int available()

优质
小牛编辑
138浏览
2023-12-01

描述 (Description)

到达EOF后, java.util.zip.InflaterInputStream.available()方法返回0,否则始终返回1。

声明 (Declaration)

以下是java.util.zip.InflaterInputStream.available()方法的声明。

public int available()
   throws IOException

返回值 (Returns)

在达到基础输入流结束后为零,否则始终返回1。

异常 (Exceptions)

  • IOException - 如果发生I/O错误或此流已关闭。

例子 (Example)

以下示例显示了java.util.zip.InflaterInputStream.available()方法的用法。

package cn.xnip;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.zip.DataFormatException;
import java.util.zip.Deflater;
import java.util.zip.InflaterInputStream;
public class InflaterInputStreamDemo {
   public static void main(String[] args) throws DataFormatException, IOException {
      String message = "Welcome to xnip.cn;"
         +"Welcome to xnip.cn;"
         +"Welcome to xnip.cn;"
         +"Welcome to xnip.cn;"
         +"Welcome to xnip.cn;"
         +"Welcome to xnip.cn;"
         +"Welcome to xnip.cn;"
         +"Welcome to xnip.cn;"
         +"Welcome to xnip.cn;"
         +"Welcome to xnip.cn;";
      System.out.println("Original Message length : " + message.length());
      byte[] input = message.getBytes("UTF-8");
      int length = message.length();
      // Compress the bytes
      byte[] output = new byte[1024];
      Deflater deflater = new Deflater();
      deflater.setInput(input);
      deflater.finish();
      int compressedDataLength = deflater.deflate(output,0 , output.length, Deflater.NO_FLUSH);
      System.out.println("Total uncompressed bytes input :" + deflater.getTotalIn());
      System.out.println("Compressed Message Checksum :" + deflater.getAdler());     
      deflater.finished();
      System.out.println("Compressed Message length : " + compressedDataLength);
      ByteArrayInputStream bin = new ByteArrayInputStream(output);
      InflaterInputStream inflaterInputStream = new InflaterInputStream(bin);
      byte[] result = new byte[1024];
      ByteArrayOutputStream buffer = new ByteArrayOutputStream();
      while(inflaterInputStream.available() != 0){
         buffer.write(inflaterInputStream.read());
      }
      inflaterInputStream.close();
      // Decode the bytes into a String
      String message1 = new String(buffer.toByteArray(),0, length,"UTF-8");
      System.out.println(message.equals(message1));
   }
}

让我们编译并运行上面的程序,这将产生以下结果 -

Original Message length : 300
Total uncompressed bytes input :300
Compressed Message Checksum :368538129
Compressed Message length : 42
true