unzip Assets - Android App

Android examples for App:Assets

  1. HOME
  2. Android
  3. App
  4. Assets

Description

unzip Assets

Demo Code


import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Enumeration;
import java.util.Vector;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;

import android.content.Context;
import android.util.Log;

public class Main {
  static final String LOGTAG = "";
  static final int BUFSIZE = 5192;
  static final String ZIP_FILTER = "assets";

  static void unzipAssets(Context context) {
    String apkPath = context.getPackageCodePath();
    String mAppRoot = context.getFilesDir().toString();

    try {//w ww.j  av  a  2  s .com
      File zipFile = new File(apkPath);
      long zipLastModified = zipFile.lastModified();
      ZipFile zip = new ZipFile(apkPath);
      Vector<ZipEntry> files = getAssets(zip);
      int zipFilterLength = ZIP_FILTER.length();

      Enumeration<?> entries = files.elements();
      while (entries.hasMoreElements()) {

        ZipEntry entry = (ZipEntry) entries.nextElement();
        String path = entry.getName().substring(zipFilterLength);
        File outputFile = new File(mAppRoot, path);
        outputFile.getParentFile().mkdirs();

        if (outputFile.exists() && entry.getSize() == outputFile.length()
            && zipLastModified < outputFile.lastModified())
          continue;

        FileOutputStream fos = new FileOutputStream(outputFile);
        copyStreams(zip.getInputStream(entry), fos);
        Runtime.getRuntime().exec("chmod 755 " + outputFile.getAbsolutePath());
      }

    } catch (IOException e) {
      Log.e(LOGTAG, "Error: " + e.getMessage());
    }
  }

  public static Vector<ZipEntry> getAssets(ZipFile zip) {
    Vector<ZipEntry> list = new Vector<ZipEntry>();
    Enumeration<?> entries = zip.entries();

    while (entries.hasMoreElements()) {
      ZipEntry entry = (ZipEntry) entries.nextElement();

      if (entry.getName().startsWith(ZIP_FILTER)) {
        list.add(entry);
      }
    }

    return list;
  }

  static void copyStreams(InputStream is, FileOutputStream fos) {
    BufferedOutputStream os = null;

    try {
      byte data[] = new byte[BUFSIZE];
      int count;
      os = new BufferedOutputStream(fos, BUFSIZE);

      while ((count = is.read(data, 0, BUFSIZE)) != -1) {
        os.write(data, 0, count);
      }

      os.flush();

    } catch (IOException e) {
      Log.e(LOGTAG, "Exception while copying: " + e);

    } finally {

      try {

        if (os != null) {
          os.close();
        }

      } catch (IOException e2) {
        Log.e(LOGTAG, "Exception while closing the stream: " + e2);
      }
    }
  }
}

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