com.googlecode.android_scripting.ZipExtractorTask.java Source code

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Here is the source code for com.googlecode.android_scripting.ZipExtractorTask.java

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/*
 * Copyright (C) 2010 Google Inc.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package com.googlecode.android_scripting;

import android.app.AlertDialog;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.DialogInterface.OnCancelListener;
import android.os.AsyncTask;

import com.googlecode.android_scripting.exception.Sl4aException;
import com.googlecode.android_scripting.future.FutureResult;

import java.io.BufferedInputStream;
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.Enumeration;
import java.util.zip.GZIPInputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;

import org.apache.http.util.ByteArrayBuffer;
import org.xml.sax.InputSource;

/**
 * AsyncTask for extracting ZIP files.
 * 
 * @author Damon Kohler (damonkohler@gmail.com)
 * @author Alexey Reznichenko (alexey.reznichenko@gmail.com)
 */
public class ZipExtractorTask extends AsyncTask<Void, Integer, Long> {

    private static enum Replace {
        YES, NO, YESTOALL, SKIPALL
    }

    private final File mInput;
    private final File mOutput;
    private final ProgressDialog mDialog;
    private Throwable mException;
    private int mProgress = 0;
    private final Context mContext;
    private boolean mReplaceAll;

    private final class ProgressReportingOutputStream extends FileOutputStream {
        private ProgressReportingOutputStream(File f) throws FileNotFoundException {
            super(f);
        }

        @Override
        public void write(byte[] buffer, int offset, int count) throws IOException {
            super.write(buffer, offset, count);
            mProgress += count;
            publishProgress(mProgress);
        }
    }

    public ZipExtractorTask(String in, String out, Context context, boolean replaceAll) throws Sl4aException {
        super();
        mInput = new File(in);
        mOutput = new File(out);
        if (!mOutput.exists()) {
            if (!mOutput.mkdirs()) {
                throw new Sl4aException("Failed to make directories: " + mOutput.getAbsolutePath());
            }
        }
        if (context != null) {
            mDialog = new ProgressDialog(context);
        } else {
            mDialog = null;
        }

        mContext = context;
        mReplaceAll = replaceAll;

    }

    @Override
    protected void onPreExecute() {
        Log.v("Extracting " + mInput.getAbsolutePath() + " to " + mOutput.getAbsolutePath());
        if (mDialog != null) {
            mDialog.setTitle("Extracting");
            mDialog.setMessage(mInput.getName());
            mDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
            mDialog.setOnCancelListener(new OnCancelListener() {
                @Override
                public void onCancel(DialogInterface dialog) {
                    cancel(true);
                }
            });
            mDialog.show();
        }
    }

    @Override
    protected Long doInBackground(Void... params) {
        try {
            return unzip();
        } catch (Exception e) {
            if (mInput.exists()) {
                // Clean up bad zip file.
                mInput.delete();
            }
            mException = e;
            return null;
        }
    }

    @Override
    protected void onProgressUpdate(Integer... progress) {
        if (mDialog == null) {
            return;
        }
        if (progress.length > 1) {
            int max = progress[1];
            mDialog.setMax(max);
        } else {
            mDialog.setProgress(progress[0].intValue());
        }
    }

    @Override
    protected void onPostExecute(Long result) {
        if (mDialog != null && mDialog.isShowing()) {
            mDialog.dismiss();
        }
        if (isCancelled()) {
            return;
        }
        if (mException != null) {
            Log.e("Zip extraction failed.", mException);
        }
    }

    @Override
    protected void onCancelled() {
        if (mDialog != null) {
            mDialog.setTitle("Extraction cancelled.");
        }
    }

    private long unzip() throws Exception {
        long extractedSize = 0l;
        Enumeration<? extends ZipEntry> entries;
        if (mInput.isFile() && mInput.getName().contains(".gz")) {
            InputStream stream = new FileInputStream(mInput);
            GZIPInputStream gzipStream = new GZIPInputStream(stream);
            InputSource is = new InputSource(gzipStream);
            InputStream input = new BufferedInputStream(is.getByteStream());
            File destination = new File(mOutput, "php");
            ByteArrayBuffer baf = new ByteArrayBuffer(255000);
            int current = 0;
            while ((current = input.read()) != -1) {
                baf.append((byte) current);
            }

            FileOutputStream output = new FileOutputStream(destination);
            output.write(baf.toByteArray());
            output.close();
            Log.d("written!");
            return baf.toByteArray().length;
        }
        ZipFile zip = new ZipFile(mInput);
        long uncompressedSize = getOriginalSize(zip);

        publishProgress(0, (int) uncompressedSize);

        entries = zip.entries();

        try {
            while (entries.hasMoreElements()) {
                ZipEntry entry = entries.nextElement();
                if (entry.isDirectory()) {
                    // Not all zip files actually include separate directory entries.
                    // We'll just ignore them
                    // and create them as necessary for each actual entry.
                    continue;
                }
                File destination = new File(mOutput, entry.getName());
                if (!destination.getParentFile().exists()) {
                    destination.getParentFile().mkdirs();
                }
                if (destination.exists() && mContext != null && !mReplaceAll) {
                    Replace answer = showDialog(entry.getName());
                    switch (answer) {
                    case YES:
                        break;
                    case NO:
                        continue;
                    case YESTOALL:
                        mReplaceAll = true;
                        break;
                    default:
                        return extractedSize;
                    }
                }
                ProgressReportingOutputStream outStream = new ProgressReportingOutputStream(destination);
                extractedSize += IoUtils.copy(zip.getInputStream(entry), outStream);
                outStream.close();
            }
        } finally {
            try {
                zip.close();
            } catch (Exception e) {
                // swallow this exception, we are only interested in the original one
            }
        }
        Log.v("Extraction is complete.");
        return extractedSize;
    }

    private long getOriginalSize(ZipFile file) {
        Enumeration<? extends ZipEntry> entries = file.entries();
        long originalSize = 0l;
        while (entries.hasMoreElements()) {
            ZipEntry entry = entries.nextElement();
            if (entry.getSize() >= 0) {
                originalSize += entry.getSize();
            }
        }
        return originalSize;
    }

    private Replace showDialog(final String name) {
        final FutureResult<Replace> mResult = new FutureResult<Replace>();

        MainThread.run(mContext, new Runnable() {
            @Override
            public void run() {
                AlertDialog.Builder builder = new AlertDialog.Builder(mContext);
                builder.setTitle(String.format("Script \"%s\" already exist.", name));
                builder.setMessage(String.format("Do you want to replace script \"%s\" ?", name));

                DialogInterface.OnClickListener buttonListener = new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        Replace result = Replace.SKIPALL;
                        switch (which) {
                        case DialogInterface.BUTTON_POSITIVE:
                            result = Replace.YES;
                            break;
                        case DialogInterface.BUTTON_NEGATIVE:
                            result = Replace.NO;
                            break;
                        case DialogInterface.BUTTON_NEUTRAL:
                            result = Replace.YESTOALL;
                            break;
                        }
                        mResult.set(result);
                        dialog.dismiss();
                    }
                };
                builder.setNegativeButton("Skip", buttonListener);
                builder.setPositiveButton("Replace", buttonListener);
                builder.setNeutralButton("Replace All", buttonListener);

                builder.setOnCancelListener(new DialogInterface.OnCancelListener() {
                    @Override
                    public void onCancel(DialogInterface dialog) {
                        mResult.set(Replace.SKIPALL);
                        dialog.dismiss();
                    }
                });
                builder.show();
            }
        });

        try {
            return mResult.get();
        } catch (InterruptedException e) {
            Log.e(e);
        }
        return null;
    }
}