import java.io.File;
import net.lingala.zip4j.core.ZipFile;
import net.lingala.zip4j.exception.ZipException;
import net.lingala.zip4j.model.ZipParameters;

public class ZipUtil {
  private ZipFile zf;
  private ZipParameters prms;
  public void zipWithPassword(String srcFile, String zipFile, String strPass) throws ZipException {
     try{
     zf = new ZipFile(zipFile);
     prms = new ZipParameters();
     prms.setPassword(strPass);
     prms.setAesKeyStrength(net.lingala.zip4j.util.Zip4jConstants.AES_STRENGTH_256 );
     prms.setCompressionMethod(net.lingala.zip4j.util.Zip4jConstants.COMP_DEFLATE );
     prms.setCompressionLevel(net.lingala.zip4j.util.Zip4jConstants.DEFLATE_LEVEL_MAXIMUM);
     prms.setEncryptionMethod(net.lingala.zip4j.util.Zip4jConstants.ENC_METHOD_STANDARD);
     File fileSrc = new File(srcFile);
     zf.createZipFile(fileSrc, prms);
     } catch (ZipException zex){
       zex.printStackTrace();
     }
  }
}

prms.setEncryptFiles(true);