One way to run a process from a different directory to the working directory of your Java program is to change directory and then run the process in the same command line. You can do this by getting cmd.exe to run a command line such as cd some_directory && some_program.
The following example changes to a different directory and runs dir from there. Admittedly, I could just dir that directory without needing to cd to it, but this is only an example:
Copyimport java.io.*;
public class CmdTest {
public static void main(String[] args) throws Exception {
ProcessBuilder builder = new ProcessBuilder(
"cmd.exe", "/c", "cd \"C:\\Program Files\\Microsoft SQL Server\" && dir");
builder.redirectErrorStream(true);
Process p = builder.start();
BufferedReader r = new BufferedReader(new InputStreamReader(p.getInputStream()));
String line;
while (true) {
line = r.readLine();
if (line == null) { break; }
System.out.println(line);
}
}
}
Note also that I'm using a ProcessBuilder to run the command. Amongst other things, this allows me to redirect the process's standard error into its standard output, by calling redirectErrorStream(true). Doing so gives me only one stream to read from.
This gives me the following output on my machine:
C:\Users\Luke\StackOverflow>java CmdTest
Volume in drive C is Windows7
Volume Serial Number is D8F0-C934
Directory of C:\Program Files\Microsoft SQL Server
29/07/2011 11:03 <DIR> .
29/07/2011 11:03 <DIR> ..
21/01/2011 20:37 <DIR> 100
21/01/2011 20:35 <DIR> 80
21/01/2011 20:35 <DIR> 90
21/01/2011 20:39 <DIR> MSSQL10_50.SQLEXPRESS
0 File(s) 0 bytes
6 Dir(s) 209,496,424,448 bytes free
Videos
One way to run a process from a different directory to the working directory of your Java program is to change directory and then run the process in the same command line. You can do this by getting cmd.exe to run a command line such as cd some_directory && some_program.
The following example changes to a different directory and runs dir from there. Admittedly, I could just dir that directory without needing to cd to it, but this is only an example:
Copyimport java.io.*;
public class CmdTest {
public static void main(String[] args) throws Exception {
ProcessBuilder builder = new ProcessBuilder(
"cmd.exe", "/c", "cd \"C:\\Program Files\\Microsoft SQL Server\" && dir");
builder.redirectErrorStream(true);
Process p = builder.start();
BufferedReader r = new BufferedReader(new InputStreamReader(p.getInputStream()));
String line;
while (true) {
line = r.readLine();
if (line == null) { break; }
System.out.println(line);
}
}
}
Note also that I'm using a ProcessBuilder to run the command. Amongst other things, this allows me to redirect the process's standard error into its standard output, by calling redirectErrorStream(true). Doing so gives me only one stream to read from.
This gives me the following output on my machine:
C:\Users\Luke\StackOverflow>java CmdTest
Volume in drive C is Windows7
Volume Serial Number is D8F0-C934
Directory of C:\Program Files\Microsoft SQL Server
29/07/2011 11:03 <DIR> .
29/07/2011 11:03 <DIR> ..
21/01/2011 20:37 <DIR> 100
21/01/2011 20:35 <DIR> 80
21/01/2011 20:35 <DIR> 90
21/01/2011 20:39 <DIR> MSSQL10_50.SQLEXPRESS
0 File(s) 0 bytes
6 Dir(s) 209,496,424,448 bytes free
You can try this:-
CopyProcess p = Runtime.getRuntime().exec(command);
Just learning and am watching two different video tutorials on java. Is therre a list of commands/symbols that would allow me to play around when I am not following these courses/lessons? Only real "command" I know is the system.print one and a few others.
Source: javaindos.
Let's say your file is in C:\mywork\
Run Command Prompt
CopyC:\> cd \myworkThis makes C:\mywork the current directory.
CopyC:\mywork> dirThis displays the directory contents. You should see filenamehere.java among the files.
CopyC:\mywork> set path=%path%;C:\Program Files\Java\jdk1.5.0_09\binThis tells the system where to find JDK programs.
CopyC:\mywork> javac filenamehere.javaThis runs javac.exe, the compiler. You should see nothing but the next system prompt...
CopyC:\mywork> dirjavac has created the filenamehere.class file. You should see filenamehere.java and filenamehere.class among the files.
CopyC:\mywork> java filenamehereThis runs the Java interpreter. You should then see your program output.
If the system cannot find javac, check the set path command. If javac runs but you get errors, check your Java text. If the program compiles but you get an exception, check the spelling and capitalization in the file name and the class name and the java HelloWorld command. Java is case-sensitive!
To complete the answer :
The Java File
Copy
TheJavaFile.javaCompile the Java File to a *.class file
Copy
javac TheJavaFile.java- This will create a
TheJavaFile.classfile
- This will create a
Execution of the Java File
Copy
java TheJavaFileCreation of an executable
*.jarfileYou've got two options here -
With an external manifest file :
Create the manifest file say - MANIFEST.mf
The MANIFEST file is nothing but an explicit entry of the Main Class
jar -cvfm TheJavaFile.jar MANIFEST.mf TheJavaFile.class
Executable by Entry Point:
jar -cvfe TheJavaFile.jar <MainClass> TheJavaFile.class
To run the Jar File
Copy
java -jar TheJavaFile.jar