java gzipoutputstream压缩比例大概是多少

Posted 2023-03-23

参考技术A It is my decision,It is my life.
JAVA对字符串的压缩与解压缩

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import java.util.zip.ZipOutputStream;

public class ZipUtils

/**

* 使用gzip进行压缩
*/
public static String gzip(String primStr)
if (primStr == null || primStr.length() == 0)
return primStr;
本回答被提问者采纳

java程序压缩和解压zip文件

需要了解的知识汇总：
DeflaterOutputStream ：压缩类的基类。
ZipOutputStream ：DeflaterOutputStream的一个子类，把数据压缩成Zip文件格式
GZIPOutputStream ：DeflaterOutputStream的一个子类，把数据压缩成GZip文件格式

InflaterInputStream ：解压缩类的基类
ZipInputStream ：InflaterInputStream的一个子类，能解压缩Zip格式的数据
GZIPInputStream ：InflaterInputStream的一个子类，能解压缩Zip格式的数据

ZipEntry 类：表示 ZIP 文件条目
ZipFile 类：此类用于从 ZIP 文件读取条目

以zipentry来命名zip内文件列表。
以FileInputStream来读取文件。
以zipoutputstream输出流进行压缩文件写入。
逻辑简单好懂，附件带有实例，解压即可运行。
百度网盘实例链接：https://pan.baidu.com/s/1VSs-UqtU_3Lld2H7-1dMMg
提取码：mcb3

package com.crscd.server.web.cbtc2.filezip;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStreamReader;

public class FileZip {
/*

• author:zhao_anan 20190424 zip compress program
  /
  /public void zip(ZipOutputStream out, File f, String base, boolean first)
  throws Exception {
  if (first) {
  if (f.isDirectory()) {
  out.putNextEntry(new ZipEntry("/"));
  base = base + f.getName();
  first = false;
  } else
  base = f.getName();
  }
  if (f.isDirectory()) {
  File[] fl = f.listFiles();
  base = base + "/";
  for (int i = 0; i < fl.length; i++) {
  zip(out, fl[i], base + fl[i].getName(), first);
  }
  } else {
  out.putNextEntry(new ZipEntry(base));
  FileInputStream in = new FileInputStream(f);
  int b;
  System.out.println(base);
  while ((b = in.read()) != -1) {
  out.write(b);
  }
  in.close();
  }
  }*/

  /*

• unzip
  /
  /public void unZipFileByOpache(ZipFile zipFile, String unZipRoot)
  throws Exception, IOException {
  Enumeration<?> e = zipFile.entries();
  ZipEntry zipEntry;
  while (e.hasMoreElements()) {
  zipEntry = (ZipEntry) e.nextElement();
  InputStream fis = zipFile.getInputStream(zipEntry);
  if (zipEntry.isDirectory()) {
  } else {
  File file = new File(unZipRoot + File.separator

  • zipEntry.getName());
    System.out.println(unZipRoot + File.separator
  • zipEntry.getName());
    File parentFile = file.getParentFile();
    parentFile.mkdirs();
    FileOutputStream fos = new FileOutputStream(file);
    byte[] b = new byte[1024];
    int len;
    while ((len = fis.read(b, 0, b.length)) != -1) {
    fos.write(b, 0, len);
    }
    fos.close();
    fis.close();
    }
    }
    }

  public void ZipFile(String zipFileName, String inputFileName)
  throws Exception {
  ZipOutputStream out = new ZipOutputStream(new FileOutputStream(
  zipFileName));
  File inputFile = new File(inputFileName);
  zip(out, inputFile, "", true);
  System.out.println("zip done");
  out.close();
  }

  public void unZipFile(String unZipFileName, String unZipPath)
  throws Exception {
  //ZipFile zipFile = new ZipFile(unZipFileName);
  //unZipFileByOpache(zipFile, unZipPath);
  System.out.println("unZip Ok");
  }

  public static void main(String[] args) throws Exception {
  FileZip fileZip = new FileZip();
  // ZipFile("d:/testfile.zip","d:/TTPlayer");
  fileZip.unZipFile("d:/20120206_SLIS_0002_DY2.zip", "d:/");
  }*/

  /**

• unzip file 20190424
• @auther: zhao_anan
• @param unzipRoot

• */
  public void unZipFile(String zipFilename, String unzipRoot)
  throws Exception {
  BufferedOutputStream bos = null;
  FileInputStream fis = new FileInputStream(zipFilename);
  BufferedInputStream bis = new BufferedInputStream(fis);

  ZipInputStream zis = new ZipInputStream(bis);
  ZipEntry entry = null;
  
  int count = 0;
  byte buf[] = new byte[1024];
  
  while ((entry = zis.getNextEntry()) != null) {
  
      if (entry.isDirectory()) {
  
      } else {
          File file = new File(unzipRoot + File.separator
                  + entry.getName());
          File parentFile = file.getParentFile();
          parentFile.mkdirs();
  
          bos = new BufferedOutputStream(new FileOutputStream(file));
          while ((count = zis.read(buf)) != -1) {
              bos.write(buf, 0, count);
          }
          bos.flush();
          bos.close();
      }
  }
  zis.close();

  }
  /**

• zip
• @param zipFilename
• @param unzipRoot

• */
  private void zip(ZipOutputStream out, File f, String base, boolean first)
  throws Exception {
  if (first) {
  if (f.isDirectory()) {
  out.putNextEntry(new ZipEntry("/"));
  base = base + f.getName();
  first = false;
  } else
  base = f.getName();
  }
  if (f.isDirectory()) {
  File[] fl = f.listFiles();
  base = base + "/";
  for (int i = 0; i < fl.length; i++) {
  zip(out, fl[i], base + fl[i].getName(), first);
  }
  } else {
  out.putNextEntry(new ZipEntry(base));
  // FileInputStream in = new FileInputStream(f);
  BufferedReader in = new BufferedReader(new InputStreamReader(
  new FileInputStream(f), "ISO8859_1"));
  int b;
  System.out.println(base);
  while ((b = in.read()) != -1) {
  out.write(b);
  }
  in.close();
  }
  }

  public void zipFile(String zipFileName, String inputFileName)
  throws Exception {
  ZipOutputStream out = new ZipOutputStream(new FileOutputStream(
  zipFileName));
  File inputFile = new File(inputFileName);
  zip(out, inputFile, "", true);
  System.out.println("zip done");
  out.close();
  }

  /**

• zip
• @param zipFilename
• @param unzipRoot

• */
  private void zipList(ZipOutputStream out, String[] fileList, String base)
  throws Exception {
  base = base + "\";
  for (int i = 0; i < fileList.length; i++) {
  //zip(out, , base + fileList[i], first);
  out.putNextEntry(new ZipEntry(fileList[i]));
  BufferedReader in = new BufferedReader(new InputStreamReader(
  new FileInputStream(base + fileList[i]), "ISO8859_1"));
  int b;
  System.out.println(base + fileList[i]);
  while ((b = in.read()) != -1) {
  out.write(b);
  }
  in.close();
  }
  }

  public void zipListFile(String zipFileName, String inputListFiles, String baseurl)
  throws Exception {
  ZipOutputStream out = new ZipOutputStream(new FileOutputStream(
  zipFileName));
  String[] FileList = inputListFiles.split(",");
  zipList(out, FileList, baseurl);
  System.out.println("zip done");
  out.close();
  }

  public static void main(String[] args) {

  //压缩测试
  FileZip tFileZip = new FileZip();
  String tinputFileName = "E:\\temp";
  String baseurl = "E:\\temp";
  String tzipFileName = "E:\\temp.zip";
  String inputListFiles = "application-dev.yml,auto_arrange.yml";
  try {
      //tFileZip.zipFile(tzipFileName, tinputFileName);
      tFileZip.zipListFile(tzipFileName, inputListFiles, baseurl);
      //tFileZip.unZipFile(tzipFileName, baseurl + "unzip");
  } catch (Exception e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
  }

  }
  }