如何使 Java 生成的 zip 文件与 WinZip 生成的 zip 文件相同 [英] How can I make my Java-generated zip file identical to a WinZip-generated one
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问题描述
我有一个类将目录的内容压缩到一个 zip 文件中.我正在使用的代码如下.我遇到的问题是我生成的 zip 文件无法被我加载到的应用程序读取.但是，如果我解压缩正在生成的 zip 文件并使用 WinZip 将其再次压缩，则可以使用该文件.我无法控制加载 zip 的目标应用程序，所以我所能做的就是让我的文件看起来像 WinZip 生成的版本.我已经使用 WinZip 详细诊断功能打开了每个 zip 文件，我可以看到生成的文件中有很多差异，但我不明白哪些可能导致了问题.请参阅问题底部的示例.
I have a class that is zipping a directory's contents into a zip file. The code I'm using is below. The problem I'm having is that the zip file generated by me cannot be read by the application I'm loading it into. However, if I unzip the zip file that's being generated and use WinZip to zip it back up again, the file can be used. I have no control over the target application that's loading the zip so all I can do is make my file look like the WinZip-generated version. I've opened each zip file using the WinZip detailed diagnostics feature and I can see lots of differences in the files produced but I don't understand which ones may be causing the issue. See the bottom of the question for examples.
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());
}
}
所以我在 WinZip 生成的 zip 文件诊断中看到的输出如下:
So the output I see in the resulting zip file diagnostics in WinZip are as follows:
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.
从非工作文件的解压缩中重新压缩的工作文件
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.
很明显，我可以在输出中看到差异，但我不明白为什么所有差异都存在，我也不知道哪个是失败的原因.任何帮助确定为什么我的目标应用程序可能不喜欢 Java 生成的文件都会有很大的帮助.我有一种暗示，原因是 Java 与 WinZip 计算 CRC 并随后添加到存档的方式，但我没有遇到此类问题的经验.我的另一个理论是，这是由于内部文件属性造成的.无法解析的示例将export.xml"显示为二进制数据，但 WinZip 版本将其显示为文本.
So obviously I can see differences here in the outputs but I don't understand why all the differences are there, nor do I know which one is the cause of the failure. Any help in identifying why the Java-generated file might not be liked by my target application would be a great help. I have an inkling that the cause is the way the CRC is calculated by Java vs WinZip and subsequently added to the archive, but I have no experience of this kind of issue. My other theory is that it's due to the internal file attributes. The example that's failing to be parsed shows 'export.xml' as binary data but the WinZip version shows it as text.
推荐答案
我解决了这个问题，但通过使用 org.apache.commons.compress 库 zip 文件现在可用.明天我会再次深入研究它，因为我很想知道有什么区别.同时，这是更新的课程.
I worked around the issue, I don't understand what the root cause was but by using the org.apache.commons.compress library the zip file is now usable. I'll dig into it again tomorrow because I'm curious to know what the difference is. Meanwhile, here's the updated class.
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());
}
}
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