Package Torello.Java

Class MSDOS

  • All Implemented Interfaces:
    java.lang.Cloneable
    public class MSDOS
extends OSCommands
implements java.lang.Cloneable
    This Class Extends OSCommands:
    Class OSCommands is the parent class for all classes which invoke Operating-System Processes using the Java-Standard java.lang.Process Object-Utility.

    OSCommands has several constructors inherited by this class which allow a user to configure this class for sending its output in any number of ways to Appendable instances / loggers of your choice. Read this class documentation about invoking a constructor using any number of log-configurations, for sending text-output to any neccessary destination.

    All Methods Return OSResponse:
    In addition to real-time process-output printing, this class will collect any all text sent to Standard-Output and Error-Output and save the String-data for return to the user. All Operating-System calls in this class (which are all invoked by these methods, below) will always return an instance of OSResponse.

    Class OSResponse also contains the field response, which signals what the OS-Process' return-value was. Operating-Systems, generally, return a '0' to indicate the process ran to completion without errors, and some other value to signal an error occurred.

    java.lang.Process Extras
    java.lang.Process provides several additional features that allow a user to redirect output, and collect-input to and from any number of additional sources, among others. Torello.Java takes advantage of these with class OSExtras. Copious documentation about this class is provided, explaining these features.

    To specialize an Operating-System call with an OSExtras instance, just call this class' setOSExtras(...) method, with any neccessary configurations.
    A great tool for invoking commands to an MS-DOS operating-system. Allows a straight-forward way to make simple command-line / operating-system calls to an Microsoft DOS terminal.

    WORA:
    In its inception, Java made the "Write Once, Run Anywhere" (WORA) pledge. The methods in this class are not in any way "Java-ized" versions of the Operating System Calls. Rather, they are just wrappers around java.lang.Process allowing a user to BOTH make Operating System calls easily AND to efficiently retrieve the generated text-output produced by the calls.

    The bulk-work of the classes in this JAR Library were written and tested in a UNIX environment. While everything else in the Java HTML JAR Library is, indeed, O/S Independent (adhering to 'WORA'), this class and all classes which extend OSCommands are not! In fact, they are highly O/S dependent. The methods in these classes are actually just a set of hooks into native Operating System calls.

    This does mean that any invocation of these methods, when running in some other Operating System Environment, will just throw exceptions.


    Wild Cards:
    The behavior of expanding an '*' or '?' is another somewhat Operating-System Dependent phenomenon. It may be the case that Wild-Cards are expanded by the Operating-System, before the call. In such scenarios, when Java makes a call to the O/S it must have expanded its Wild-Cards.

    Logging Output:
    This class inherits OSCommands, which exports four Appendable Configuration-Fields for collecting the output of the Operating-System Commands in this class. These fields are all nullable, meaning that when one of these fields are assigned null, no exceptions will throw. Instead, that particular logging feature will simply be deactivated.

    The table below explains what java.lang.Process Output-Text is collected by each of the public Configurable-Fields exported by (parent-class) OSCommands. All four of these are declared public & non-final, so they are easily configured - just assign them to any java.lang.Appendable of your choosing!.

    Each of these four configuration-fields will log a slightly different variant of the java.lang.Process object's output-text.
    Configurable FieldLogged-Text Description / Type
    outputAppendable The text that is sent to this log is the unified text produced by reading the java.lang.Process instance's Standard-Output Stream, and its Error-Output Stream. Both are sent, as best as possible, in the order that such text is received by the reader threads.
    commandStrAppendable This log simply collects the actual command being issued to the Process-Object. The text sent to this log is nothing more than the joined text of input-command's String[]-Array.
    standardOutput This log collects all text that is sent to Standard-Output when a command is executed.
    errorOutput This log collects all text that is sent to Error-Output when a command is executed.

    Both Command & Output:
    One common trick, in Java HTML, is to provide the same Appendable to both outputAppendable and commandStrAppendable, which allows for printing a command as it is being executed, and then subsequently, all of its output.

    In the two examples below, an instance of this class is built such that BOTH the command as a String AND the process' output are logged directly to the exact same Appendable. Here, the most commonly used Appendable of all, java.lang.System.out, is configured. Note that these two examples are identical, and (slightly) different ways to perform the exact same configurations: 

    // Use a constructor to build an instance of this class.
// Both the Process-Output and the Command-as-a-String are printed to System.out

MSDOS dos = new MSDOS(System.out, System.out, null, null);



    // Again - System.out is assigned to both "outputAppendable" and "commandStrAppendable"
// The code here is functionally identical to the code in the previous example.

MSDOS dos = new MSDOS();
dos.outputAppendable      = System.out;
dos.commandStrAppendable  = System.out;

    Appendable Help-Reminder: The following table provides a small reminder & description for several of the common ways to provide a Java Appendable to any method (or field) which accepts an Appendable type. This table is re-printed in a few locations throughout the Java-HTML Library where Appendable's are accepted.


    This expects an implementation of Java's java.lang.Appendable interface which allows for a wide range of options when logging intermediate messages.
    Class or Interface Instance Use & Purpose
    'System.out' Sends text to the standard-out terminal
    Torello.Java.StorageWriter Sends text to System.out, and saves it, internally.
    FileWriter, PrintWriter, StringWriter General purpose java text-output classes
    FileOutputStream, PrintStream More general-purpose java text-output classes

    Checked IOException:
    The Appendable interface requires that the Checked-Exception IOException be caught when using its append(...) methods.
    See Also:
    OSCommands, OSResponse


    • Constructor Detail

      • MSDOS

        🡇  ⇈  ⮫ 🗕  🗗  🗖 
        public MSDOS()
        This constructor assigns default values to all of the output logging Appendable's.

        Note that all of them are assigned 'null' - meaing their output will not be logged - except for the primary output Appendable field. this.outputAppendable. This field is assigned System.out, meaning that all text output by a process will be sent to the terminal window.
        Code:
        Exact Constructor Body:
         super();

      • MSDOS

        🡅  🡇  ⇈  ⮫ 🗕  🗗  🗖 
        public MSDOS​(java.lang.Appendable outputAppendable)
        This constructor allows a user to assign an instance Appendable to: appendable.

        The first collects all text-output generated by the processes and prints it using the Appendable's printing methods. This includes text generated for BOTH Standard-Output AND Error-Output. This text is collected in real time as it is output by the underlying process.

        Assigning null: Any of this class Appendable's may be assigned null. When an Appendable is assigned null, it is simply ignored. NullPointerException will not throw, and any output text that would be appended, isn't appended.
        Parameters:
        outputAppendable - This parameter's reference is assigned directly to the OSCommands field: appendable. To clearly understand the use of this field, please review the documentation linked for that field. To summarize, the java.lang.Appendable that is synonymously named appendable simply collects all output text generated by a processes as it executes, and sends it to the reference's append(...) method. This text will include that sent to BOTH Standard-Output AND text sent to Error-Output. The text that is printed is transmitted in the order it is received from the reader-threads that read the underlying process' text-pipes.

        By default this parameter is assigned System.out. When this default value is used, it means that as the process executes, any and all text it prints is sent to the UNIX or MS-DOS Operating System Terminal Window.

        This field may be assigned null, and when so it is just ignored. Assigning null to appendable. will not produce a NullPointerException.
        See Also:
        OSCommands.outputAppendable
        Code:
        Exact Constructor Body:
         super(outputAppendable);

      • MSDOS

        🡅  🡇  ⇈  ⮫ 🗕  🗗  🗖 
        public MSDOS​(java.lang.Appendable outputAppendable,
             java.lang.Appendable commandStrAppendable,
             java.lang.Appendable standardOutput,
             java.lang.Appendable errorOutput)
        Constructor that allows for assigning all four text-collecting Appendable's. Please review the documentation for each of these fields to understand better how these Appendable's may be used. There are links in the See-Also section, below.

        Assigning null: Any of this class Appendable's may be assigned null. When an Appendable is assigned null, it is simply ignored. NullPointerException will not throw, and any output text that would be appended, isn't appended.
        Parameters:
        outputAppendable - This parameter's reference is assigned directly to the OSCommands field: appendable. To clearly understand the use of this field, please review the documentation linked for that field. To summarize, the java.lang.Appendable that is synonymously named appendable simply collects all output text generated by a processes as it executes, and sends it to the reference's append(...) method. This text will include that sent to BOTH Standard-Output AND text sent to Error-Output. The text that is printed is transmitted in the order it is received from the reader-threads that read the underlying process' text-pipes.

        By default this parameter is assigned System.out. When this default value is used, it means that as the process executes, any and all text it prints is sent to the UNIX or MS-DOS Operating System Terminal Window.

        This field may be assigned null, and when so it is just ignored. Assigning null to appendable. will not produce a NullPointerException.
        commandStrAppendable - This java.lang.Appendable allows for yet another output mechanism when executing operating system commands. The sole purpose of this Appendable is to print the process command, itself, as a Java String - exactly as it was issued to the operating system.

        This allows a type of "Monitor Log" to store all commands being issued to the Operating-System, without having to include the full-text output that those process calls have produced. The value passed to this parameter is assigned to the OSCommands field named printCmdAppendable.

        This parameter may be null, and if it is, no such output will be generated.
        standardOutput - This Appendable is assigned to the internal OSCommands field: standardOutput. This Appendabe, as the name hopefully implies, allows a user to collect any / all text sent by the process to Standard-Output.

        Please review the documentation for that field to better understand it's use. Also, keep in mind that null may be passed to this parameter, and if / when it is the corresponding Appendable field will simply be ignored during the process execution.
        errorOutput - This Appendable is assigned to the internal OSCommands field: errorOutput. This Appendabe, as the name hopefully implies, allows a user to collect any / all text sent by the process to Error-Output.

        Please review the documentation for that field to better understand it's use. Also, keep in mind that null may be passed to this parameter, and if / when it is the corresponding Appendable field will simply be ignored during the process execution.
        See Also:
        OSCommands.outputAppendable, OSCommands.commandStrAppendable, OSCommands.standardOutput, OSCommands.errorOutput
        Code:
        Exact Constructor Body:
         super(outputAppendable, commandStrAppendable, standardOutput, errorOutput);

      • MSDOS

        🡅  🡇  ⇈  ⮫ 🗕  🗗  🗖 
        public MSDOS​(java.lang.Appendable standardOutput,
             java.lang.Appendable errorOutput)
        This constructor assigns values to these internal Appendable fields: standardOutput and errorOutput

        Assigning null: Any of this class Appendable's may be assigned null. When an Appendable is assigned null, it is simply ignored. NullPointerException will not throw, and any output text that would be appended, isn't appended.
        Parameters:
        standardOutput - This Appendable is assigned to the internal OSCommands field: standardOutput. This Appendabe, as the name hopefully implies, allows a user to collect any / all text sent by the process to Standard-Output.

        Please review the documentation for that field to better understand it's use. Also, keep in mind that null may be passed to this parameter, and if / when it is the corresponding Appendable field will simply be ignored during the process execution.
        errorOutput - This Appendable is assigned to the internal OSCommands field: errorOutput. This Appendabe, as the name hopefully implies, allows a user to collect any / all text sent by the process to Error-Output.

        Please review the documentation for that field to better understand it's use. Also, keep in mind that null may be passed to this parameter, and if / when it is the corresponding Appendable field will simply be ignored during the process execution.
        See Also:
        OSCommands.standardOutput, OSCommands.errorOutput
        Code:
        Exact Constructor Body:
         super(standardOutput, errorOutput);

      • MSDOS

        🡅  🡇  ⇈  ⮫ 🗕  🗗  🗖 
        protected MSDOS​(MSDOS other)
        Used by the method clone().
        Parameters:
        other - Another instance of this class.
        Code:
        Exact Constructor Body:
         super(other);

    • Method Detail

      • clone

        🡅  🡇  ⇈  ⮫ 🗕  🗗  🗖 
        public MSDOS clone()
        Creates a clone of 'this' instance. Though unlikely of much use, this could conceivably have some function if similar, but non-identical, output mechanisms were being used.
        Specified by:
        clone in class OSCommands
        Returns:
        An exact copy of 'this' instance - one in which all output Appendable's have had their references copied into the new instance.
        Code:
        Exact Method Body:
         return new MSDOS(this);

      • COPY

        🡅  🡇  ⇈  ⮫ 🗕  🗗  🗖 
        public OSResponse COPY​(java.lang.String src,
                       java.lang.String target)
                throws java.io.IOException
        MS-DOS Command: COPY

        UNIX or DOS Shell Command:
        C:\>COPY <src> <target>
        Parameters:
        src - MS-DOS 'COPY' command's "source" argument
        target - The 'COPY' command's "target" argument
        Returns:
        Returns an instance of OSResponse. This response-Object (data-record) class holds four public, final fields:
        ① Process response-code
        ② Text sent to Standard-Output (as a java.lang.String)
        ③ Text sent to Error-Output (also as a String)
        ④ The original Command-String

        This OSResponse instance may be discarded without any effect on Process Execution. It is only provided as a convenience in case more information is required about the results of the O/S command invocation.

        Process Status: Upon completion of this method, the Operating-System java.lang.Process is guaranteed to have run to completion (or to have failed and been interrupted). If the process was interrupted, the response-code will indicate this using the value INTERRUPTED
        Throws:
        java.io.IOException - If there are problems while invoking the operating-system command
        See Also:
        OSCommands.printAndRun(String[])
        Code:
        Exact Method Body:
         String[] command = { "COPY", src, target };

 return printAndRun(command);

      • COPY

        🡅  🡇  ⇈  ⮫ 🗕  🗗  🗖 
        public OSResponse COPY​(java.util.Vector<java.lang.String> src,
                       java.lang.String target)
                throws java.io.IOException
        MS-DOS Command: COPY

        UNIX or DOS Shell Command:
        C:\>COPY <src.elementAt(0)> <src.elementAt(1)> ... <src.elementAt(src.size()-1)> <target>
        Parameters:
        src - This may be a list of files to be copied to a target directory
        target - This is the target directory for the files listed.
        Returns:
        Returns an instance of OSResponse. This response-Object (data-record) class holds four public, final fields:
        ① Process response-code
        ② Text sent to Standard-Output (as a java.lang.String)
        ③ Text sent to Error-Output (also as a String)
        ④ The original Command-String

        This OSResponse instance may be discarded without any effect on Process Execution. It is only provided as a convenience in case more information is required about the results of the O/S command invocation.

        Process Status: Upon completion of this method, the Operating-System java.lang.Process is guaranteed to have run to completion (or to have failed and been interrupted). If the process was interrupted, the response-code will indicate this using the value INTERRUPTED
        Throws:
        java.io.IOException - If there are problems while invoking the operating-system command
        See Also:
        OSCommands.printAndRun(String[])
        Code:
        Exact Method Body:
         String[] command = new String[src.size() + 2];
 command[0] = "COPY";
 command[src.size() + 1] = target;

 for (int i=0; i < src.size(); i++) command[1 + i] = src.elementAt(i);

 return printAndRun(command);

      • COPY

        🡅  🡇  ⇈  ⮫ 🗕  🗗  🗖 
        public OSResponse COPY​(java.lang.String[] src,
                       java.lang.String target)
                throws java.io.IOException
        MS-DOS Command: COPY

        UNIX or DOS Shell Command:
        C:\>COPY <src[0]> <src[1]> ... <src[src.length-1]> <target>
        Parameters:
        src - This may be a list of files to be copied to a target directory
        target - This is the target directory for the files listed.
        Returns:
        Returns an instance of OSResponse. This response-Object (data-record) class holds four public, final fields:
        ① Process response-code
        ② Text sent to Standard-Output (as a java.lang.String)
        ③ Text sent to Error-Output (also as a String)
        ④ The original Command-String

        This OSResponse instance may be discarded without any effect on Process Execution. It is only provided as a convenience in case more information is required about the results of the O/S command invocation.

        Process Status: Upon completion of this method, the Operating-System java.lang.Process is guaranteed to have run to completion (or to have failed and been interrupted). If the process was interrupted, the response-code will indicate this using the value INTERRUPTED
        Throws:
        java.io.IOException - If there are problems while invoking the operating-system command
        See Also:
        OSCommands.printAndRun(String[])
        Code:
        Exact Method Body:
         String[] command = new String[src.length + 2];
 command[0] = "COPY";
 command[src.length + 1] = target;

 for (int i=0; i < src.length; i++) command[1 + i] = src[i];

 return printAndRun(command);

      • DEL

        🡅  🡇  ⇈  ⮫ 🗕  🗗  🗖 
        public OSResponse DEL​(java.lang.String s1)
               throws java.io.IOException
        MS-DOS Command: DEL

        UNIX or DOS Shell Command:
        C:\>DEL <s1>
        Parameters:
        s1 - The item to be removed, using an MS-DOS command.
        Returns:
        Returns an instance of OSResponse. This response-Object (data-record) class holds four public, final fields:
        ① Process response-code
        ② Text sent to Standard-Output (as a java.lang.String)
        ③ Text sent to Error-Output (also as a String)
        ④ The original Command-String

        This OSResponse instance may be discarded without any effect on Process Execution. It is only provided as a convenience in case more information is required about the results of the O/S command invocation.

        Process Status: Upon completion of this method, the Operating-System java.lang.Process is guaranteed to have run to completion (or to have failed and been interrupted). If the process was interrupted, the response-code will indicate this using the value INTERRUPTED
        Throws:
        java.io.IOException - If there are problems while invoking the operating-system command
        See Also:
        OSCommands.printAndRun(String[])
        Code:
        Exact Method Body:
         String[] command = { "DEL", s1 };

 return printAndRun(command);

      • DEL

        🡅  ⇈  ⮫ 🗕  🗗  🗖 
        public OSResponse DEL​(java.lang.String[] sArr)
               throws java.io.IOException
        MS-DOS Command: DEL

        UNIX or DOS Shell Command:
        C:\>DEL <sArr[0]> <sArr[1]> ... <sArr[sArr.length-1]>
        Parameters:
        sArr - An String[] array which is added to the end of this MS-DOS command. These will be the item(s) removed by the 'DEL' command.
        Returns:
        Returns an instance of OSResponse. This response-Object (data-record) class holds four public, final fields:
        ① Process response-code
        ② Text sent to Standard-Output (as a java.lang.String)
        ③ Text sent to Error-Output (also as a String)
        ④ The original Command-String

        This OSResponse instance may be discarded without any effect on Process Execution. It is only provided as a convenience in case more information is required about the results of the O/S command invocation.

        Process Status: Upon completion of this method, the Operating-System java.lang.Process is guaranteed to have run to completion (or to have failed and been interrupted). If the process was interrupted, the response-code will indicate this using the value INTERRUPTED
        Throws:
        java.io.IOException - If there are problems while invoking the operating-system command
        See Also:
        OSCommands.printAndRun(String[])
        Code:
        Exact Method Body:
         String[] command = new String[sArr.length + 1];
 command[0] = "DEL";

 for (int i=0; i < sArr.length; i++) command[i + 1] = sArr[i];

 return printAndRun(command);