PROTOTYPE
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satin.common
Class SystemUtils

java.lang.Object
  |
  +--satin.common.SystemUtils

public class SystemUtils
extends java.lang.Object

Assorted system-level utilities.

Author:

Ed Stauff

Constructor Summary

SystemUtils()

Method Summary

static int	exec(java.lang.String command, java.lang.String[] envVars, java.io.File workingDir, java.lang.StringBuffer stdOut, java.lang.StringBuffer stdErr) Executes a system command and waits for it to complete.
static int	exec(java.lang.String command, java.lang.StringBuffer stdOut, java.lang.StringBuffer stdErr) Executes a system command and waits for it to complete.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SystemUtils

public SystemUtils()

Method Detail

exec

public static int exec(java.lang.String command,
                       java.lang.String[] envVars,
                       java.io.File workingDir,
                       java.lang.StringBuffer stdOut,
                       java.lang.StringBuffer stdErr)
                throws java.io.IOException,
                       java.lang.InterruptedException

Executes a system command and waits for it to complete. Note that this method does not support shell extensions, as the command is not automatically executed within a shell environment. Thus, things like pipes and I/O redirection cannot be used unless you explicitly invoke a shell as part of the command.

Example

 StringBuffer dirContents = new StringBuffer();
 StringBuffer error = new StringBuffer();
 if (0 != SystemUtils.exec("ls -l c:/temp", null, null, dirContents, error))
     throw new Error("ls failed: " + error);
 // On success, dirContents contains a directory listing of c:/temp.
 // On failure, error contains something like:
 //     "File or directory \"c:/temp\" not found"
 

Parameters:

command

the command to be executed.

envVars

an array of strings, each of which contains an environment variable setting of the form name=value. If this parameter is null, the subprocess (command) inherits its environment from the caller.

workingDir

the working directory for the command. If this parameter is null, the subprocess (command) inherits its working directory from the caller.

stdOut

the command's standard output will be appended to this buffer. Pass null if you don't want it.

stdErr

the command's standard error output will be appended to this buffer. Pass null if you don't want it.

Returns:

the exit code of the command, usually 0 on success.

exec

public static int exec(java.lang.String command,
                       java.lang.StringBuffer stdOut,
                       java.lang.StringBuffer stdErr)
                throws java.io.IOException,
                       java.lang.InterruptedException

Executes a system command and waits for it to complete. Note that this method does not support shell extensions, as the command is not automatically executed within a shell environment. Thus, things like pipes and I/O redirection cannot be used unless you explicitly invoke a shell as part of the command.

Example

 StringBuffer dirContents = new StringBuffer();
 StringBuffer error = new StringBuffer();
 if (0 != SystemUtils.exec("ls -l c:/temp", dirContents, error))
     throw new Error("ls failed: " + error);
 // On success, dirContents contains a directory listing of c:/temp.
 // On failure, error contains something like:
 //     "File or directory \"c:/temp\" not found"
 

Parameters:

command

the command to be executed.

stdOut

the command's standard output will be appended to this buffer. Pass null if you don't want it.

stdErr

the command's standard error output will be appended to this buffer. Pass null if you don't want it.

Returns:

the exit code of the command, usually 0 on success.

Revision History

9 July 2001 Ed Stauff - added overloaded exec that takes env and dir.