(Java) Compress and Decompress Base64

Imagine we have data represented as a base64 string. This example demonstrates how to decode, compress, and re-encode to smaller base64 representing the compressed data.

Note: This example requires Chilkat v9.5.0.66 or greater.

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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 assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    boolean success;

    String strBase64 = "VGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZWQgb3ZlciB0aGUgbGF6eSBkb2cuDQpUaGUgcXVpY2sgYnJvd24gZm94IGp1bXBlZCBvdmVyIHRoZSBsYXp5IGRvZy4NClRoZSBxdWljayBicm93biBmb3gganVtcGVkIG92ZXIgdGhlIGxhenkgZG9nLg0KVGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZWQgb3ZlciB0aGUgbGF6eSBkb2cuDQpUaGUgcXVpY2sgYnJvd24gZm94IGp1bXBlZCBvdmVyIHRoZSBsYXp5IGRvZy4NCg0K";

    CkCompression compress = new CkCompression();
    compress.put_Algorithm("deflate");

    CkBinData binDat = new CkBinData();
    // Load the base64 data into a BinData object.
    // This decodes the base64. The decoded bytes will be contained in the BinData.
    binDat.AppendEncoded(strBase64,"base64");

    // Compress the BinData.
    compress.CompressBd(binDat);

    // Get the compressed data in base64 format:
    String compressedBase64 = binDat.getEncoded("base64");
    System.out.println("compressed base64:");
    System.out.println(compressedBase64);

    // The compressed base64 is: C8lIVSgszUzOVkgqyi/PU0jLr1DIKs0tSE1RyC9LLVIoAcrnJFZVKqTkp+vxcoUMYeW8XAA=

    // Now decompress:
    binDat.Clear();
    binDat.AppendEncoded(compressedBase64,"base64");
    compress.DecompressBd(binDat);

    String decompressedBase64 = binDat.getEncoded("base64");
    System.out.println("decompressed base64:");
    System.out.println(decompressedBase64);

    // The output is the original data:
    // VGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZWQgb3ZlciB0aGUgbGF6eSBkb2cuDQpUaGUgcXVpY2sgYnJvd24gZm94IGp1bXBlZCBvdmVyIHRoZSBsYXp5IGRvZy4NClRoZSBxdWljayBicm93biBmb3gganVtcGVkIG92ZXIgdGhlIGxhenkgZG9nLg0KVGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZWQgb3ZlciB0aGUgbGF6eSBkb2cuDQpUaGUgcXVpY2sgYnJvd24gZm94IGp1bXBlZCBvdmVyIHRoZSBsYXp5IGRvZy4NCg0K
  }
}