Android Open Source - tum-campus Feed Manager

• Back to App/campus  ↑

From Project

Back to project page tum-campus.

License

The source code is released under:

GNU General Public License

Java Source Code

?package de.tum.in.tumcampus.models;
/*from   w  w  w .  ja va 2  s  .c  o  m*/
import java.io.File;
import java.util.ArrayList;
import java.util.List;

import de.tum.in.tumcampus.common.Utils;

import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;

/**
 * Feed Manager, handles database stuff, internal imports
 */
public class FeedManager {

  /**
   * Database connection
   */
  private SQLiteDatabase db;

  /**
   * Last insert counter
   */
  public static int lastInserted = 0;

  /**
   * Additional information for exception messages
   */
  public String lastInfo = "";

  /**
   * Constructor, open/create database, create table if necessary
   * 
   * <pre>
   * @param context Context
   * </pre>
   */
  public FeedManager(Context context) {
    db = DatabaseManager.getDb(context);

    // create table if needed
    db.execSQL("CREATE TABLE IF NOT EXISTS feeds ("
        + "id INTEGER PRIMARY KEY AUTOINCREMENT, name VARCHAR, feedUrl VARCHAR)");
  }

  /**
   * Import feeds from internal sd-card directory
   * 
   * @throws Exception
   */
  public void importFromInternal() throws Exception {
    File[] files = new File(Utils.getCacheDir("rss")).listFiles();

    int count = Utils.dbGetTableCount(db, "feeds");

    db.beginTransaction();
    try {
      for (File file : files) {
        String filename = file.getName();
        if (filename.toLowerCase().endsWith(".url")) {
          lastInfo = filename;
          String name = filename.substring(0, filename.length() - 4);
          String url = Utils.getLinkFromUrlFile(file);

          insertUpdateIntoDb(new Feed(name, url));
        }
      }
      db.setTransactionSuccessful();
    } finally {
      db.endTransaction();
    }
    // update last insert counter
    lastInserted += Utils.dbGetTableCount(db, "feeds") - count;
  }

  /**
   * Get all feeds from the database
   * 
   * @return Database cursor (name, feedUrl, _id)
   */
  public Cursor getAllFromDb() {
    return db.rawQuery("SELECT name, feedUrl, id as _id FROM feeds ORDER BY name", null);
  }

  /**
   * Checks if the feeds table is empty
   * 
   * @return true if no feeds are available, else false
   */
  public boolean empty() {
    boolean result = true;
    Cursor c = db.rawQuery("SELECT id FROM feeds LIMIT 1", null);
    if (c.moveToNext()) {
      result = false;
    }
    c.close();
    return result;
  }

  /**
   * Get all Feed IDs from the database
   * 
   * @return List of feed IDs
   */
  public List<Integer> getAllIdsFromDb() {
    List<Integer> list = new ArrayList<Integer>();

    Cursor c = db.rawQuery("SELECT id FROM feeds ORDER BY id", null);
    while (c.moveToNext()) {
      list.add(c.getInt(0));
    }
    c.close();
    return list;
  }

  /**
   * Insert or Update a feed in the database
   * 
   * <pre>
   * @param f Feed object
   * @return Feed ID
   * @throws Exception
   * </pre>
   */
  public int insertUpdateIntoDb(Feed f) throws Exception {
    Utils.log(f.toString());

    f.name = f.name.trim();
    f.feedUrl = f.feedUrl.trim();

    if (f.name.length() == 0) {
      throw new Exception("Invalid name.");
    }
    if (f.feedUrl.length() == 0) {
      throw new Exception("Invalid feedUrl.");
    }

    Cursor c = db.rawQuery("SELECT id FROM feeds WHERE name = ?", new String[] { f.name });

    if (c.moveToNext()) {
      db.execSQL("UPDATE feeds SET name=?, feedUrl=? WHERE id=?",
          new String[] { f.name, f.feedUrl, c.getString(0) });
      return c.getInt(0);
    }
    db.execSQL("INSERT INTO feeds (name, feedUrl) VALUES (?, ?)", new String[] { f.name, f.feedUrl });

    c = db.rawQuery("SELECT last_insert_rowid()", null);
    c.moveToNext();
    return c.getInt(0);
  }

  /**
   * Delete feed from database
   * 
   * <pre>
   * @param id Feed ID
   * </pre>
   */
  public void deleteFromDb(int id) {
    db.execSQL("DELETE FROM feeds WHERE id = ?", new String[] { String.valueOf(id) });
  }
}

Java Source Code List

• Back to App/campus  ↑