Exemplo do método java.util.zip.DeflaterOutputStream.finish ()

Descrição

o java.util.zip.DeflaterOutputStream.finish()método termina de gravar dados compactados no fluxo de saída sem fechar o fluxo subjacente. Use este método ao aplicar vários filtros em sucessão ao mesmo fluxo de saída.

Declaração

A seguir está a declaração para java.util.zip.DeflaterOutputStream.finish() método.

public void finish()
   throws IOException

Exceções

  • IOException - se ocorreu um erro de E / S.

Exemplo

O exemplo a seguir mostra o uso do método java.util.zip.DeflaterOutputStream.finish ().

package com.tutorialspoint;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.Arrays;
import java.util.zip.Adler32;
import java.util.zip.CheckedInputStream;
import java.util.zip.DataFormatException;
import java.util.zip.Deflater;
import java.util.zip.DeflaterInputStream;
import java.util.zip.DeflaterOutputStream;
import java.util.zip.Inflater;
import java.util.zip.InflaterInputStream;

public class DeflaterOutputStreamDemo {

   public static void main(String[] args) throws DataFormatException, IOException {
      String message = "Welcome to TutorialsPoint.com;"
         +"Welcome to TutorialsPoint.com;"
         +"Welcome to TutorialsPoint.com;"
         +"Welcome to TutorialsPoint.com;"
         +"Welcome to TutorialsPoint.com;"
         +"Welcome to TutorialsPoint.com;"
         +"Welcome to TutorialsPoint.com;"
         +"Welcome to TutorialsPoint.com;"
         +"Welcome to TutorialsPoint.com;"
         +"Welcome to TutorialsPoint.com;";
      String dictionary = "Welcome";
      System.out.println("Original Message length : " + message.length());
      byte[] input = message.getBytes("UTF-8");

      // Compress the bytes
      ByteArrayOutputStream arrayOutputStream = new ByteArrayOutputStream();
      DeflaterOutputStream outputStream = new DeflaterOutputStream(arrayOutputStream);
      outputStream.write(input);
      outputStream.finish();
      outputStream.close();

      //Read and decompress the data
      byte[] readBuffer = new byte[5000];
      ByteArrayInputStream arrayInputStream = 
         new ByteArrayInputStream(arrayOutputStream.toByteArray());
      InflaterInputStream inputStream = new InflaterInputStream(arrayInputStream);
      int read = inputStream.read(readBuffer);

      //Should hold the original (reconstructed) data
      byte[] result = Arrays.copyOf(readBuffer, read);

      // Decode the bytes into a String
      message = new String(result, "UTF-8");
    
      System.out.println("UnCompressed Message length : " + message.length());
   }
}

Vamos compilar e executar o programa acima, isso produzirá o seguinte resultado -

Original Message length : 300
UnCompressed Message length : 300