com.renard.ocr.help.OCRLanguageInstallService.java Source code

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Here is the source code for com.renard.ocr.help.OCRLanguageInstallService.java

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/*
 * Copyright (C) 2012,2013 Renard Wellnitz
 *
 * 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.renard.ocr.help;

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 org.apache.commons.compress.archivers.tar.TarArchiveEntry;
import org.apache.commons.compress.archivers.tar.TarArchiveInputStream;
import org.apache.commons.compress.compressors.gzip.GzipCompressorInputStream;

import android.app.DownloadManager;
import android.app.IntentService;
import android.content.Context;
import android.content.Intent;
import android.net.Uri;
import android.os.ParcelFileDescriptor;

import com.renard.util.Util;

public class OCRLanguageInstallService extends IntentService {

    protected static final String ACTION_INSTALL_COMPLETED = "com.renard.ocr.ACTION_OCR_LANGUAGE_INSTALLED";
    protected static final String ACTION_INSTALL_FAILED = "com.renard.ocr.ACTION_INSTALL_FAILED";
    protected static final String EXTRA_OCR_LANGUAGE = "ocr_language";
    protected static final String EXTRA_OCR_LANGUAGE_DISPLAY = "ocr_language_display";
    public static final String EXTRA_STATUS = "status";

    public OCRLanguageInstallService() {
        this(OCRLanguageInstallService.class.getSimpleName());
    }

    public OCRLanguageInstallService(String name) {
        super(name);
    }

    @Override
    protected void onHandleIntent(Intent intent) {
        if (!intent.hasExtra(DownloadManager.EXTRA_DOWNLOAD_ID)) {
            return;
        }
        final long downloadId = intent.getLongExtra(DownloadManager.EXTRA_DOWNLOAD_ID, 0);
        if (downloadId != 0) {

            DownloadManager dm = (DownloadManager) getSystemService(Context.DOWNLOAD_SERVICE);
            ParcelFileDescriptor file;
            try {
                file = dm.openDownloadedFile(downloadId);
                FileInputStream fin = new FileInputStream(file.getFileDescriptor());
                BufferedInputStream in = new BufferedInputStream(fin);
                FileOutputStream out = openFileOutput("tess-lang.tmp", Context.MODE_PRIVATE);
                GzipCompressorInputStream gzIn = new GzipCompressorInputStream(in);
                final byte[] buffer = new byte[2048 * 2];
                int n = 0;
                while (-1 != (n = gzIn.read(buffer))) {
                    out.write(buffer, 0, n);
                }
                out.close();
                gzIn.close();
                FileInputStream fileIn = openFileInput("tess-lang.tmp");
                TarArchiveInputStream tarIn = new TarArchiveInputStream(fileIn);

                TarArchiveEntry entry = tarIn.getNextTarEntry();

                while (entry != null && !(entry.getName().endsWith(".traineddata")
                        && !entry.getName().endsWith("_old.traineddata"))) {
                    entry = tarIn.getNextTarEntry();
                }
                if (entry != null) {
                    File tessDir = Util.getTrainingDataDir(this);
                    final String langName = entry.getName().substring("tesseract-ocr/tessdata/".length());
                    File trainedData = new File(tessDir, langName);
                    FileOutputStream fout = new FileOutputStream(trainedData);
                    int len;
                    while ((len = tarIn.read(buffer)) != -1) {
                        fout.write(buffer, 0, len);
                    }
                    fout.close();
                    String lang = langName.substring(0, langName.length() - ".traineddata".length());
                    notifyReceivers(lang);
                }
                tarIn.close();

            } catch (FileNotFoundException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                String tessDir = Util.getTessDir(this);
                File targetFile = new File(tessDir, OCRLanguageActivity.DOWNLOADED_TRAINING_DATA);
                if (targetFile.exists()) {
                    targetFile.delete();
                }
            }

        }
    }

    private void notifyReceivers(String lang) {
        //notify language activity
        Intent resultIntent = new Intent(ACTION_INSTALL_COMPLETED);
        resultIntent.putExtra(EXTRA_OCR_LANGUAGE, lang);
        resultIntent.putExtra(EXTRA_STATUS, DownloadManager.STATUS_SUCCESSFUL);
        sendBroadcast(resultIntent);
    }
}