Java 使用 GZIP 进行压缩和解压缩详解编程语言

  
import java.util.zip.GZIPOutputStream; 
import java.io.FileOutputStream; 
import java.io.FileInputStream; 
import java.io.FileNotFoundException; 
import java.io.IOException; 
 
/** 
 * ----------------------------------------------------------------------------- 
 * Used to provide an example of compressing a file using the GZIP Format. 
 * 
 * @version 1.0 
 * @author  Jeffrey M. Hunter  ([email protected]) 
 * @author  <a href="http://www.idevelopment.info">http://www.idevelopment.info 
 * ----------------------------------------------------------------------------- 
 */ 
 
public class CompressFileGZIP { 
 
    /** 
     * Perform file compression. 
     * @param inFileName Name of the file to be compressed 
     */ 
    private static void doCompressFile(String inFileName) { 
 
        try { 
         
            System.out.println("Creating the GZIP output stream."); 
            String outFileName = inFileName + ".gz"; 
            GZIPOutputStream out = null; 
            try { 
                out = new GZIPOutputStream(new FileOutputStream(outFileName)); 
            } catch(FileNotFoundException e) { 
                System.err.println("Could not create file: " + outFileName); 
                System.exit(1); 
            } 
                     
 
            System.out.println("Opening the input file."); 
            FileInputStream in = null; 
            try { 
                in = new FileInputStream(inFileName); 
            } catch (FileNotFoundException e) { 
                System.err.println("File not found. " + inFileName); 
                System.exit(1); 
            } 
 
            System.out.println("Transfering bytes from input file to GZIP Format."); 
            byte[] buf = new byte[1024]; 
            int len; 
            while((len = in.read(buf)) > 0) { 
                out.write(buf, 0, len); 
            } 
            in.close(); 
 
            System.out.println("Completing the GZIP file"); 
            out.finish(); 
            out.close(); 
         
        } catch (IOException e) { 
            e.printStackTrace(); 
            System.exit(1); 
        } 
 
    } 
 
    /** 
     * Sole entry point to the class and application. 
     * @param args Array of String arguments. 
     */ 
    public static void main(String[] args) { 
     
        if (args.length != 1) { 
            System.err.println("Usage: java CompressFileGZIP filename"); 
        } else { 
            doCompressFile(args[0]); 
        } 
 
             
    } 
 
}