Package com.Ostermiller.util

Class ExecHelper

java.lang.Object
com.Ostermiller.util.ExecHelper
public final class ExecHelper extends Object
Convenience methods for executing non-Java processes. More information about this class is available from ostermiller.org.
Since:
ostermillerutils 1.06.00
Author:
Stephen Ostermiller https://ostermiller.org/contact.pl?regarding=Java+Utilities

  • Method Details

    • exec

      public static ExecHelper exec(String[] cmdarray) throws IOException
      Executes the specified command and arguments in a separate process, and waits for the process to finish.

      Output from the process is expected to be text in the system's default character set.

      No input is passed to the process on STDIN.

      Parameters:
      cmdarray - array containing the command to call and its arguments.
      Returns:
      The results of the execution in an ExecHelper object.
      Throws:
      SecurityException - if a security manager exists and its checkExec method doesn't allow creation of a sub process.
      IOException - - if an I/O error occurs
      NullPointerException - - if cmdarray is null
      IndexOutOfBoundsException - - if cmdarray is an empty array (has length 0).
      Since:
      ostermillerutils 1.06.00

    • exec

      public static ExecHelper exec(String[] cmdarray, String[] envp) throws IOException
      Executes the specified command and arguments in a separate process, and waits for the process to finish.

      Output from the process is expected to be text in the system's default character set.

      No input is passed to the process on STDIN.

      Parameters:
      cmdarray - array containing the command to call and its arguments.
      envp - array of strings, each element of which has environment variable settings in format name=value.
      Returns:
      The results of the execution in an ExecHelper object.
      Throws:
      SecurityException - if a security manager exists and its checkExec method doesn't allow creation of a sub process.
      IOException - - if an I/O error occurs
      NullPointerException - - if cmdarray is null
      IndexOutOfBoundsException - - if cmdarray is an empty array (has length 0).
      Since:
      ostermillerutils 1.06.00

    • exec

      public static ExecHelper exec(String[] cmdarray, String[] envp, File dir) throws IOException
      Executes the specified command and arguments in a separate process, and waits for the process to finish.

      Output from the process is expected to be text in the system's default character set.

      No input is passed to the process on STDIN.

      Parameters:
      cmdarray - array containing the command to call and its arguments.
      envp - array of strings, each element of which has environment variable settings in format name=value.
      dir - the working directory of the sub process, or null if the sub process should inherit the working directory of the current process.
      Returns:
      The results of the execution in an ExecHelper object.
      Throws:
      SecurityException - if a security manager exists and its checkExec method doesn't allow creation of a sub process.
      IOException - - if an I/O error occurs
      NullPointerException - - if cmdarray is null
      IndexOutOfBoundsException - - if cmdarray is an empty array (has length 0).
      Since:
      ostermillerutils 1.06.00

    • exec

      public static ExecHelper exec(String[] cmdarray, String charset) throws IOException
      Executes the specified command and arguments in a separate process, and waits for the process to finish.

      No input is passed to the process on STDIN.

      Parameters:
      cmdarray - array containing the command to call and its arguments.
      charset - Output from the executed command is expected to be in this character set.
      Returns:
      The results of the execution in an ExecHelper object.
      Throws:
      SecurityException - if a security manager exists and its checkExec method doesn't allow creation of a sub process.
      IOException - - if an I/O error occurs
      NullPointerException - - if cmdarray is null
      IndexOutOfBoundsException - - if cmdarray is an empty array (has length 0).
      Since:
      ostermillerutils 1.06.00

    • exec

      public static ExecHelper exec(String[] cmdarray, String[] envp, String charset) throws IOException
      Executes the specified command and arguments in a separate process, and waits for the process to finish.

      No input is passed to the process on STDIN.

      Parameters:
      cmdarray - array containing the command to call and its arguments.
      envp - array of strings, each element of which has environment variable settings in format name=value.
      charset - Output from the executed command is expected to be in this character set.
      Returns:
      The results of the execution in an ExecHelper object.
      Throws:
      SecurityException - if a security manager exists and its checkExec method doesn't allow creation of a sub process.
      IOException - - if an I/O error occurs
      NullPointerException - - if cmdarray is null
      IndexOutOfBoundsException - - if cmdarray is an empty array (has length 0).
      Since:
      ostermillerutils 1.06.00

    • exec

      public static ExecHelper exec(String[] cmdarray, String[] envp, File dir, String charset) throws IOException
      Executes the specified command and arguments in a separate process, and waits for the process to finish.

      No input is passed to the process on STDIN.

      Parameters:
      cmdarray - array containing the command to call and its arguments.
      envp - array of strings, each element of which has environment variable settings in format name=value.
      dir - the working directory of the sub process, or null if the sub process should inherit the working directory of the current process.
      charset - Output from the executed command is expected to be in this character set.
      Returns:
      The results of the execution in an ExecHelper object.
      Throws:
      SecurityException - if a security manager exists and its checkExec method doesn't allow creation of a sub process.
      IOException - - if an I/O error occurs
      NullPointerException - - if cmdarray is null
      IndexOutOfBoundsException - - if cmdarray is an empty array (has length 0).
      Since:
      ostermillerutils 1.06.00

    • execUsingShell

      public static ExecHelper execUsingShell(String command) throws IOException
      Executes the specified command using a shell. On windows uses cmd.exe or command.exe. On other platforms it uses /bin/sh.

      A shell should be used to execute commands when features such as file redirection, pipes, argument parsing are desired.

      Output from the process is expected to be text in the system's default character set.

      No input is passed to the process on STDIN.

      Parameters:
      command - String containing a command to be parsed by the shell and executed.
      Returns:
      The results of the execution in an ExecHelper object.
      Throws:
      SecurityException - if a security manager exists and its checkExec method doesn't allow creation of a sub process.
      IOException - - if an I/O error occurs
      NullPointerException - - if command is null
      Since:
      ostermillerutils 1.06.00

    • execUsingShell

      public static ExecHelper execUsingShell(String command, String charset) throws IOException
      Executes the specified command using a shell. On windows uses cmd.exe or command.exe. On other platforms it uses /bin/sh.

      A shell should be used to execute commands when features such as file redirection, pipes, argument parsing are desired.

      No input is passed to the process on STDIN.

      Parameters:
      command - String containing a command to be parsed by the shell and executed.
      charset - Output from the executed command is expected to be in this character set.
      Returns:
      The results of the execution in an ExecHelper object.
      Throws:
      SecurityException - if a security manager exists and its checkExec method doesn't allow creation of a sub process.
      IOException - - if an I/O error occurs
      NullPointerException - - if command is null
      Since:
      ostermillerutils 1.06.00

    • getOutput

      public String getOutput()
      Get the output of the job that ran.
      Returns:
      Everything the executed process wrote to its standard output as a String.
      Since:
      ostermillerutils 1.06.00

    • getError

      public String getError()
      Get the error output of the job that ran.
      Returns:
      Everything the executed process wrote to its standard error as a String.
      Since:
      ostermillerutils 1.06.00

    • getStatus

      public int getStatus()
      Get the status of the job that ran.
      Returns:
      exit status of the executed process, by convention, the value 0 indicates normal termination.
      Since:
      ostermillerutils 1.06.00