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License

The source code is released under:

GNU Lesser General Public License

Java Source Code

package org.kered.contactlensfinder;
//from   w  w  w .ja  v a  2s .  c o  m
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.sql.Connection;
import java.sql.Driver;
import java.sql.DriverManager;
import java.sql.SQLException;

import org.kered.dko.Context.Undoer;
import org.kered.dko.datasource.SingleConnectionDataSource;

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

public class DB {
  
    private static final String DB_FILENAME = "myapp.db";
    private static final String ASSETS_INIT_DB_FILENAME = "init.db";
    private static boolean initted = false;
    
  /**
   * Call once per application run.  Multiple calls are OK / ignored.
   * Recommend in the onCreate() of you main activity.
   * Copies an initial sqlite3 database out of you assets folder
   * into you data folder, then sets up a default DataSource.
   * @param context
   */
  public static void getReady(Context context) {
    try {
      getReadyThrow(context);
    } catch (Exception e) {
      throw new RuntimeException(e);
    }
  }

    public static void getReadyThrow(final Context context) throws IOException, SQLException {
      if (initted) return;
    initDriver();
    boolean needToInitDatabase = !new File(getDatabaseFilename(context)).exists();
    Log.v(TAG, needToInitDatabase ? "i need to init our db..." : "i do not need to init our db");
    if (needToInitDatabase) {
      initOnDeviceDatabase(context);
      Log.v(TAG, "...db initted! ");
    }
    setDefaultDataSource(context);
    initted = true;
  }

  private static void initOnDeviceDatabase(final Context context) throws IOException {
    // copies from assets/ to /data/data/.../
    InputStream in = context.getAssets().open(ASSETS_INIT_DB_FILENAME);
    OutputStream out = new FileOutputStream(getDatabaseFilename(context));
    byte[] buffer = new byte[1024];
    for (int len; (len = in.read(buffer)) != -1; ) {
      out.write(buffer, 0, len);
    }
    out.flush();
    out.close();
    in.close();
  }

    private static void initDriver() {
      // make sure the SQLDroid driver is loaded
    try {
      final Driver d = (Driver) Class.forName("org.sqldroid.SQLDroidDriver").newInstance();
    } catch (final Exception e) {
      throw new RuntimeException(e);
    }
    }

    private static void setDefaultDataSource(Context context) {
    try {
      
      // SQLDroid connections are expensive to create, so use a DKO helper
      // class that acts as a really simple connection pool.
      Connection conn = DriverManager.getConnection(getDatabaseURL(context));
      SingleConnectionDataSource ds = new SingleConnectionDataSource(conn);

      // setAutoUndo(false) is important here, otherwise this contextual setting
      // will revert itself once the Undoer object is GCed.
      Undoer undoer = org.kered.dko.Context.getVMContext().setDataSource(ds);
      undoer.setAutoUndo(false);

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

  private static String getDatabaseURL(Context context) {
    return "jdbc:sqldroid:"+ getDatabaseFilename(context);
  }

  private static String getDatabaseFilename(Context context) {
    return context.getApplicationInfo().dataDir +"/"+ DB_FILENAME;
  }

  private static final String TAG = "DB";

}

Java Source Code List

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