import java.util.zip.*;
import java.io.*;

//  File:  jkzip.java
//
/**
 *
 *  This class will allow you to perform basic pkzip compatible
 *  data compression. <p>
 *
 *  The basic steps are: <br>
 *    1.  Create the zip output stream  <br>
 *    2.  Open source data file  <br>
 *    3.  Create the zip entry  <br>
 *    4.  Put the entry  <br>
 *    5.  Read source and write the data to the zip output stream  <br>
 *    6.  Close the zip entry and other open streams  <br>
 *
 *  <p>
 *  Command syntax <br>
 *  <pre> Usage: java jkzip zipfile [files] </pre> <br>
 *
 *  <p>
 *  NOTE:  This version does not recurse sub-directories.
 *
 *  @author Chad (shod) Darby,  darby@j-nine.com
 *  @version 1.13, 27 Sep 97
 *
 *
 */
public class jkzip
{

  //-------------------------------------------------
  // DATA MEMBERS
  //
  String archiveFileName;
  String fileNamesArray[];

  //-------------------------------------------------
  //  CONSTRUCTORS
  //
  /**
   *
   *  The constructor is used to create a new jkzip object based
   *  on the command line arguments. <br>
   *  Usage: <pre>  java jkzip zipfile [files] </pre> </b> <br>
   *
   *  @param args - a string array of command line arguments.
   *
   */
  public jkzip(String args[])
  {
    if (args.length == 0)
    {
      System.out.println(getUsageString());
      System.exit(1);
    }

    archiveFileName = args[0];

    // create the fileNames array
    //
    // if user supplied list of file(s) then args.length
    // will be greater than 1.
    //
    if (args.length > 1)
    {
      fileNamesArray = new String[args.length - 1];

      for (int j=0; j < fileNamesArray.length; j++)
      {
        fileNamesArray[j] = args[j+1];
      }
    }

    // if user didn't supply files then zip the entire directory
    //
    else if (args.length == 1)
    {
      File currentDirectory = new File(".");
      fileNamesArray = currentDirectory.list();
    }

  }

  //-------------------------------------------------
  //  METHODS
  //
  /**
   *  Reads the data source and writes the compressed file. <br>
   *
   *  <p>
   *  The basic steps are: <br>
   *    1.  Create the zip output stream  <br>
   *    2.  Open source data file  <br>
   *    3.  Create the zip entry  <br>
   *    4.  Put the entry  <br>
   *    5.  Read source and write the data to the zip output stream  <br>
   *    6.  Close the zip entry and other open streams  <br>
   */
  public void zipIt()
  {

    BufferedInputStream sourceStream;
    File theFile;
    FileInputStream fis;

    ZipOutputStream targetStream;
    FileOutputStream fos;
    ZipEntry theEntry;

    final int DATA_BLOCK_SIZE = 2048;
    int byteCount;
    byte data[];

    try
    {

      // 1.  create the ZipOutputStream
      //
      System.out.println("Creating ZIP: " + archiveFileName);
      fos = new FileOutputStream(archiveFileName);
      targetStream = new ZipOutputStream(fos);
      targetStream.setMethod(ZipOutputStream.DEFLATED);

      // loop thru the array
      for (int i=0; i < fileNamesArray.length; i++)
      {

        theFile = new File(fileNamesArray[i]);

        //  check if file is a directory, if so then skip
        if (theFile.isDirectory())
        {
          // i won't recurse directories so let's skip
          System.out.println("\tSkipping directory: " + theFile);
          continue;
        }

        // 2.  open source file
        //
        fis = new FileInputStream(fileNamesArray[i]);
        sourceStream = new BufferedInputStream(fis);

        // 3.  create the ZipEntry
        //
        theEntry = new ZipEntry(fileNamesArray[i]);
        System.out.print("\tAdding: " + theEntry.getName());

        // 4.  put the entry
        //
        targetStream.putNextEntry(theEntry);

        // 5.  read source data and write target data
        //     to compressed output stream
        //
        data = new byte[DATA_BLOCK_SIZE];

        while ( (byteCount = sourceStream.read(data, 0, DATA_BLOCK_SIZE)) != -1)
        {
          targetStream.write(data, 0, byteCount);
        }

        targetStream.flush();

        // 6.  close the entry
        //
        System.out.println(", done.");
        targetStream.closeEntry();

        sourceStream.close();

      } // end for loop

      targetStream.close();

    }

    catch (IOException e)
    {
      e.printStackTrace();
    }

  }

  /**
   *
   *  Returns the usage string for this class.
   *
   *  @return Returns the usage string.
   *
   */
  public String getUsageString()
  {
    String temp = null;

    temp  =  "\nJKZIP ver 1.13\n\n";
    temp +=  "Usage: java jkzip zipfile [files]\n";

    return temp;
  }

  public static void main(String args[])
  {
    jkzip myApp = new jkzip(args);

    myApp.zipIt();
  }

}