Implementation of two versions of the utilities to decompress zip archives (ZipInputStream & ZipFile).

ZipFileUtils.java

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

/**
 * 
 * The class is responsible for unpacking ZIP file. The implementation is based on {@link ZipFile}.
 * 
 * @author johnkil
 * 
 */
public class ZipFileUtils {
    private static final String LOG_TAG = ZipFileUtils.class.getSimpleName();

    private static final int BUFFER_SIZE = 8 * 1024;

    /**
     * Unpack ZIP archive to specified directory.
     * 
     * @param srcFile - ZIP file
     * @param outputDir - destination directory
     * @return true in case of success, otherwise - false.
     */
    public static boolean unzipFile(File srcFile, File outputDir) {
        Log.d(LOG_TAG, "Unpacking %s to %s", srcFile, outputDir);
        boolean result = false;
        ZipFile zipFile = null;
        try {
            zipFile = new ZipFile(srcFile);
            Enumeration<? extends ZipEntry> entries = zipFile.entries();
            while (entries.hasMoreElements()) {
                ZipEntry zipEntry = (ZipEntry) entries.nextElement();
                unzipEntry(zipEntry, zipFile, outputDir);
            }
            result = true;
        } catch (IOException e) {
            Log.e(LOG_TAG, e);
        } finally {
            if (zipFile != null) {
                try {
                    zipFile.close();
                } catch (IOException e) {
                    Log.e(LOG_TAG, "Unable to close zip-archive", e);
                }
            }
        }
        return result;
    }

    /**
     * Unzip entry from ZIP file into outputDir.
     * 
     * @param zipEntry Specify entry from ZIP file
     * @param zipFile ZIP file
     * @param outputDir Destination directory
     * @throws IOException
     */
    private static void unzipEntry(ZipEntry zipEntry, ZipFile zipFile, File outputDir) throws IOException {
        File file = new File(outputDir, zipEntry.getName());
        if (zipEntry.isDirectory()) {
            // unzip directory
            if (!file.exists()) {
                if (file.mkdirs()) {
                    Log.d(LOG_TAG, "%s directory created", file);
                } else {
                    throw new IOException(String.format("%s failure to create directory", file));
                }
            } else {
                Log.w(LOG_TAG, "%s directory is already created", file);
            }
        } else {
            // unzip file
            BufferedOutputStream out = null;
            BufferedInputStream in = null;
            try {
                out = new BufferedOutputStream(new FileOutputStream(file), BUFFER_SIZE);
                in = new BufferedInputStream(zipFile.getInputStream(zipEntry), BUFFER_SIZE);
                FileUtils.copyFile(in, out);
                out.flush();
                Log.d(LOG_TAG, "%s file created", file);
            } finally {
                if (in != null) {
                    try {
                        in.close();
                    } catch (IOException e) {
                        Log.e(LOG_TAG, e);
                    }
                }
                if (out != null) {
                    try {
                        out.close();
                    } catch (IOException e) {
                        Log.e(LOG_TAG, e);
                    }
                }
            }
        }
    }

}

ZipUtils.java

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;

/**
 * The class is responsible for unpacking ZIP file. The implementation is based on {@link ZipInputStream}.
 * 
 * @author johnkil
 * 
 */
public class ZipUtils {
    private static final String LOG_TAG = ZipUtils.class.getSimpleName();

    private static final int BUFFER_SIZE = 8 * 1024;

    /**
     * Invisible constructor.
     */
    private ZipUtils() {
    }

    /**
     * UNZIP file into outputDir.
     * 
     * @param zipFile The source ZIP file
     * @param outputDir Destination directory
     * @return true if successful, else false
     */
    public static boolean unzip(File zipFile, File outputDir) {
        Log.d(LOG_TAG, "Unpacking %s to %s", zipFile, outputDir);
        try {
            return unzip(new FileInputStream(zipFile), outputDir);
        } catch (FileNotFoundException e) {
            Log.e(LOG_TAG, "%s file does not exist", zipFile);
        }
        return false;
    }

    /**
     * UNZIP InputStream into outputDir.
     * 
     * @param in The source zipped {@link InputStream}
     * @param outputDir Destination directory
     * @return true if successful, else false
     */
    public static boolean unzip(InputStream in, File outputDir) {
        Log.v(LOG_TAG, "unzip() called: outputDir=[%s]", outputDir.getPath());
        ZipInputStream zipInputStream = new ZipInputStream(new BufferedInputStream(in, BUFFER_SIZE));
        try {
            if (outputDir.exists() && !outputDir.isDirectory()) {
                Log.e(LOG_TAG, "outputDir [%s] is not the directory", outputDir.getPath());
                return false;
            } else if (!outputDir.exists() && !outputDir.mkdirs()) {
                Log.e(LOG_TAG, "fail of creating outputDir [%s]", outputDir.getPath());
                return false;
            }
            ZipEntry zipEntry = null;
            while ((zipEntry = zipInputStream.getNextEntry()) != null) {
                unzipEntry(zipEntry, zipInputStream, outputDir);
            }
            return true;
        } catch (IOException e) {
            Log.w(LOG_TAG, e);
        } finally {
            try {
                zipInputStream.close();
            } catch (IOException e) {
                Log.w(LOG_TAG, e);
            }
        }
        return false;
    }

    /**
     * UNZIP entry from ZIP file into outputDir.
     * 
     * @param zipEntry Specify entry from ZIP file
     * @param zipInputStream The source {@link ZipInputStream}
     * @param outputDir Destination directory
     * @throws IOException
     */
    private static void unzipEntry(ZipEntry zipEntry, ZipInputStream zipInputStream, File outputDir) throws IOException {
        Log.v(LOG_TAG, "unzipEntry() called: zipEntry=[%s], outputDir=[%s]", zipEntry, outputDir);
        File file = new File(outputDir, zipEntry.getName());
        if (zipEntry.isDirectory()) {
            // unzip directory
            if (!file.exists()) {
                if (file.mkdirs()) {
                    Log.d(LOG_TAG, "%s directory created", file);
                } else {
                    throw new IOException(String.format("%s failure to create directory", file));
                }
            } else {
                Log.w(LOG_TAG, "%s directory is already created", file);
            }
        } else {
            // unzip file
            BufferedOutputStream out = null;
            try {
                out = new BufferedOutputStream(new FileOutputStream(file), BUFFER_SIZE);
                FileUtils.copyFile(zipInputStream, out);
                out.flush();
                Log.d(LOG_TAG, "%s file created", file);
            } finally {
                if (out != null) {
                    try {
                        out.close();
                    } catch (IOException e) {
                        Log.e(LOG_TAG, e);
                    }
                }
                try {
                    zipInputStream.closeEntry();
                } catch (IOException e) {
                    Log.w(LOG_TAG, e);
                }
            }
        }
    }

}