAP-2.1.jar;lib/SNMP4J.jar;lib/mailapi.jar;lib/jtapi.jar;lib/remotehands.jar;lib/conftransfer.jar;lib/jtapi.jar;;lib/devicedashboard.jar;lib/pcdb.jar;lib/lic.jar;lib/poi-3.8-20120326.jar");
pb.directory(new File(curDir));
Process p = pb.start();
//Runtime runtime = Runtime.getRuntime();
//Process p = runtime.exec(command, envArr, new File(curDir));
InputStream is = p.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
String line;
while ((line = br.readLine()) != null) {
System.out.println(line);
}
p.waitFor();
System.out.println("Done with: " + queryFile);
} catch (IOException ex) {
ex.printStackTrace();
} catch (InterruptedException ex) {
ex.printStackTrace();
} finally {
return false;
}
The above code results in IOException and secondly, I dont get any output from the stream as well. Here is folder structure.
MainDir
|
--lib
--src
|
--com.query.Exec
|
javafile.java

I dont know what are you trying to do with your code, but to execute commandlines you can simply use
Runtime.getRuntime().exec(command)
where command is a string representing the command you want to run.