Java

Iterate Over ZIP Entries Using EntryAt

This example demonstrates how to use the EntryAt method to iterate over all entries contained within a ZIP archive.

The EntryAt method retrieves a ZipEntry object for a given zero-based index.

This is useful for:

• Enumerating all entries in a ZIP archive
• Inspecting filenames, sizes, and timestamps
• Searching or filtering ZIP contents

Suppose the ZIP archive contains:

docs/readme.txt
images/logo.png
data/config.json

The example loops through all ZIP entries and prints information about each entry.

Java

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[])
  {
    boolean success = false;

    //  Open an existing ZIP archive.
    CkZip zip = new CkZip();

    success = zip.OpenZip("example.zip");
    if (success == false) {
        System.out.println(zip.lastErrorText());
        return;
        }

    //  Get the total number of entries in the ZIP archive.
    int numEntries = zip.get_NumEntries();

    System.out.println("Number of ZIP entries = " + numEntries);

    //  Create a ZipEntry object that will be reused
    //  for each entry retrieved by EntryAt.
    CkZipEntry entry = new CkZipEntry();

    //  Iterate over all ZIP entries.
    int i = 0;
    while (i < numEntries) {

        //  Retrieve the entry at index i.
        success = zip.EntryAt(i,entry);
        if (success == false) {
            System.out.println(zip.lastErrorText());
            return;
            }

        System.out.println("Entry " + i);
        System.out.println("  FileName: " + entry.fileName());
        System.out.println("  Uncompressed Length: " + entry.get_UncompressedLength());
        System.out.println("  Compressed Length: " + entry.get_CompressedLength());
        System.out.println("");

        i = i+1;
        }

    //  Sample output:
    //  
    //  Entry 0
    //    FileName: docs/readme.txt
    //    Uncompressed Length: 1204
    //    Compressed Length: 512
    //  
    //  Entry 1
    //    FileName: images/logo.png
    //    Uncompressed Length: 84211
    //    Compressed Length: 84102
    //  

    zip.CloseZip();

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