(Java) Zip Append Files and Entry Type

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Demonstrates appending files to a zip object for writing a .zip. Also explains the "entry type".

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import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    boolean success;

    CkZip zip = new CkZip();
    CkZipEntry entry;

    String zipPath = "c:/temp/qa_output/out.zip";

    // Initialize the zip object with the path of the .zip to be created.
    zip.NewZip(zipPath);

    // Recursively append to the zip object the paths of the files and directories in a directory tree.
    // At this point we are not creating the .zip, nor are we reading the contents of the files.
    // We are simply appending references to the files and directories in the local filesystem
    // that will get processed when WriteZip is called.
    boolean recurse = true;
    boolean saveExtraPath = false;
    boolean archiveOnly = false;
    boolean includeHidden = true;
    boolean includeSystem = false;
    success = zip.AppendFilesEx("c:/temp/files_to_zip",recurse,saveExtraPath,archiveOnly,includeHidden,includeSystem);
    if (success == false) {
        System.out.println(zip.lastErrorText());
        return;
        }

    // Note: We can iterate over the references to the files that will be processed when zipping:
    int count = zip.get_NumEntries();
    int i = 0;
    while (i < count) {
        entry = zip.GetEntryByIndex(i);
        System.out.println(entry.fileName() + " entryType = " + entry.get_EntryType());

        i = i+1;
        }

    System.out.println("----");

    // Sample output for the above loop:
    // The entry type = 1, because these are entries that are references to files in the local filesystem
    // that are to be processed when the zip is written.

    // hamlet.xml entryType = 1
    // hello.pdf entryType = 1
    // ...
    // ...

    // Possible entry type values:
    // 0 - Mapped Entry: An entry in an existing Zip file.
    // 1 - File Entry: A file not yet in memory, but referenced. These entries are added by calling AppendFiles, AppendFilesEx, AppendOneFileOrDir, etc.
    // 2 - Data Entry: An entry containing uncompressed data from memory. These entries are added by calling AppendData, AppendString, etc.
    // 3 - Null Entry: An entry that no longer exists in the .zip.
    // 4 - New Directory Entry: A directory entry added by calling AppendNewDir. 

    // The application can continue to add additional entries.
    // For example:
    CkZipEntry eTemp = zip.AppendString("helloWorld.txt","Hello World");

    // Now let's have a look at what will get zipped when we write the zip:
    count = zip.get_NumEntries();
    i = 0;
    while (i < count) {
        entry = zip.GetEntryByIndex(i);
        System.out.println(entry.fileName() + " entryType = " + entry.get_EntryType());

        i = i+1;
        }

    System.out.println("----");

    // You can see that "helloWorld.txt" is added. 
    // Its entryType = 2, which means it is in-memory data (it is not a reference to a file in the local filesystem).

    // hamlet.xml entryType = 1
    // hello.pdf entryType = 1
    // ...
    // ...
    // helloWorld.txt entryType = 2

    // ----------------------------------------------------------------------------
    // Now we'll write the zip to a .zip file.
    zip.put_FileName(zipPath);
    success = zip.WriteZip();
    if (success == false) {
        System.out.println(zip.lastErrorText());
        return;
        }

    // Let's look again at the entries in the .zip
    count = zip.get_NumEntries();
    i = 0;
    while (i < count) {
        entry = zip.GetEntryByIndex(i);
        System.out.println(entry.fileName() + " entryType = " + entry.get_EntryType());

        i = i+1;
        }

    System.out.println("----");

    // After writing the .zip, the entry types change to 0.
    // Entry type 0 indicates that it's a "mapped entry", which is an entry in an existing (and currently open) .zip file.

    // hamlet.xml entryType = 0
    // hello.pdf entryType = 0
    // ...
    // ...
    // helloWorld.txt entryType = 0

    // ----------------------------------------------------------------------------
    // If desired, we could continue adding additional entries of any kind (files or data) to the currently open .zip archive...

    eTemp = zip.AppendString("helloWorld2.txt","Hello World 2");

    // Write the .zip, including the new entries..
    success = zip.WriteZip();
    if (success == false) {
        System.out.println(zip.lastErrorText());
        return;
        }

    // Finally, let's look again at the entries in the .zip
    count = zip.get_NumEntries();
    i = 0;
    while (i < count) {
        entry = zip.GetEntryByIndex(i);
        System.out.println(entry.fileName() + " entryType = " + entry.get_EntryType());

        i = i+1;
        }

    System.out.println("----");

    // hamlet.xml entryType = 0
    // hello.pdf entryType = 0
    // ...
    // ...
    // helloWorld.txt entryType = 0
    // helloWorld2.txt entryType = 0

    zip.CloseZip();

    System.out.println("Success");
  }
}