boolean markSupported()

描述 (Description)

java.util.zip.InflaterInputStream.markSupported()方法测试此输入流是否支持mark和reset方法。 InflaterInputStream的markSupported方法返回false。

声明 (Declaration)

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

public boolean markSupported()

返回值 (Returns)

一个布尔值，指示此流类型是否支持mark和reset方法。

例子 (Example)

以下示例显示了java.util.zip.InflaterInputStream.markSupported（）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();
      if(inflaterInputStream.markSupported()){
         inflaterInputStream.mark(0);  
      }
      if(inflaterInputStream.markSupported()){
         inflaterInputStream.reset();  
      }
      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