在Java中创建zip存档
我有一个由7zip程序创建的文件。我用了deflate方法来压缩它。现在我想在在Java中创建zip存档,java,zip,Java,Zip,我有一个由7zip程序创建的文件。我用了deflate方法来压缩它。现在我想在java中创建相同的归档（使用相同的MD5sum）。当我创建zip文件时，我使用了我在互联网上找到的算法，但是当我用这种方法创建zip文件时，压缩的大小大于未压缩文件的大小，所以发生了什么？这不是一个非常有用的压缩。那个么我怎样才能创建和我用7zip程序创建的zip文件完全相同的zip文件呢？如果有帮助的话，我有关于我在7zip程序中创建的zip文件的所有信息。只是为了澄清一下，您在7zip中使用了zip算法作为原始文
java您是否正在尝试解压缩ZIP文件，更改其中的文件，然后重新压缩它，使其具有相同的MD5哈希？散列是为了阻止您这样做 ZipoutStream有几种方法来调整压缩： 设置默认的压缩方法 以后的条目。此默认值 将在压缩时使用 方法未指定为 单个ZIP文件条目，并且 最初设置为放气 设置的压缩级别 已平仓的后续分录。 默认设置为默认压缩。级别-压缩级别（0-9） 当您在以下内容之后添加时：
ZipOutputStream zos = new ZipOutputStream(new FileOutputStream(target));
zos.setMethod( ZipOutputStream.DEFLATED );
zos.setLevel( 5 );
...
它不改进压缩吗？要从同一源文件生成两个相同的zip文件（包括相同的md5sum），我建议使用相同的zip实用程序——要么始终使用相同的Java程序，要么始终使用7zip
// simplified code for zip creation in java
import java.io.*;
import java.util.zip.*;
public class ZipCreateExample {
public static void main(String[] args) throws Exception {
// input file
FileInputStream in = new FileInputStream("F:/sometxt.txt");
// out put file
ZipOutputStream out = new ZipOutputStream(new FileOutputStream("F:/tmp.zip"));
// name the file inside the zip file
out.putNextEntry(new ZipEntry("zippedjava.txt"));
// buffer size
byte[] b = new byte[1024];
int count;
while ((count = in.read(b)) > 0) {
out.write(b, 0, count);
}
out.close();
in.close();
}
}
$ ls tst1/
foo.tar
$ cp -r tst1 tst2
$ ( cd tst1; zip foo.zip foo.tar ) ; ( cd tst2; zip foo.zip foo.tar ) ; md5sum tst?/foo.zip
updating: foo.tar (deflated 20%)
updating: foo.tar (deflated 20%)
359b82678a2e17c1ddbc795ceeae7b60 tst1/foo.zip
b55c33c0414ff987597d3ef9ad8d1d08 tst2/foo.zip
不同的文件名和路径也会出现同样的问题，即使zip中的文件是相同的。这里有一个函数，您可以传递绝对路径，它将创建一个与目录同名的zip文件（在该目录下，您希望压缩所有子文件夹和文件，所有内容！！）成功时返回true，异常时返回false（如果有）
public class FileUtil {
final static int BUFFER = 2048;
private static Logger log = Logger.getLogger(FileUtil.class);
public static boolean createZipArchive(String srcFolder) {
try {
BufferedInputStream origin = null;
FileOutputStream dest = new FileOutputStream(new File(srcFolder+ ".zip"));
ZipOutputStream out = new ZipOutputStream(new BufferedOutputStream(dest));
byte data[] = new byte[BUFFER];
File subDir = new File(srcFolder);
String subdirList[] = subDir.list();
for(String sd:subdirList)
{
// get a list of files from current directory
File f = new File(srcFolder+"/"+sd);
if(f.isDirectory())
{
String files[] = f.list();
for (int i = 0; i < files.length; i++) {
System.out.println("Adding: " + files[i]);
FileInputStream fi = new FileInputStream(srcFolder + "/"+sd+"/" + files[i]);
origin = new BufferedInputStream(fi, BUFFER);
ZipEntry entry = new ZipEntry(sd +"/"+files[i]);
out.putNextEntry(entry);
int count;
while ((count = origin.read(data, 0, BUFFER)) != -1) {
out.write(data, 0, count);
out.flush();
}
}
}
else //it is just a file
{
FileInputStream fi = new FileInputStream(f);
origin = new BufferedInputStream(fi, BUFFER);
ZipEntry entry = new ZipEntry(sd);
out.putNextEntry(entry);
int count;
while ((count = origin.read(data, 0, BUFFER)) != -1) {
out.write(data, 0, count);
out.flush();
}
}
}
origin.close();
out.flush();
out.close();
} catch (Exception e) {
log.info("createZipArchive threw exception: " + e.getMessage());
return false;
}
return true;
}
}
公共类FileUtil{
最终静态int缓冲区=2048；
私有静态记录器log=Logger.getLogger（FileUtil.class）；
公共静态布尔createZipArchive（字符串文件夹）{
试一试{
BufferedInputStream原点=null；
FileOutputStream dest=newfileoutputstream（新文件（srcFolder+“.zip”）；
ZipOutputStream out=新的zipoutpstream（新的缓冲输出流（dest））；
字节数据[]=新字节[缓冲区]；
File subDir=新文件（srcFolder）；
字符串subdirList[]=subDir.list（）；
for（字符串sd:子列表）
{
//从当前目录获取文件列表
文件f=新文件（srcFolder+“/”+sd）；
if（f.isDirectory（））
{
字符串文件[]=f.list（）；
对于（int i=0；ipackage com.util;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import java.util.zip.ZipOutputStream;
/**
* @author dinesh.lomte
*
*/
public class ZipUtil {
/**
*
* @param source
* @param destination
*/
public static void unZip(String source, String destination) {
String method = "unZip(String source, String destination)";
ZipInputStream zipInputStream = null;
try {
// Creating the ZipInputStream instance from the source file
zipInputStream = new ZipInputStream(new FileInputStream(source));
// Getting the zipped file list entry
ZipEntry zipEntry = zipInputStream.getNextEntry();
// Iterating through the file list entry
while (zipEntry != null) {
String fileName = zipEntry.getName();
File file = new File(new StringBuilder(destination)
.append(File.separator)
.append(AppUtil.getFileNameWithoutExtension(
AppUtil.getNameFromPath(source)))
.append(File.separator).append(fileName).toString());
// Creating non existing folders to avoid any FileNotFoundException
// for compressed folder
new File(file.getParent()).mkdirs();
FileOutputStream fileOutputStream = new FileOutputStream(file);
byte[] buffer = new byte[1024];
int length;
while ((length = zipInputStream.read(buffer)) > 0) {
fileOutputStream.write(buffer, 0, length);
}
fileOutputStream.close();
zipEntry = zipInputStream.getNextEntry();
}
} catch (IOException iOException) {
System.out.println("Failed to unzip the ''{0}'' file located in ''{1}'' folder. Due to, {2}");
} finally {
// Validating if zipInputStream instance in not null
if (zipInputStream != null) {
try {
zipInputStream.closeEntry();
zipInputStream.close();
} catch (IOException iOException) {
}
}
}
}
/**
* Traverse a directory from the source folder location and get all files,
* and add the file into files list.
*
* @param node
*/
public static void generateFileList(
String source, File node, List<String> files) {
// Validating if the node is a file
if (node.isFile()) {
files.add(generateZipEntry(
source, node.getPath().toString()));
}
// Validating if the node is a directory
if (node.isDirectory()) {
String[] subNote = node.list();
for (String filename : subNote) {
generateFileList(source, new File(node, filename), files);
}
}
}
/**
* Format the file path to zip
* @param source
* @param file
* @return
*/
private static String generateZipEntry(String source, String file) {
return file.substring(source.length(), file.length());
}
/**
*
* @param source
* @param destination
*/
public static void zip(String source, String destination) {
String method = "zip(String source, String destination)";
ZipOutputStream zipOutputStream = null;
try {
// Creating the zipOutputStream instance
zipOutputStream = new ZipOutputStream(
new FileOutputStream(destination));
List<String> files = new ArrayList<>();
generateFileList(source, new File(source), files);
// Iterating the list of file(s) to zip/compress
for (String file : files) {
// Adding the file(s) to the zip
ZipEntry zipEntry = new ZipEntry(file);
zipOutputStream.putNextEntry(zipEntry);
FileInputStream fileInputStream = new FileInputStream(
new StringBuilder(source).append(File.separator)
.append(file).toString());
int length;
byte[] buffer = new byte[1024];
while ((length = fileInputStream.read(buffer)) > 0) {
zipOutputStream.write(buffer, 0, length);
}
// Closing the fileInputStream instance
fileInputStream.close();
// De-allocating the memory by assigning the null value
fileInputStream = null;
}
} catch (IOException iOException) {
System.out.println("Failed to zip the file(s) located in ''{0}'' folder. Due to, {1}");
} finally {
// Validating if zipOutputStream instance in not null
if (zipOutputStream != null) {
try {
zipOutputStream.closeEntry();
zipOutputStream.close();
} catch (IOException iOException) {
}
}
}
}
}
package com.util；
导入java.io.File；
导入java.io.FileInputStream；
导入java.io.FileOutputStream；
导入java.io.IOException；
导入java.util.ArrayList；
导入java.util.Date；
导入java.util.List；
导入java.util.zip.ZipEntry；
导入java.util.zip.ZipInputStream；
导入java.util.zip.ZipoutStream；
/**
*@author dinesh.lomte
*
*/
公共类ZipUtil{
/**
*
*@param源
*@param destina
package comm;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;*emphasized text*
import java.io.IOException;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;
public class Zip1 {
public static void main( String[] args )
{
byte[] buffer = new byte[1024];
try{
File f= new File("E:\\");
f.mkdirs();
File origFile= new File(f,"MyZipFile2.zip");
FileOutputStream fos = new FileOutputStream(origFile);
ZipOutputStream zos = new ZipOutputStream(fos);
ZipEntry ze= new ZipEntry("test.pdf");
zos.putNextEntry(ze);
FileInputStream in = new FileInputStream("D:\\Test.pdf");
int len;
while ((len = in.read(buffer)) > 0) {
zos.write(buffer, 0, len);
}
in.close();
zos.closeEntry();
//remember close it
zos.close();
System.out.println("Done");
}catch(IOException ex){
ex.printStackTrace();
}
}
}
package com.util;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import java.util.zip.ZipOutputStream;
/**
* @author dinesh.lomte
*
*/
public class ZipUtil {
/**
*
* @param source
* @param destination
*/
public static void unZip(String source, String destination) {
String method = "unZip(String source, String destination)";
ZipInputStream zipInputStream = null;
try {
// Creating the ZipInputStream instance from the source file
zipInputStream = new ZipInputStream(new FileInputStream(source));
// Getting the zipped file list entry
ZipEntry zipEntry = zipInputStream.getNextEntry();
// Iterating through the file list entry
while (zipEntry != null) {
String fileName = zipEntry.getName();
File file = new File(new StringBuilder(destination)
.append(File.separator)
.append(AppUtil.getFileNameWithoutExtension(
AppUtil.getNameFromPath(source)))
.append(File.separator).append(fileName).toString());
// Creating non existing folders to avoid any FileNotFoundException
// for compressed folder
new File(file.getParent()).mkdirs();
FileOutputStream fileOutputStream = new FileOutputStream(file);
byte[] buffer = new byte[1024];
int length;
while ((length = zipInputStream.read(buffer)) > 0) {
fileOutputStream.write(buffer, 0, length);
}
fileOutputStream.close();
zipEntry = zipInputStream.getNextEntry();
}
} catch (IOException iOException) {
System.out.println("Failed to unzip the ''{0}'' file located in ''{1}'' folder. Due to, {2}");
} finally {
// Validating if zipInputStream instance in not null
if (zipInputStream != null) {
try {
zipInputStream.closeEntry();
zipInputStream.close();
} catch (IOException iOException) {
}
}
}
}
/**
* Traverse a directory from the source folder location and get all files,
* and add the file into files list.
*
* @param node
*/
public static void generateFileList(
String source, File node, List<String> files) {
// Validating if the node is a file
if (node.isFile()) {
files.add(generateZipEntry(
source, node.getPath().toString()));
}
// Validating if the node is a directory
if (node.isDirectory()) {
String[] subNote = node.list();
for (String filename : subNote) {
generateFileList(source, new File(node, filename), files);
}
}
}
/**
* Format the file path to zip
* @param source
* @param file
* @return
*/
private static String generateZipEntry(String source, String file) {
return file.substring(source.length(), file.length());
}
/**
*
* @param source
* @param destination
*/
public static void zip(String source, String destination) {
String method = "zip(String source, String destination)";
ZipOutputStream zipOutputStream = null;
try {
// Creating the zipOutputStream instance
zipOutputStream = new ZipOutputStream(
new FileOutputStream(destination));
List<String> files = new ArrayList<>();
generateFileList(source, new File(source), files);
// Iterating the list of file(s) to zip/compress
for (String file : files) {
// Adding the file(s) to the zip
ZipEntry zipEntry = new ZipEntry(file);
zipOutputStream.putNextEntry(zipEntry);
FileInputStream fileInputStream = new FileInputStream(
new StringBuilder(source).append(File.separator)
.append(file).toString());
int length;
byte[] buffer = new byte[1024];
while ((length = fileInputStream.read(buffer)) > 0) {
zipOutputStream.write(buffer, 0, length);
}
// Closing the fileInputStream instance
fileInputStream.close();
// De-allocating the memory by assigning the null value
fileInputStream = null;
}
} catch (IOException iOException) {
System.out.println("Failed to zip the file(s) located in ''{0}'' folder. Due to, {1}");
} finally {
// Validating if zipOutputStream instance in not null
if (zipOutputStream != null) {
try {
zipOutputStream.closeEntry();
zipOutputStream.close();
} catch (IOException iOException) {
}
}
}
}
}