(Java) Decompress Large Text File in Blocks

Decompresses a large text file in blocks, and compares the restored (decompressed) file with the original to make sure it's correct.

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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.

    // First, let's compress a text file.
    // We'll then decompress in blocks, and compare the decompressed with the original file.

    // Compress a text file:
    CkCompression compress = new CkCompression();
    compress.put_Algorithm("deflate");

    boolean success = compress.CompressFile("qa_data/hamlet.xml","qa_data/hamlet_compressed.dat");
    if (success != true) {
        System.out.println(compress.lastErrorText());
        return;
        }

    CkFileAccess fac = new CkFileAccess();

    // Examine the uncompressed and compressed sizes:
    String originalPath = "qa_data/hamlet.xml";
    // Note: The FileSize method returns a signed 32-bit integer.  If the file is potentially larger than 2GB, call FileSizeStr instead to return
    // the size of the file as a string, then convert to an integer value.
    System.out.println("uncompressed size: " + fac.FileSize(originalPath));
    System.out.println("compressed size: " + fac.FileSize("qa_data/hamlet_compressed.dat"));

    // Decompress in blocks..
    CkFileAccess facSrc = new CkFileAccess();
    CkFileAccess facDest = new CkFileAccess();

    facSrc.OpenForRead("qa_data/hamlet_compressed.dat");

    // If we compress in 32K chunks, find out how many blocks there will be.
    int blockSize = 32768;
    int numBlocks = facSrc.GetNumBlocks(blockSize);

    // Open an output file for the decompressed data.
    String restoredPath = "qa_output/hamlet_restored.xml";
    success = facDest.OpenForWrite(restoredPath);
    if (success != true) {
        System.out.println(facDest.lastErrorText());
        return;
        }

    String decompressedStr;
    CkByteData compressedBytes = new CkByteData();

    int i = 0;
    while (i < numBlocks) {
        success = facSrc.ReadBlock(i,blockSize,compressedBytes);
        if (i == 0) {
            decompressedStr = compress.beginDecompressString(compressedBytes);
            }
        else {
            decompressedStr = compress.moreDecompressString(compressedBytes);
            }

        facDest.AppendText(decompressedStr,"utf-8");

        i = i+1;
        }

    // At the very end, flush any remaining content, if any.
    decompressedStr = compress.endDecompressString();
    facDest.AppendText(decompressedStr,"utf-8");

    facSrc.FileClose();
    facDest.FileClose();

    // Examine the size of the restored file.
    System.out.println("restored size: " + fac.FileSize(restoredPath));

    // Compare the contents of the original with the restored.
    boolean bEqualContents = fac.FileContentsEqual(restoredPath,originalPath);
    System.out.println("Contents Equal: " + bEqualContents);
  }
}