Create Zip File With CRC32 Checksum Example

/*
	Create Zip File With CRC32 Checksum Example
	This Java example shows how to create a zip file and generate the 
	checksum value using Java CheckedOutputStream and CRC32 classes.
*/
 
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.zip.CRC32;
import java.util.zip.CheckedOutputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;
 
public class CompressFileWithCRC32Checksum {
 
	public static void main(String args[])
	{		
		String zipFile = "C:/FileIO/zipdemo.zip";
		String sourceFile = "C:/FileIO/sourcefile.doc";
 
		//		create byte buffer
		byte[] buffer = new byte[1024]; 
 
		try
		{
			//create object of FileOutputStream
			FileOutputStream fout = new FileOutputStream(zipFile);
 
			/*
			 * Create an object of CheckedOutputStream using,
			 * 
			 * CheckedOutputStream(OutputStream out, Checksum checksum)
			 * 
			 * constructor.
			 * 
			 * The second argument is the Checksum algorithm we want to use.
			 * It can be either CRC32 or Adler32.
			 *  
			 */
 
			 CheckedOutputStream checksum = new CheckedOutputStream(fout, new CRC32());
 
			 //create an object of ZipOutputStream
			ZipOutputStream zout = new ZipOutputStream(checksum);
 
			//create object of FileInputStream for source file
			FileInputStream fin = new FileInputStream(sourceFile);
 
			zout.putNextEntry(new ZipEntry(sourceFile));
 
			int length;
 
			while((length = fin.read(buffer)) > 0)
			{
			   zout.write(buffer, 0, length);
			}
 
			zout.closeEntry();
 
			//close the InputStream
			fin.close();
 
			//close the ZipOutputStream
			zout.close();
 
			System.out.println("Zip file has been created!");
 
			/*
			 * Get the generated checksum value using
			 * 
			 * Checksum getChecksum()
			 * 
			 * method.
			 * 
			 * This method returns the checksum for the output stream. 
			 */
			System.out.println("CRC32 Checksum is : " + checksum.getChecksum().getValue());
		}
		catch(IOException ioe)
		{
			System.out.println("IOException : " + ioe);
		}
 
 
	}
 
}
 
/*
Output of this example would be
Zip file has been created!
CRC32 Checksum is : 1481449702
*/