140

我需要一个小代码片段，它可以从给定的 .zip 文件中解压缩几个文件，并根据它们在压缩文件中的格式给出单独的文件。请发布您的知识并帮助我。

4

15 回答 15

148

对peno的版本进行了一些优化。性能的提升是可以察觉的。

private boolean unpackZip(String path, String zipname)
{       
     InputStream is;
     ZipInputStream zis;
     try 
     {
         String filename;
         is = new FileInputStream(path + zipname);
         zis = new ZipInputStream(new BufferedInputStream(is));          
         ZipEntry ze;
         byte[] buffer = new byte[1024];
         int count;

         while ((ze = zis.getNextEntry()) != null) 
         {
             filename = ze.getName();

             // Need to create directories if not exists, or
             // it will generate an Exception...
             if (ze.isDirectory()) {
                File fmd = new File(path + filename);
                fmd.mkdirs();
                continue;
             }

             FileOutputStream fout = new FileOutputStream(path + filename);

             while ((count = zis.read(buffer)) != -1) 
             {
                 fout.write(buffer, 0, count);             
             }

             fout.close();               
             zis.closeEntry();
         }

         zis.close();
     } 
     catch(IOException e)
     {
         e.printStackTrace();
         return false;
     }

    return true;
}
于 2012-06-12T13:37:53.613 回答
106

基于 Vasily Sochinsky 的回答稍作调整并进行了小修复：

public static void unzip(File zipFile, File targetDirectory) throws IOException {
    ZipInputStream zis = new ZipInputStream(
            new BufferedInputStream(new FileInputStream(zipFile)));
    try {
        ZipEntry ze;
        int count;
        byte[] buffer = new byte[8192];
        while ((ze = zis.getNextEntry()) != null) {
            File file = new File(targetDirectory, ze.getName());
            File dir = ze.isDirectory() ? file : file.getParentFile();
            if (!dir.isDirectory() && !dir.mkdirs())
                throw new FileNotFoundException("Failed to ensure directory: " +
                        dir.getAbsolutePath());
            if (ze.isDirectory())
                continue;
            FileOutputStream fout = new FileOutputStream(file);
            try {
                while ((count = zis.read(buffer)) != -1)
                    fout.write(buffer, 0, count);
            } finally {
                fout.close();
            }
            /* if time should be restored as well
            long time = ze.getTime();
            if (time > 0)
                file.setLastModified(time);
            */
        }
    } finally {
        zis.close();
    }
}

显着差异

  • public static- 这是一种可以在任何地方使用的静态实用程序方法。
  • 2 个File参数，因为String是 :/ 用于文件，并且之前无法指定要提取 zip 文件的位置。还有path + filename串联> https://stackoverflow.com/a/412495/995891
  • throws- 因为赶晚了- 如果真的对它们不感兴趣，请添加尝试捕捉。
  • 实际上确保在所有情况下都存在所需的目录。并非每个 zip 都在文件条目之前包含所有必需的目录条目。这有两个潜在的错误：
    • 如果 zip 包含一个空目录，而不是生成的目录，则存在一个文件，这将被忽略。的返回值mkdirs()很重要。
    • 可能会在不包含目录的 zip 文件上崩溃。
  • 增加写入缓冲区大小，这应该会提高性能。存储通常以 4k 块为单位，以较小的块写入通常比必要的要慢。
  • 使用 的魔法finally来防止资源泄漏。

所以

unzip(new File("/sdcard/pictures.zip"), new File("/sdcard"));

应该做相当于原来的

unpackZip("/sdcard/", "pictures.zip")
于 2014-11-20T22:18:12.257 回答
26

这是我使用的解压缩方法：

private boolean unpackZip(String path, String zipname)
{       
     InputStream is;
     ZipInputStream zis;
     try 
     {
         is = new FileInputStream(path + zipname);
         zis = new ZipInputStream(new BufferedInputStream(is));          
         ZipEntry ze;

         while((ze = zis.getNextEntry()) != null) 
         {
             ByteArrayOutputStream baos = new ByteArrayOutputStream();
             byte[] buffer = new byte[1024];
             int count;

             String filename = ze.getName();
             FileOutputStream fout = new FileOutputStream(path + filename);

             // reading and writing
             while((count = zis.read(buffer)) != -1) 
             {
                 baos.write(buffer, 0, count);
                 byte[] bytes = baos.toByteArray();
                 fout.write(bytes);             
                 baos.reset();
             }

             fout.close();               
             zis.closeEntry();
         }

         zis.close();
     } 
     catch(IOException e)
     {
         e.printStackTrace();
         return false;
     }

    return true;
}
于 2011-09-14T17:47:20.203 回答
17

Kotlin 方式

//FileExt.kt

data class ZipIO (val entry: ZipEntry, val output: File)

fun File.unzip(unzipLocationRoot: File? = null) {

    val rootFolder = unzipLocationRoot ?: File(parentFile.absolutePath + File.separator + nameWithoutExtension)
    if (!rootFolder.exists()) {
       rootFolder.mkdirs()
    }

    ZipFile(this).use { zip ->
        zip
        .entries()
        .asSequence()
        .map {
            val outputFile = File(rootFolder.absolutePath + File.separator + it.name)
            ZipIO(it, outputFile)
        }
        .map {
            it.output.parentFile?.run{
                if (!exists()) mkdirs()
            }
            it
        }
        .filter { !it.entry.isDirectory }
        .forEach { (entry, output) ->
            zip.getInputStream(entry).use { input ->
                output.outputStream().use { output ->
                    input.copyTo(output)
                }
            }
        }
    }

}

用法

val zipFile = File("path_to_your_zip_file")
file.unzip()
于 2018-06-22T15:07:34.990 回答
13

Android 有内置的 Java API。查看java.util.zip包。

ZipInputStream类是您应该研究的。从 ZipInputStream 中读取 ZipEntry 并将其转储到文件系统/文件夹中。检查类似的示例以压缩成 zip文件。

于 2010-08-01T17:32:16.073 回答
7

虽然已经在这里的答案运行良好，但我发现它们比我希望的要慢一些。相反，我使用了 zip4j，我认为这是最好的解决方案，因为它的速度很快。它还允许不同的压缩量选项，我发现这很有用。

于 2013-05-23T06:07:01.370 回答
7

使用以下类

    import java.io.BufferedOutputStream;
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.FileOutputStream;
    import java.util.zip.ZipEntry;
    import java.util.zip.ZipInputStream;
    import android.util.Log;

    public class DecompressFast {



 private String _zipFile; 
  private String _location; 
 
  public DecompressFast(String zipFile, String location) { 
    _zipFile = zipFile; 
    _location = location; 
 
    _dirChecker(""); 
  } 
 
  public void unzip() { 
    try  { 
      FileInputStream fin = new FileInputStream(_zipFile); 
      ZipInputStream zin = new ZipInputStream(fin); 
      ZipEntry ze = null; 
      while ((ze = zin.getNextEntry()) != null) { 
        Log.v("Decompress", "Unzipping " + ze.getName()); 
 
        if(ze.isDirectory()) { 
          _dirChecker(ze.getName()); 
        } else { 
          FileOutputStream fout = new FileOutputStream(_location + ze.getName()); 
         BufferedOutputStream bufout = new BufferedOutputStream(fout);
          byte[] buffer = new byte[1024];
          int read = 0;
          while ((read = zin.read(buffer)) != -1) {
              bufout.write(buffer, 0, read);
          }

          
          
          
          bufout.close();
          
          zin.closeEntry(); 
          fout.close(); 
        } 
         
      } 
      zin.close(); 
      
      
      Log.d("Unzip", "Unzipping complete. path :  " +_location );
    } catch(Exception e) { 
      Log.e("Decompress", "unzip", e); 
      
      Log.d("Unzip", "Unzipping failed");
    } 
 
  } 
 
  private void _dirChecker(String dir) { 
    File f = new File(_location + dir); 
 
    if(!f.isDirectory()) { 
      f.mkdirs(); 
    } 
  } 


 }

如何使用

 String zipFile = Environment.getExternalStorageDirectory() + "/the_raven.zip"; //your zip file location
    String unzipLocation = Environment.getExternalStorageDirectory() + "/unzippedtestNew/"; // destination folder location
  DecompressFast df= new DecompressFast(zipFile, unzipLocation);
    df.unzip();

权限

 <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
 <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
于 2016-10-19T08:22:16.363 回答
5

根据@zapl 的回答，用进度报告解压：

public interface UnzipFile_Progress
{
    void Progress(int percent, String FileName);
}

// unzip(new File("/sdcard/pictures.zip"), new File("/sdcard"));
public static void UnzipFile(File zipFile, File targetDirectory, UnzipFile_Progress progress) throws IOException,
        FileNotFoundException
{
    long total_len = zipFile.length();
    long total_installed_len = 0;

    ZipInputStream zis = new ZipInputStream(new BufferedInputStream(new FileInputStream(zipFile)));
    try
    {
        ZipEntry ze;
        int count;
        byte[] buffer = new byte[1024];
        while ((ze = zis.getNextEntry()) != null)
        {
            if (progress != null)
            {
                total_installed_len += ze.getCompressedSize();
                String file_name = ze.getName();
                int percent = (int)(total_installed_len * 100 / total_len);
                progress.Progress(percent, file_name);
            }

            File file = new File(targetDirectory, ze.getName());
            File dir = ze.isDirectory() ? file : file.getParentFile();
            if (!dir.isDirectory() && !dir.mkdirs())
                throw new FileNotFoundException("Failed to ensure directory: " + dir.getAbsolutePath());
            if (ze.isDirectory())
                continue;
            FileOutputStream fout = new FileOutputStream(file);
            try
            {
                while ((count = zis.read(buffer)) != -1)
                    fout.write(buffer, 0, count);
            } finally
            {
                fout.close();
            }

            // if time should be restored as well
            long time = ze.getTime();
            if (time > 0)
                file.setLastModified(time);
        }
    } finally
    {
        zis.close();
    }
}
于 2015-01-05T09:54:04.423 回答
3 
public class MainActivity extends Activity {

private String LOG_TAG = MainActivity.class.getSimpleName();

private File zipFile;
private File destination;

private TextView status;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    status = (TextView) findViewById(R.id.main_status);
    status.setGravity(Gravity.CENTER);

    if ( initialize() ) {
        zipFile = new File(destination, "BlueBoxnew.zip");
        try {
            Unzipper.unzip(zipFile, destination);
            status.setText("Extracted to \n"+destination.getAbsolutePath());
        } catch (ZipException e) {
            Log.e(LOG_TAG, e.getMessage());
        } catch (IOException e) {
            Log.e(LOG_TAG, e.getMessage());
        }
    } else {
        status.setText("Unable to initialize sd card.");
    }
}

public boolean initialize() {
    boolean result = false;
     File sdCard = new File(Environment.getExternalStorageDirectory()+"/zip/");
    //File sdCard = Environment.getExternalStorageDirectory();
    if ( sdCard != null ) {
        destination = sdCard;
        if ( !destination.exists() ) {
            if ( destination.mkdir() ) {
                result = true;
            }
        } else {
            result = true;
        }
    }

    return result;
}

 }

->助手类（Unzipper.java）

    import java.io.File;
    import java.io.FileInputStream;
   import java.io.FileOutputStream;
    import java.io.IOException;
       import java.util.zip.ZipEntry;
    import java.util.zip.ZipException;
    import java.util.zip.ZipInputStream;
     import android.util.Log;

   public class Unzipper {

private static String LOG_TAG = Unzipper.class.getSimpleName();

public static void unzip(final File file, final File destination) throws ZipException, IOException {
    new Thread() {
        public void run() {
            long START_TIME = System.currentTimeMillis();
            long FINISH_TIME = 0;
            long ELAPSED_TIME = 0;
            try {
                ZipInputStream zin = new ZipInputStream(new FileInputStream(file));
                String workingDir = destination.getAbsolutePath()+"/";

                byte buffer[] = new byte[4096];
                int bytesRead;
                ZipEntry entry = null;
                while ((entry = zin.getNextEntry()) != null) {
                    if (entry.isDirectory()) {
                        File dir = new File(workingDir, entry.getName());
                        if (!dir.exists()) {
                            dir.mkdir();
                        }
                        Log.i(LOG_TAG, "[DIR] "+entry.getName());
                    } else {
                        FileOutputStream fos = new FileOutputStream(workingDir + entry.getName());
                        while ((bytesRead = zin.read(buffer)) != -1) {
                            fos.write(buffer, 0, bytesRead);
                        }
                        fos.close();
                        Log.i(LOG_TAG, "[FILE] "+entry.getName());
                    }
                }
                zin.close();

                FINISH_TIME = System.currentTimeMillis();
                ELAPSED_TIME = FINISH_TIME - START_TIME;
                Log.i(LOG_TAG, "COMPLETED in "+(ELAPSED_TIME/1000)+" seconds.");
            } catch (Exception e) {
                Log.e(LOG_TAG, "FAILED");
            }
        };
    }.start();
}

   }

->xml 布局（activity_main.xml）：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
   xmlns:tools="http://schemas.android.com/tools"
   android:layout_width="match_parent"
 android:layout_height="match_parent"
 tools:context=".MainActivity" >

<TextView
    android:id="@+id/main_status"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_centerHorizontal="true"
    android:layout_centerVertical="true"
    android:text="@string/hello_world" />

</RelativeLayout>

-> 在 Menifest 文件中的权限：

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
于 2013-09-03T06:16:43.317 回答
2

这是一个 ZipFileIterator（类似于 java Iterator，但用于 zip 文件）：

package ch.epfl.bbp.io;

import java.io.BufferedInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Iterator;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;

public class ZipFileIterator implements Iterator<File> {

    private byte[] buffer = new byte[1024];

    private FileInputStream is;
    private ZipInputStream zis;
    private ZipEntry ze;

    public ZipFileIterator(File file) throws FileNotFoundException {
    is = new FileInputStream(file);
    zis = new ZipInputStream(new BufferedInputStream(is));
    }

    @Override
    public boolean hasNext() {
    try {
        return (ze = zis.getNextEntry()) != null;
    } catch (IOException e) {
        e.printStackTrace();
    }
    return false;
    }

    @Override
    public File next() {
    try {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        int count;

        String filename = ze.getName();
        File tmpFile = File.createTempFile(filename, "tmp");
        tmpFile.deleteOnExit();// TODO make it configurable
        FileOutputStream fout = new FileOutputStream(tmpFile);

        while ((count = zis.read(buffer)) != -1) {
        baos.write(buffer, 0, count);
        byte[] bytes = baos.toByteArray();
        fout.write(bytes);
        baos.reset();
        }
        fout.close();
        zis.closeEntry();

        return tmpFile;

    } catch (Exception e) {
        throw new RuntimeException(e);
    }
    }

    @Override
    public void remove() {
    throw new RuntimeException("not implemented");
    }

    public void close() {
    try {
        zis.close();
        is.close();
    } catch (IOException e) {// nope
    }
    }
}
于 2012-06-04T10:03:47.607 回答
2

我曾经将特定文件从我的 zipfile 解压缩到我的应用程序缓存文件夹中的最小示例。然后我使用不同的方法读取清单文件。

private void unzipUpdateToCache() {
    ZipInputStream zipIs = new ZipInputStream(context.getResources().openRawResource(R.raw.update));
    ZipEntry ze = null;

    try {

        while ((ze = zipIs.getNextEntry()) != null) {
            if (ze.getName().equals("update/manifest.json")) {
                FileOutputStream fout = new FileOutputStream(context.getCacheDir().getAbsolutePath() + "/manifest.json");

                byte[] buffer = new byte[1024];
                int length = 0;

                while ((length = zipIs.read(buffer))>0) {
                    fout.write(buffer, 0, length);
                }
                zipIs .closeEntry();
                fout.close();
            }
        }
        zipIs .close();

    } catch (IOException e) {
        e.printStackTrace();
    }

}
于 2017-03-13T07:27:34.840 回答
2

根据 zapl 的回答，添加try()aroundCloseable会在使用后自动关闭流。

public static void unzip(File zipFile, File targetDirectory) {
    try (FileInputStream fis = new FileInputStream(zipFile)) {
        try (BufferedInputStream bis = new BufferedInputStream(fis)) {
            try (ZipInputStream zis = new ZipInputStream(bis)) {
                ZipEntry ze;
                int count;
                byte[] buffer = new byte[Constant.DefaultBufferSize];
                while ((ze = zis.getNextEntry()) != null) {
                    File file = new File(targetDirectory, ze.getName());
                    File dir = ze.isDirectory() ? file : file.getParentFile();
                    if (!dir.isDirectory() && !dir.mkdirs())
                        throw new FileNotFoundException("Failed to ensure directory: " + dir.getAbsolutePath());
                    if (ze.isDirectory())
                        continue;
                    try (FileOutputStream fout = new FileOutputStream(file)) {
                        while ((count = zis.read(buffer)) != -1)
                            fout.write(buffer, 0, count);
                    }
                }
            }
        }
    } catch (Exception ex) {
        //handle exception
    }
}

从 Jon Skeet 的答案中 使用Constant.DefaultBufferSize( 65536) 从C# .NET 4 Stream.CopyTo获得： https ://stackoverflow.com/a/411605/1876355

我总是只看到使用byte[1024]或byte[4096]缓冲的帖子，从不知道它可以更大，这可以提高性能并且仍然可以正常工作。

这是Stream源代码： https ://referencesource.microsoft.com/#mscorlib/system/io/stream.cs

//We pick a value that is the largest multiple of 4096 that is still smaller than the large object heap threshold (85K).
// The CopyTo/CopyToAsync buffer is short-lived and is likely to be collected at Gen0, and it offers a significant
// improvement in Copy performance.

private const int _DefaultCopyBufferSize = 81920;

但是，为了安全起见，我拨回了65536它也是一个倍数。4096

于 2019-10-31T06:03:53.810 回答
2

我正在处理 Java 的 ZipFile 类无法处理的 zip 文件。Java 8 显然无法处理压缩方法 12（我相信是 bzip2）。在尝试了包括 zip4j 在内的多种方法后（由于另一个问题，这些特定文件也失败了），我在Apache 的 commons-compress上取得了成功，它支持此处提到的其他压缩方法。

请注意，下面的 ZipFile 类不是 java.util.zip 中的类。

它实际上是org.apache.commons.compress.archivers.zip.ZipFile所以要小心导入。

try (ZipFile zipFile = new ZipFile(archiveFile)) {
    Enumeration<ZipArchiveEntry> entries = zipFile.getEntries();
    while (entries.hasMoreElements()) {
        ZipArchiveEntry entry = entries.nextElement();
        File entryDestination = new File(destination, entry.getName());
        if (entry.isDirectory()) {
            entryDestination.mkdirs();
        } else {
            entryDestination.getParentFile().mkdirs();
            try (InputStream in = zipFile.getInputStream(entry); OutputStream out = new FileOutputStream(entryDestination)) {
                IOUtils.copy(in, out);
            }
        }
    }
} catch (IOException ex) {
    log.debug("Error unzipping archive file: " + archiveFile, ex);
}

对于 Gradle：

compile 'org.apache.commons:commons-compress:1.18'
于 2018-08-26T07:15:43.560 回答
1

受密码保护的 Zip 文件

如果你想用密码压缩文件，你可以看看这个库，它可以很容易地用密码压缩文件：

压缩：

ZipArchive zipArchive = new ZipArchive();
zipArchive.zip(targetPath,destinationPath,password);

解压：

ZipArchive zipArchive = new ZipArchive();
zipArchive.unzip(targetPath,destinationPath,password);

拉尔：

RarArchive rarArchive = new RarArchive();
rarArchive.extractArchive(file archive, file destination);

这个库的文档已经足够好了，我只是从那里添加了一些示例。它是完全免费的，专门为 android 编写的。

于 2017-11-07T09:37:52.623 回答
0

这是@arsent 解决方案的更简洁版本：

fun File.unzip(to: File? = null) {
    val destinationDir = to ?: File(parentFile, nameWithoutExtension)
    destinationDir.mkdirs()

    ZipFile(this).use { zipFile ->
        zipFile
            .entries()
            .asSequence()
            .filter { !it.isDirectory }
            .forEach { zipEntry ->
                val currFile = File(destinationDir, zipEntry.name)
                currFile.parentFile?.mkdirs()
                zipFile.getInputStream(zipEntry).use { input ->
                    currFile.outputStream().use { output -> input.copyTo(output) }
                }
            }
    }
}
于 2021-11-17T14:13:18.283 回答