Java ZipoutStream在Android上生成损坏的zip文件

Java ZipoutStream在Android上生成损坏的zip文件,java,android,zipfile,Java,Android,Zipfile,我已经使用zip存档实现了应用程序中用户数据的备份,我正在将数据库和共享首选项文件复制到zip存档,并计算输入文件的MD5校验和,以防止用户修改备份数据 要从archive I将备份文件解压缩到临时目录,请检查校验和,然后将preferences\database文件复制到相应的文件夹中 我的一些用户抱怨该应用程序生成的备份文件已损坏(zip文件确实已损坏) 下面是将所有文件压缩为zip文件的代码: public void backup(String filename) { File f

我已经使用zip存档实现了应用程序中用户数据的备份,我正在将数据库和共享首选项文件复制到zip存档,并计算输入文件的MD5校验和,以防止用户修改备份数据

要从archive I将备份文件解压缩到临时目录,请检查校验和,然后将preferences\database文件复制到相应的文件夹中

我的一些用户抱怨该应用程序生成的备份文件已损坏(zip文件确实已损坏)

下面是将所有文件压缩为zip文件的代码:

public void backup(String filename) {
    File file = new File(getBackupDirectory(), filename);
    FileOutputStream fileOutputStream = null;
    ZipOutputStream stream = null;
    try {
        String settingsMD5 = null;
        String databaseMD5 = null;
        if (file.exists())
            file.delete();
        fileOutputStream = new FileOutputStream(file);
        stream = new ZipOutputStream(new BufferedOutputStream(fileOutputStream));
        File database = getDatabasePath(databaseFileName);
        File dataDirectory = getFilesDir();
        if (dataDirectory != null) {
            File settings = new File(dataDirectory.getParentFile(), "/shared_prefs/" + PREFERENCES_FILENAME);
            settingsMD5 = zipFile("preferences", stream, settings);
        }
        databaseMD5 = zipFile("database.db", stream, database);

        JSONObject jsonObject = new JSONObject();
        try {
            jsonObject.put(META_DATE, new SimpleDateFormat(DATE_FORMAT, Locale.US).format(new Date()));
            jsonObject.put(META_DATABASE, databaseMD5);
            jsonObject.put(META_SHARED_PREFS, settingsMD5);
        } catch (Exception e) {
            e.printStackTrace();
        }

        InputStream metadata = new ByteArrayInputStream(jsonObject.toString().getBytes("UTF-8"));
        zipInputStream(stream, metadata, new ZipEntry("metadata"));
        stream.finish();
        stream.close();
        stream = null;
        return file;
    } catch (FileNotFoundException e) {
     //handling errrors
    } catch (IOException e) {
     //handling errrors
    } 
}

private String zipFile(String name, ZipOutputStream zipStream, File file) throws FileNotFoundException, IOException {
        ZipEntry zipEntry = new ZipEntry(name);
        return zipInputStream(zipStream, new FileInputStream(file), zipEntry);
    }

private String zipInputStream(ZipOutputStream zipStream, InputStream fileInputStream, ZipEntry zipEntry) throws IOException {
    InputStream inputStream = new BufferedInputStream(fileInputStream);
    MessageDigest messageDigest = null;
    try {
        messageDigest = MessageDigest.getInstance("MD5");
        if (messageDigest != null)
            inputStream = new DigestInputStream(inputStream, messageDigest);
    } catch (NoSuchAlgorithmException e) {
    }

    zipStream.putNextEntry(zipEntry);
    inputToOutput(inputStream, zipStream);
    zipStream.closeEntry();
    inputStream.close();

    if (messageDigest != null) {
        return getDigestString(messageDigest.digest());
    }
    return null;
}

private String getDigestString(byte[] digest) {
    StringBuffer hexString = new StringBuffer();
    for (int i = 0; i < digest.length; i++) {
        String hex = Integer.toHexString(0xFF & digest[i]);
        if (hex.length() == 1) {
            hex = new StringBuilder("0").append(hex).toString();
        }
        hexString.append(hex);
    }
    return hexString.toString();
}

private void inputToOutput(InputStream inputStream, OutputStream outputStream) throws IOException {
    byte[] buffer = new byte[BUFFER];
    int count = 0;
    while ((count = inputStream.read(buffer, 0, BUFFER)) != -1) {
        outputStream.write(buffer, 0, count);
    }
}
公共无效备份(字符串文件名){
File File=新文件(getBackupDirectory(),文件名);
FileOutputStream FileOutputStream=null;
ZipOutputStream=null;
试一试{
字符串设置MD5=null;
字符串databaseMD5=null;
if(file.exists())
delete();
fileOutputStream=新的fileOutputStream(文件);
stream=新的ZipoutStream(新的BufferedOutputStream(fileOutputStream));
文件数据库=getDatabasePath(databaseFileName);
File dataDirectory=getFilesDir();
if(dataDirectory!=null){
文件设置=新文件(dataDirectory.getParentFile(),“/shared\u prefs/”+首选项\u FILENAME);
settingsMD5=zipFile(“首选项”、流、设置);
}
databaseMD5=zipFile(“database.db”、流、数据库);
JSONObject JSONObject=新的JSONObject();
试一试{
put(META_DATE,新的SimpleDateFormat(DATE_格式,Locale.US).FORMAT(new DATE());
jsonObject.put(META_数据库,databaseMD5);
jsonObject.put(元共享优先权,设置MD5);
}捕获(例外e){
e、 printStackTrace();
}
InputStream元数据=新的ByteArrayInputStream(jsonObject.toString().getBytes(“UTF-8”);
zipInputStream(流、元数据、新ZipEntry(“元数据”));
stream.finish();
stream.close();
流=空;
返回文件;
}catch(filenotfounde异常){
//处理错误
}捕获(IOE异常){
//处理错误
} 
}
私有字符串zipFile(字符串名称、ZipOutStream zipStream、文件文件)抛出FileNotFoundException、IOException{
ZipEntry ZipEntry=新ZipEntry(名称);
返回zipInputStream(zipStream,新文件输入流(文件),zipEntry);
}
私有字符串zipInputStream(ZipOutStream zipStream、InputStream文件InputStream、ZipEntry ZipEntry)引发IOException{
InputStream InputStream=新的BufferedInputStream(fileInputStream);
MessageDigest=null;
试一试{
messageDigest=messageDigest.getInstance(“MD5”);
if(messageDigest!=null)
inputStream=新摘要inputStream(inputStream,messageDigest);
}捕获(无算法异常){
}
zipStream.putNextEntry(Zippentry);
输入输出(输入流、zipStream);
zipStream.closeEntry();
inputStream.close();
if(messageDigest!=null){
返回getDigestString(messageDigest.digest());
}
返回null;
}
私有字符串getDigestString(字节[]摘要){
StringBuffer hexString=新的StringBuffer();
for(int i=0;i<代码> > p>您可以考虑使用ZIP4J库。我用这个库解决了我遇到的问题(相同的问题-不同的方向)。有些zip文件无法使用本机android实现解码,但可以使用zip4j。您还可以通过使用zip4j进行压缩来解决问题。

这里有一些代码,可以仅使用java标准类将目录压缩到文件中。有了这个,您可以直接呼叫:

ZipUtils.zip(sourceDirectory, targetFile);
ZipUtils.unzip(sourceFile, targetDirectory);
代码:

package com.my.project.utils.zip;
导入java.io.IOException;
导入java.nio.file.FileVisitResult;
导入java.nio.file.Files;
导入java.nio.file.Path;
导入java.nio.file.SimpleFileVisitor;
导入java.nio.file.attribute.BasicFileAttributes;
导入java.util.zip.ZipEntry;
导入java.util.zip.ZipoutStream;
公共类ZipUtils{
公共静态void解压(路径sourceFile,路径targetPath)引发IOException{
try(ZipInputStream zipInStream=newzipinputstream(Files.newInputStream(sourceFile))){
字节[]缓冲区=新字节[1024];
创建目录(targetPath);
ZipEntry条目=null;
而((entry=zipInStream.getNextEntry())!=null){
Path entryPath=targetPath.resolve(entry.getName());
Files.createDirectories(entryPath.getParent());
复制(zipInStream,entryPath);
zipInStream.closeEntry();
}
}
} 
公共静态void zip(路径sourcePath,路径targetFile)引发IOException{
try(zipoutptstream zipOutStream=new zipoutptstream(Files.newOutputStream(targetFile))){
if(Files.isDirectory(sourcePath)){
zipDirectory(zipOutStream,sourcePath);
}否则{
createZipEntry(zipOutStream、sourcePath、sourcePath);
}
}
}
私有静态void zipDirectory(ZipOutStream zip,路径源)引发IOException{
walkFileTree(源代码,新的SimpleFileVisitor(){
@凌驾
公共文件VisitResult preVisitDirectory(路径目录,基本文件属性属性属性)引发IOException{
返回FileVisitResult.CONTINUE;
package com.my.project.utils.zip;

import java.io.IOException;
import java.nio.file.FileVisitResult;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.SimpleFileVisitor;
import java.nio.file.attribute.BasicFileAttributes;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

public class ZipUtils {

    public static void unzip(Path sourceFile, Path targetPath) throws IOException {
        try (ZipInputStream zipInStream = new ZipInputStream(Files.newInputStream(sourceFile))){
            byte[] buffer = new byte[1024];
            Files.createDirectories(targetPath);

            ZipEntry entry = null;

            while ((entry = zipInStream.getNextEntry()) != null){
                Path entryPath = targetPath.resolve(entry.getName());
                Files.createDirectories(entryPath.getParent());
                Files.copy(zipInStream, entryPath);
                zipInStream.closeEntry();
            }
        }
    } 

    public static void zip(Path sourcePath, Path targetFile) throws IOException {
        try (ZipOutputStream zipOutStream = new ZipOutputStream(Files.newOutputStream(targetFile))){
            if (Files.isDirectory(sourcePath)){
                zipDirectory(zipOutStream, sourcePath);
            } else {
                createZipEntry(zipOutStream, sourcePath, sourcePath);
            }
        }
    }

    private static void zipDirectory(ZipOutputStream zip, Path source) throws IOException {
        Files.walkFileTree(source, new SimpleFileVisitor<Path>(){
            @Override
            public FileVisitResult preVisitDirectory(Path dir, BasicFileAttributes attrs) throws IOException {
                return FileVisitResult.CONTINUE;
            }           
            @Override
            public FileVisitResult visitFile(Path path, BasicFileAttributes attrs) throws IOException {
                createZipEntry(zip, source, path);
                return FileVisitResult.CONTINUE;
            }
        });
    }    

    private static void createZipEntry(ZipOutputStream zip, Path sourcePath, Path path) throws IOException {
        ZipEntry entry = new ZipEntry(sourcePath.relativize(path).toString());
        zip.putNextEntry(entry);
        Files.copy(path,zip);
        zip.closeEntry();
    }
}