import net.lingala.zip4j.ZipFile;
import net.lingala.zip4j.exception.ZipException;
import net.lingala.zip4j.model.ZipParameters;
import net.lingala.zip4j.model.enums.EncryptionMethod;
import net.lingala.zip4j.model.enums.AesKeyStrength;
import java.io.File;
import java.io.IOException;

public class SampleClass{

public static void main(String[] args)
throws ZipException,
IOException{
ZipFile zip = null;

try{
ZipParameters zp = new ZipParameters();
zp.setEncryptFiles(true);
zp.setEncryptionMethod
(EncryptionMethod.AES);
zp.setAesKeyStrength
(AesKeyStrength.KEY_STRENGTH_256);

zip = new ZipFile("myzip.zip","password".toCharArray());
zip.addFolder(new File("folder"), zp);
zip.addFile(new File("img.jpg"));
}
finally{
if(zip != null)
zip.close();
}

System.out.println
("main thread end");
}
}