Comment puis-je rendre mon fichier zip généré par Java identique à un fichier généré par WinZip
J'ai une classe qui compresse le contenu d'un répertoire dans un fichier zip. Le code que j'utilise est ci-dessous. Le problème que j'ai est que le fichier zip généré par moi ne peut pas être lu par l'application dans laquelle je le charge. Cependant, si je décompresse le fichier zip en cours de génération et utilise WinZip pour le compresser à nouveau, le fichier peut être utilisé. Je n'ai aucun contrôle sur l'application cible qui charge le zip, donc tout ce que je peux faire est de faire ressembler mon fichier à la version générée par WinZip. J'ai ouvert chaque fichier zip en utilisant la fonction de diagnostic détaillé WinZip et je peux voir beaucoup de différences dans les fichiers produits, mais je ne comprends pas lesquels peuvent être à l'origine du problème. Voir le bas de la question pour des exemples.
package com.mycompany.utils;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;
import org.apache.log4j.Logger;
public class FileZipper {
private static final Logger LOGGER = Logger.getLogger(FileZipper.class);
private String destinationZipFile;
private String sourceDirectory;
List<String> fileList;
private File zipFile;
public File getZipFile() {
return zipFile;
}
/**
* Zips a source directory into the destination zip file
*
* @param source
* @param destination
*/
FileZipper(String source, String destination) {
LOGGER.info("Zipping source directory: "+source);
LOGGER.info("To destination zip file: "+destination);
this.destinationZipFile = destination;
this.sourceDirectory = source;
fileList = new ArrayList<String>();
generateFileList(new File(sourceDirectory));
compressDirectoryContentsToZip(sourceDirectory, destinationZipFile);
}
/**
* Traverse a directory and get all files, and add the file into fileList
*
* @param node
* file or directory
*/
public void generateFileList(File node) {
// add file only
if (node.isFile()) {
fileList.add(generateZipEntry(node.getAbsoluteFile().toString()));
}
if (node.isDirectory()) {
if(node.toString() != sourceDirectory) {
fileList.add(generateZipEntry(node.getAbsoluteFile().toString()));
}
String[] subNodes = node.list();
for (String filename : subNodes) {
generateFileList(new File(node, filename));
}
}
}
/**
* Compress a directory to a zip file
* @param sourceDirectory
* @param destinationZipFile
*/
public void compressDirectoryContentsToZip(String sourceDirectory,
String destinationZipFile) {
this.zipFile = new File(destinationZipFile);
byte[] buffer = new byte[4096];
try {
FileOutputStream fos = new FileOutputStream(destinationZipFile);
BufferedOutputStream bos = new BufferedOutputStream(fos);
ZipOutputStream zos = new ZipOutputStream(bos);
zos.setMethod(ZipOutputStream.DEFLATED);
LOGGER.info("Zipping to : " + destinationZipFile);
for (String entry : this.fileList) {
long fileSizeInBytes = new File(sourceDirectory +
File.separator + entry).length();
if(new File(sourceDirectory + File.separator + entry).isFile()) {
LOGGER.info("File Added : " + entry + " ("+String.valueOf(fileSizeInBytes)+" bytes)");
ZipEntry ze = new ZipEntry(entry);
zos.putNextEntry(ze);
FileInputStream in = new FileInputStream(sourceDirectory
+ File.separator + entry);
int len;
while ((len = in.read(buffer)) > 0) {
zos.write(buffer, 0, len);
}
in.close();
zos.closeEntry();
} else if(new File(sourceDirectory + File.separator + entry).isDirectory()) {
LOGGER.info("Directory Added : " + entry);
ZipEntry ze = new ZipEntry(entry+File.separator);
zos.putNextEntry(ze);
zos.closeEntry();
} else {
LOGGER.warn("Not a file or directory: "+entry);
}
}
zos.closeEntry();
zos.close();
LOGGER.info("Zipping completed successfully");
} catch (IOException ex) {
LOGGER.error(ex);
System.exit(1);
}
LOGGER.info("Generated zip file: "+ destinationZipFile);
}
/**
* Format the filename for archiving by removing the path
* of the source directory
*
* @param file
* @return
*/
private String generateZipEntry(String file) {
LOGGER.debug("Stripping '"+file+"' to '"
+file.substring(sourceDirectory.length() + 1, file.length())+"'");
return file.substring(sourceDirectory.length() + 1, file.length());
}
}
Donc, la sortie que je vois dans les diagnostics de fichier zip résultants dans WinZip est la suivante:
Fichier non fonctionnel
Archive: C:\Users\conor\Desktop\dp-export-2\dp-export-2.zip 3573 bytes 2014-11-04 20:03:22
Current Location part 1 offset 3551
End central directory record PK0506 (4+18)
==========================================
location of end-of-central-dir record: 3551 (0x00000ddf) bytes
part number of this part (0000): 1
part number of start of central dir (0000): 1
number of entries in central dir in this part: 1
total number of entries in central dir: 1
size of central dir: 56 (0x00000038) bytes
relative offset of central dir: 3495 (0x00000da7) bytes
zipfile comment length: 0
Current Location part 1 offset 3495
Central directory entry PK0102 (4+42): #1
======================================
part number in which file begins (0000): 1
relative offset of local header: 0 (0x00000000) bytes
version made by operating system (00): MS-DOS, OS/2, NT FAT
version made by zip software (20): 2.0
operat. system version needed to extract (00): MS-DOS, OS/2, NT FAT
unzip software version needed to extract (20): 2.0
general purpose bit flag (0x0808) (bit 15..0): 0000.1000 0000.1000
file security status (bit 0): not encrypted
extended local header (bit 3): yes
UTF-8 names (bit 11): yes
compression method (08): deflated
compression sub-type (deflation): normal
file last modified on (0x00004564 0x0000a06a): 2014-11-04 20:03:20
32-bit CRC value: 0x07d797c8
compressed size: 3439 bytes
uncompressed size: 24021 bytes
length of filename: 10 characters
length of extra field: 0 bytes
length of file comment: 0 characters
internal file attributes: 0x0000
apparent file type: binary
external file attributes: 0x00000000
non-MSDOS external file attributes: 0x000000
MS-DOS file attributes (0x00): none
filename: export.xml
Current Location part 1 offset 0
Local directory entry PK0304 (4+26): #1
------------------------------------
operat. system version needed to extract (00): MS-DOS, OS/2, NT FAT
unzip software version needed to extract (20): 2.0
general purpose bit flag (0x0808) (bit 15..0): 0000.1000 0000.1000
file security status (bit 0): not encrypted
extended local header (bit 3): yes
UTF-8 names (bit 11): yes
compression method (08): deflated
compression sub-type (deflation): normal
file last modified on (0x00004564 0x0000a06a): 2014-11-04 20:03:20
32-bit CRC value: 0x00000000
compressed size: 0 bytes
uncompressed size: 0 bytes
note: "real" crc and sizes are in the extended local header
length of filename: 10 characters
length of extra field: 0 bytes
filename: export.xml
Testing export.xml OK
Current Location part 1 offset 3479
Extended local dir entry PK0708 (4+12): #1
---------------------------------------
32-bit CRC value: 0x07d797c8
compressed size: 3439 bytes
uncompressed size: 24021 bytes
No errors detected in compressed data of C:\Users\conor\Desktop\dp-export-2\dp-export-2.zip.
Fichier de travail qui a été re-compressé à partir du décompressage du fichier non fonctionnel
Archive: C:\Users\conor\Desktop\dp-export-2\dp-export-2b.zip 3564 bytes 2014-11-04 20:04:46
Current Location part 1 offset 3542
End central directory record PK0506 (4+18)
==========================================
location of end-of-central-dir record: 3542 (0x00000dd6) bytes
part number of this part (0000): 1
part number of start of central dir (0000): 1
number of entries in central dir in this part: 1
total number of entries in central dir: 1
size of central dir: 92 (0x0000005c) bytes
relative offset of central dir: 3450 (0x00000d7a) bytes
zipfile comment length: 0
Current Location part 1 offset 3450
Central directory entry PK0102 (4+42): #1
======================================
part number in which file begins (0000): 1
relative offset of local header: 0 (0x00000000) bytes
version made by operating system (00): MS-DOS, OS/2, NT FAT
version made by zip software (20): 2.0
operat. system version needed to extract (00): MS-DOS, OS/2, NT FAT
unzip software version needed to extract (20): 2.0
general purpose bit flag (0x0002) (bit 15..0): 0000.0000 0000.0010
file security status (bit 0): not encrypted
extended local header (bit 3): no
compression method (08): deflated
compression sub-type (deflation): maximum
file last modified on (0x00004564 0x0000a06a): 2014-11-04 20:03:20
32-bit CRC value: 0x07d797c8
compressed size: 3410 bytes
uncompressed size: 24021 bytes
length of filename: 10 characters
length of extra field: 36 bytes
length of file comment: 0 characters
internal file attributes: 0x0001
apparent file type: text
external file attributes: 0x00000020
non-MSDOS external file attributes: 0x000000
MS-DOS file attributes (0x20): arc
filename: export.xml
extra field 0x000a (PKWARE Win32 Filetimes), 4 header and 32 data bytes:
The Extended Timestamps are:
Creation Date: 2014-11-04 20:03:20
Last Modified Date: 2014-11-04 20:03:20
Last Accessed Date: 2014-11-04 20:03:20
Current Location part 1 offset 0
Local directory entry PK0304 (4+26): #1
------------------------------------
operat. system version needed to extract (00): MS-DOS, OS/2, NT FAT
unzip software version needed to extract (20): 2.0
general purpose bit flag (0x0002) (bit 15..0): 0000.0000 0000.0010
file security status (bit 0): not encrypted
extended local header (bit 3): no
compression method (08): deflated
compression sub-type (deflation): maximum
file last modified on (0x00004564 0x0000a06a): 2014-11-04 20:03:20
32-bit CRC value: 0x07d797c8
compressed size: 3410 bytes
uncompressed size: 24021 bytes
length of filename: 10 characters
length of extra field: 0 bytes
filename: export.xml
Testing export.xml OK
No errors detected in compressed data of C:\Users\conor\Desktop\dp-export-2\dp-export-2b.zip.
Donc évidemment je peux voir différences dans les résultats, mais je ne comprends pas pourquoi toutes les différences sont là, je ne sais laquelle est la cause de l'échec. Toute aide pour identifier pourquoi le fichier généré par Java pourrait ne pas être aimé par mon application cible serait d'une grande aide. J'ai une idée que la cause est la façon dont le CRC est calculé par Java vs WinZip et ajouté par la suite à l'archive, mais je n'ai aucune expérience de ce genre de problème. Mon autre théorie est que c'est dû au fichier interne attribut. L'exemple qui ne parvient pas à être analysé montre 'export.xml ' en tant que données binaires mais la version WinZip l'affiche sous forme de texte.
4
Author: conorgriffin, 2014-11-04
1 answers
J'ai contourné le problème, je ne comprends pas quelle était la cause première mais en utilisant l'organisation .Apache.commun.compresser bibliothèque, le fichier zip est maintenant utilisable. Je vais creuser à nouveau demain parce que je suis curieux de savoir quelle est la différence. En attendant, voici la classe mise à jour.
package com.mycompany.utils;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.commons.compress.archivers.zip.ZipArchiveEntry;
import org.apache.commons.compress.archivers.zip.ZipArchiveOutputStream;
import org.apache.log4j.Logger;
public class FileZipper {
private static final Logger LOGGER = Logger.getLogger(OldFileZipper.class);
private String destinationZipFile;
private String sourceDirectory;
List<String> fileList;
private File zipFile;
public File getZipFile() {
return zipFile;
}
/**
* Zips a source directory into the destination zip file
*
* @param source
* @param destination
*/
FileZipper(String source, String destination) {
LOGGER.info("Zipping source directory: "+source);
LOGGER.info("To destination zip file: "+destination);
this.destinationZipFile = destination;
this.sourceDirectory = source;
fileList = new ArrayList<String>();
generateFileList(new File(sourceDirectory));
compressDirectoryContentsToZip(sourceDirectory, destinationZipFile);
}
/**
* Traverse a directory and get all files, and add the file into fileList
*
* @param node
* file or directory
*/
public void generateFileList(File node) {
// add file only
if (node.isFile()) {
fileList.add(generateZipEntry(node.getAbsoluteFile().toString()));
}
if (node.isDirectory()) {
if(node.toString() != sourceDirectory) {
fileList.add(generateZipEntry(node.getAbsoluteFile().toString()));
}
String[] subNodes = node.list();
for (String filename : subNodes) {
generateFileList(new File(node, filename));
}
}
}
/**
* Compress a directory to a zip file
* @param sourceDirectory
* @param destinationZipFile
*/
public void compressDirectoryContentsToZip(String sourceDirectory, String destinationZipFile) {
this.zipFile = new File(destinationZipFile);
byte[] buffer = new byte[4096];
try {
FileOutputStream fos = new FileOutputStream(destinationZipFile);
BufferedOutputStream bos = new BufferedOutputStream(fos);
ZipArchiveOutputStream zos = new ZipArchiveOutputStream(bos);
zos.setMethod(ZipArchiveOutputStream.DEFLATED);
zos.setLevel(0);
LOGGER.info("Zipping to : " + destinationZipFile);
for (String entry : this.fileList) {
long fileSizeInBytes = new File(sourceDirectory + File.separator + entry).length();
if(new File(sourceDirectory + File.separator + entry).isFile()) {
LOGGER.info("File Added : " + entry + " ("+String.valueOf(fileSizeInBytes)+" bytes)");
ZipArchiveEntry ze = new ZipArchiveEntry(entry);
zos.putArchiveEntry(ze);
FileInputStream in = new FileInputStream(sourceDirectory
+ File.separator + entry);
int len;
while ((len = in.read(buffer)) > 0) {
zos.write(buffer, 0, len);
}
in.close();
zos.closeArchiveEntry();
} else if(new File(sourceDirectory + File.separator + entry).isDirectory()) {
LOGGER.info("Directory Added : " + entry);
ZipArchiveEntry ze = new ZipArchiveEntry(entry+File.separator);
zos.putArchiveEntry(ze);
zos.closeArchiveEntry();
} else {
LOGGER.warn("Not a file or directory: "+entry);
}
}
zos.close();
LOGGER.info("Zipping completed successfully");
} catch (IOException ex) {
LOGGER.error(ex);
System.exit(1);
}
LOGGER.info("Generated zip file: "+ destinationZipFile);
}
/**
* Format the filename for archiving by removing the path
* of the source directory
*
* @param file
* @return
*/
private String generateZipEntry(String file) {
LOGGER.debug("Stripping '"+file+"' to '"+file.substring(sourceDirectory.length() + 1, file.length())+"'");
return file.substring(sourceDirectory.length() + 1, file.length());
}
}
2
Author: conorgriffin, 2014-11-04 23:16:11