Android Open Source - interdroid-vdb Avro Content Provider

• Back to SQLite/database  ↑

From Project

Back to project page interdroid-vdb.

License

The source code is released under:

Copyright (c) 2008-2012 Vrije Universiteit, The Netherlands All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the follo...

Java Source Code

/*
 * Copyright (c) 2008-2012 Vrije Universiteit, The Netherlands All rights
 * reserved.//from  www.  j  a v a 2  s  .c  o m
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of the Vrije Universiteit nor the names of its contributors
 * may be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
package interdroid.vdb.content.avro;

import java.io.IOException;

import org.apache.avro.Schema;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import android.content.Context;
import android.content.pm.ProviderInfo;

import interdroid.vdb.content.DatabaseInitializer;
import interdroid.vdb.content.GenericContentProvider;
import interdroid.vdb.content.metadata.Metadata;
import interdroid.vdb.persistence.api.VdbInitializer;

/**
 * This class implements content providers based on an avro schema.
 *
 * @author nick <palmer@cs.vu.nl>
 *
 */
public class AvroContentProvider extends GenericContentProvider {
  /**
   * Access to logger.
   */
  private static final Logger LOG =
      LoggerFactory.getLogger(AvroContentProvider.class);

  /**
   * The schema for this provider.
   */
  private final Schema mSchema;

  /**
   * The value column name.
   */
  public static final String VALUE_COLUMN_NAME =
      GenericContentProvider.SEPARATOR + "value";
  /**
   * The key column name.
   */
  public static final String KEY_COLUMN_NAME =
      GenericContentProvider.SEPARATOR + "key";
  /**
   * The type column name.
   */
  public static final String TYPE_COLUMN_NAME =
      GenericContentProvider.SEPARATOR + "type";
  /**
   * The ID column name.
   */
  public static final String ID_COLUMN_NAME =
      GenericContentProvider.SEPARATOR + "id";
  /**
   * The infix for array tables.
   */
  public static final String ARRAY_TABLE_INFIX =
      GenericContentProvider.SEPARATOR;
  /**
   * The infix for map tables.
   */
  public static final String MAP_TABLE_INFIX =
      GenericContentProvider.SEPARATOR;
  /**
   * The type name column.
   */
  public static final String TYPE_NAME_COLUMN_NAME =
      TYPE_COLUMN_NAME + GenericContentProvider.SEPARATOR + "name";
  /**
   * The type uri column.
   */
  public static final String TYPE_URI_COLUMN_NAME =
      TYPE_COLUMN_NAME + GenericContentProvider.SEPARATOR + "uri";

  /**
   * Constructs a provider for the given schema.
   * @param schema the schema to act as a content provider for
   */
  public AvroContentProvider(final Schema schema) {
    super(schema.getNamespace(), makeMetadata(schema));
    mSchema = schema;
  }

  /**
   * Constructs the metadata for this schema.
   * @param schema the schema to build metdata for
   * @return the metadata for this schema
   */
  public static Metadata makeMetadata(final Schema schema) {
    return new AvroMetadata(schema);
  }

  /**
   * Constructs a provider for the given schema, parsing it first.
   * @param schema the schema as a string.
   */
  public AvroContentProvider(final String schema) {
    this(Schema.parse(schema));
  }

  /**
   * @return the initializer for the database for this provider
   */
  public final VdbInitializer buildInitializer() {
    LOG.debug("Building initializer: {}", mNamespace);
    return new DatabaseInitializer(mNamespace, mMetadata,
        mSchema.toString());
  }

  @Override
  protected final void onAttach(final Context context,
      final ProviderInfo info) {

    // Make sure we are registered.
    LOG.debug("attachInfo");
    LOG.debug("Registering schema: {}", mSchema.getName());
    try {
      AvroSchemaRegistrationHandler.registerSchema(context, mSchema);
    } catch (IOException e) {
      LOG.error("Unexpected exception registering", e);
    }
    LOG.debug("Schema registered.");
  }
}

Java Source Code List

• Back to SQLite/database  ↑