src/com/android/settings/search/DatabaseResultLoader.java - platform/packages/apps/Settings - Git at Google

 /*
  * Copyright (C) 2017 The Android Open Source Project
  *
  * 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.android.settings.search;

 import static com.android.settings.search.IndexDatabaseHelper.IndexColumns;
 import static com.android.settings.search.IndexDatabaseHelper.Tables.TABLE_PREFS_INDEX;

 import android.content.Context;
 import android.database.Cursor;
 import android.database.sqlite.SQLiteDatabase;
 import android.support.annotation.VisibleForTesting;

 import com.android.settings.dashboard.SiteMapManager;
 import com.android.settings.utils.AsyncLoader;

 import java.util.HashSet;
 import java.util.Set;

 /**
  * AsyncTask to retrieve Settings, First party app and any intent based results.
  */
 public class DatabaseResultLoader extends AsyncLoader<Set<? extends SearchResult>> {
     private static final String LOG = "DatabaseResultLoader";

     /* These indices are used to match the columns of the this loader's SELECT statement.
      These are not necessarily the same order nor similar coverage as the schema defined in
      IndexDatabaseHelper */
     static final int COLUMN_INDEX_ID = 0;
     static final int COLUMN_INDEX_TITLE = 1;
     static final int COLUMN_INDEX_SUMMARY_ON = 2;
     static final int COLUMN_INDEX_SUMMARY_OFF = 3;
     static final int COLUMN_INDEX_CLASS_NAME = 4;
     static final int COLUMN_INDEX_SCREEN_TITLE = 5;
     static final int COLUMN_INDEX_ICON = 6;
     static final int COLUMN_INDEX_INTENT_ACTION = 7;
     static final int COLUMN_INDEX_INTENT_ACTION_TARGET_PACKAGE = 8;
     static final int COLUMN_INDEX_INTENT_ACTION_TARGET_CLASS = 9;
     static final int COLUMN_INDEX_KEY = 10;
     static final int COLUMN_INDEX_PAYLOAD_TYPE = 11;
     static final int COLUMN_INDEX_PAYLOAD = 12;

     public static final String[] SELECT_COLUMNS = {
             IndexColumns.DOCID,
             IndexColumns.DATA_TITLE,
             IndexColumns.DATA_SUMMARY_ON,
             IndexColumns.DATA_SUMMARY_OFF,
             IndexColumns.CLASS_NAME,
             IndexColumns.SCREEN_TITLE,
             IndexColumns.ICON,
             IndexColumns.INTENT_ACTION,
             IndexColumns.INTENT_TARGET_PACKAGE,
             IndexColumns.INTENT_TARGET_CLASS,
             IndexColumns.DATA_KEY_REF,
             IndexColumns.PAYLOAD_TYPE,
             IndexColumns.PAYLOAD
     };

     public static final String[] MATCH_COLUMNS_PRIMARY = {
             IndexColumns.DATA_TITLE,
             IndexColumns.DATA_TITLE_NORMALIZED,
     };

     public static final String[] MATCH_COLUMNS_SECONDARY = {
             IndexColumns.DATA_SUMMARY_ON,
             IndexColumns.DATA_SUMMARY_ON_NORMALIZED,
             IndexColumns.DATA_SUMMARY_OFF,
             IndexColumns.DATA_SUMMARY_OFF_NORMALIZED,
     };

     public static final String[] MATCH_COLUMNS_TERTIARY = {
             IndexColumns.DATA_KEYWORDS,
             IndexColumns.DATA_ENTRIES
     };

     /**
      * Base ranks defines the best possible rank based on what the query matches.
      * If the query matches the prefix of the first word in the title, the best rank it can be is 1
      * If the query matches the prefix of the other words in the title, the best rank it can be is 3
      * If the query only matches the summary, the best rank it can be is 7
      * If the query only matches keywords or entries, the best rank it can be is 9
      *
      */
     public static final int[] BASE_RANKS = {1, 3, 7, 9};

     @VisibleForTesting
     final String mQueryText;
     private final Context mContext;
     private final CursorToSearchResultConverter mConverter;
     private final SiteMapManager mSiteMapManager;

     public DatabaseResultLoader(Context context, String queryText, SiteMapManager mapManager) {
         super(context);
         mSiteMapManager = mapManager;
         mContext = context;
         mQueryText = queryText;
         mConverter = new CursorToSearchResultConverter(context);
     }

     @Override
     protected void onDiscardResult(Set<? extends SearchResult> result) {
         // TODO Search
     }

     @Override
     public Set<? extends SearchResult> loadInBackground() {
         if (mQueryText == null || mQueryText.isEmpty()) {
             return null;
         }

         final Set<SearchResult> results = new HashSet<>();

         results.addAll(firstWordQuery(MATCH_COLUMNS_PRIMARY, BASE_RANKS[0]));
         results.addAll(secondaryWordQuery(MATCH_COLUMNS_PRIMARY, BASE_RANKS[1]));
         results.addAll(anyWordQuery(MATCH_COLUMNS_SECONDARY, BASE_RANKS[2]));
         results.addAll(anyWordQuery(MATCH_COLUMNS_TERTIARY, BASE_RANKS[3]));
         return results;
     }

     @Override
     protected boolean onCancelLoad() {
         // TODO
         return super.onCancelLoad();
     }

     /**
      * Creates and executes the query which matches prefixes of the first word of the given columns.
      *
      * @param matchColumns The columns to match on
      * @param baseRank The highest rank achievable by these results
      * @return A set of the matching results.
      */
     private Set<SearchResult> firstWordQuery(String[] matchColumns, int baseRank) {
         final String whereClause = buildSingleWordWhereClause(matchColumns);
         final String query = mQueryText + "%";
         final String[] selection = buildSingleWordSelection(query, matchColumns.length);

         return query(whereClause, selection, baseRank);
     }

     /**
      * Creates and executes the query which matches prefixes of the non-first words of the
      * given columns.
      *
      * @param matchColumns The columns to match on
      * @param baseRank The highest rank achievable by these results
      * @return A set of the matching results.
      */
     private Set<SearchResult> secondaryWordQuery(String[] matchColumns, int baseRank) {
         final String whereClause = buildSingleWordWhereClause(matchColumns);
         final String query = "% " + mQueryText + "%";
         final String[] selection = buildSingleWordSelection(query, matchColumns.length);

         return query(whereClause, selection, baseRank);
     }

     /**
      * Creates and executes the query which matches prefixes of the any word of the given columns.
      *
      * @param matchColumns The columns to match on
      * @param baseRank The highest rank achievable by these results
      * @return A set of the matching results.
      */
     private Set<SearchResult> anyWordQuery(String[] matchColumns, int baseRank) {
         final String whereClause = buildTwoWordWhereClause(matchColumns);
         final String[] selection = buildAnyWordSelection(matchColumns.length * 2);

         return query(whereClause, selection, baseRank);
     }

     /**
      * Generic method used by all of the query methods above to execute a query.
      *
      * @param whereClause Where clause for the SQL query which uses bindings.
      * @param selection List of the transformed query to match each bind in the whereClause
      * @param baseRank The highest rank achievable by these results.
      * @return A set of the matching results.
      */
     private Set<SearchResult> query(String whereClause, String[] selection, int baseRank) {
         final SQLiteDatabase database =
                 IndexDatabaseHelper.getInstance(mContext).getReadableDatabase();
         try (Cursor resultCursor = database.query(TABLE_PREFS_INDEX, SELECT_COLUMNS, whereClause,
                 selection, null, null, null)) {
             return mConverter.convertCursor(mSiteMapManager, resultCursor, baseRank);
         }
     }

     /**
      * Builds the SQLite WHERE clause that matches all matchColumns for a single query.
      *
      * @param matchColumns List of columns that will be used for matching.
      * @return The constructed WHERE clause.
      */
     private static String buildSingleWordWhereClause(String[] matchColumns) {
         StringBuilder sb = new StringBuilder(" (");
         final int count = matchColumns.length;
         for (int n = 0; n < count; n++) {
             sb.append(matchColumns[n]);
             sb.append(" like ? ");
             if (n < count - 1) {
                 sb.append(" OR ");
             }
         }
         sb.append(") AND enabled = 1");
         return sb.toString();
     }

     /**
      * Builds the SQLite WHERE clause that matches all matchColumns to two different queries.
      *
      * @param matchColumns List of columns that will be used for matching.
      * @return The constructed WHERE clause.
      */
     private static String buildTwoWordWhereClause(String[] matchColumns) {
         StringBuilder sb = new StringBuilder(" (");
         final int count = matchColumns.length;
         for (int n = 0; n < count; n++) {
             sb.append(matchColumns[n]);
             sb.append(" like ? OR ");
             sb.append(matchColumns[n]);
             sb.append(" like ?");
             if (n < count - 1) {
                 sb.append(" OR ");
             }
         }
         sb.append(") AND enabled = 1");
         return sb.toString();
     }

     /**
      * Fills out the selection array to match the query as the prefix of a single word.
      *
      * @param size is the number of columns to be matched.
      */
     private String[] buildSingleWordSelection(String query, int size) {
         String[] selection = new String[size];

         for(int i = 0; i < size; i ++) {
             selection[i] = query;
         }
         return selection;
     }

     /**
      * Fills out the selection array to match the query as the prefix of a word.
      *
      * @param size is twice the number of columns to be matched. The first match is for the prefix
      *             of the first word in the column. The second match is for any subsequent word
      *             prefix match.
      */
     private String[] buildAnyWordSelection(int size) {
         String[] selection = new String[size];
         final String query = mQueryText + "%";
         final String subStringQuery = "% " + mQueryText + "%";

         for(int i = 0; i < (size - 1); i += 2) {
             selection[i] = query;
             selection[i + 1] = subStringQuery;
         }
         return selection;
     }
 }
	/*
	* Copyright (C) 2017 The Android Open Source Project
	*
	* 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.android.settings.search;

	import static com.android.settings.search.IndexDatabaseHelper.IndexColumns;
	import static com.android.settings.search.IndexDatabaseHelper.Tables.TABLE_PREFS_INDEX;

	import android.content.Context;
	import android.database.Cursor;
	import android.database.sqlite.SQLiteDatabase;
	import android.support.annotation.VisibleForTesting;

	import com.android.settings.dashboard.SiteMapManager;
	import com.android.settings.utils.AsyncLoader;

	import java.util.HashSet;
	import java.util.Set;

	/**
	* AsyncTask to retrieve Settings, First party app and any intent based results.
	*/
	public class DatabaseResultLoader extends AsyncLoader<Set<? extends SearchResult>> {
	private static final String LOG = "DatabaseResultLoader";

	/* These indices are used to match the columns of the this loader's SELECT statement.
	These are not necessarily the same order nor similar coverage as the schema defined in
	IndexDatabaseHelper */
	static final int COLUMN_INDEX_ID = 0;
	static final int COLUMN_INDEX_TITLE = 1;
	static final int COLUMN_INDEX_SUMMARY_ON = 2;
	static final int COLUMN_INDEX_SUMMARY_OFF = 3;
	static final int COLUMN_INDEX_CLASS_NAME = 4;
	static final int COLUMN_INDEX_SCREEN_TITLE = 5;
	static final int COLUMN_INDEX_ICON = 6;
	static final int COLUMN_INDEX_INTENT_ACTION = 7;
	static final int COLUMN_INDEX_INTENT_ACTION_TARGET_PACKAGE = 8;
	static final int COLUMN_INDEX_INTENT_ACTION_TARGET_CLASS = 9;
	static final int COLUMN_INDEX_KEY = 10;
	static final int COLUMN_INDEX_PAYLOAD_TYPE = 11;
	static final int COLUMN_INDEX_PAYLOAD = 12;

	public static final String[] SELECT_COLUMNS = {
	IndexColumns.DOCID,
	IndexColumns.DATA_TITLE,
	IndexColumns.DATA_SUMMARY_ON,
	IndexColumns.DATA_SUMMARY_OFF,
	IndexColumns.CLASS_NAME,
	IndexColumns.SCREEN_TITLE,
	IndexColumns.ICON,
	IndexColumns.INTENT_ACTION,
	IndexColumns.INTENT_TARGET_PACKAGE,
	IndexColumns.INTENT_TARGET_CLASS,
	IndexColumns.DATA_KEY_REF,
	IndexColumns.PAYLOAD_TYPE,
	IndexColumns.PAYLOAD
	};

	public static final String[] MATCH_COLUMNS_PRIMARY = {
	IndexColumns.DATA_TITLE,
	IndexColumns.DATA_TITLE_NORMALIZED,
	};

	public static final String[] MATCH_COLUMNS_SECONDARY = {
	IndexColumns.DATA_SUMMARY_ON,
	IndexColumns.DATA_SUMMARY_ON_NORMALIZED,
	IndexColumns.DATA_SUMMARY_OFF,
	IndexColumns.DATA_SUMMARY_OFF_NORMALIZED,
	};

	public static final String[] MATCH_COLUMNS_TERTIARY = {
	IndexColumns.DATA_KEYWORDS,
	IndexColumns.DATA_ENTRIES
	};

	/**
	* Base ranks defines the best possible rank based on what the query matches.
	* If the query matches the prefix of the first word in the title, the best rank it can be is 1
	* If the query matches the prefix of the other words in the title, the best rank it can be is 3
	* If the query only matches the summary, the best rank it can be is 7
	* If the query only matches keywords or entries, the best rank it can be is 9
	*
	*/
	public static final int[] BASE_RANKS = {1, 3, 7, 9};

	@VisibleForTesting
	final String mQueryText;
	private final Context mContext;
	private final CursorToSearchResultConverter mConverter;
	private final SiteMapManager mSiteMapManager;

	public DatabaseResultLoader(Context context, String queryText, SiteMapManager mapManager) {
	super(context);
	mSiteMapManager = mapManager;
	mContext = context;
	mQueryText = queryText;
	mConverter = new CursorToSearchResultConverter(context);
	}

	@Override
	protected void onDiscardResult(Set<? extends SearchResult> result) {
	// TODO Search
	}

	@Override
	public Set<? extends SearchResult> loadInBackground() {
	if (mQueryText == null \|\| mQueryText.isEmpty()) {
	return null;
	}

	final Set<SearchResult> results = new HashSet<>();

	results.addAll(firstWordQuery(MATCH_COLUMNS_PRIMARY, BASE_RANKS[0]));
	results.addAll(secondaryWordQuery(MATCH_COLUMNS_PRIMARY, BASE_RANKS[1]));
	results.addAll(anyWordQuery(MATCH_COLUMNS_SECONDARY, BASE_RANKS[2]));
	results.addAll(anyWordQuery(MATCH_COLUMNS_TERTIARY, BASE_RANKS[3]));
	return results;
	}

	@Override
	protected boolean onCancelLoad() {
	// TODO
	return super.onCancelLoad();
	}

	/**
	* Creates and executes the query which matches prefixes of the first word of the given columns.
	*
	* @param matchColumns The columns to match on
	* @param baseRank The highest rank achievable by these results
	* @return A set of the matching results.
	*/
	private Set<SearchResult> firstWordQuery(String[] matchColumns, int baseRank) {
	final String whereClause = buildSingleWordWhereClause(matchColumns);
	final String query = mQueryText + "%";
	final String[] selection = buildSingleWordSelection(query, matchColumns.length);

	return query(whereClause, selection, baseRank);
	}

	/**
	* Creates and executes the query which matches prefixes of the non-first words of the
	* given columns.
	*
	* @param matchColumns The columns to match on
	* @param baseRank The highest rank achievable by these results
	* @return A set of the matching results.
	*/
	private Set<SearchResult> secondaryWordQuery(String[] matchColumns, int baseRank) {
	final String whereClause = buildSingleWordWhereClause(matchColumns);
	final String query = "% " + mQueryText + "%";
	final String[] selection = buildSingleWordSelection(query, matchColumns.length);

	return query(whereClause, selection, baseRank);
	}

	/**
	* Creates and executes the query which matches prefixes of the any word of the given columns.
	*
	* @param matchColumns The columns to match on
	* @param baseRank The highest rank achievable by these results
	* @return A set of the matching results.
	*/
	private Set<SearchResult> anyWordQuery(String[] matchColumns, int baseRank) {
	final String whereClause = buildTwoWordWhereClause(matchColumns);
	final String[] selection = buildAnyWordSelection(matchColumns.length * 2);

	return query(whereClause, selection, baseRank);
	}

	/**
	* Generic method used by all of the query methods above to execute a query.
	*
	* @param whereClause Where clause for the SQL query which uses bindings.
	* @param selection List of the transformed query to match each bind in the whereClause
	* @param baseRank The highest rank achievable by these results.
	* @return A set of the matching results.
	*/
	private Set<SearchResult> query(String whereClause, String[] selection, int baseRank) {
	final SQLiteDatabase database =
	IndexDatabaseHelper.getInstance(mContext).getReadableDatabase();
	try (Cursor resultCursor = database.query(TABLE_PREFS_INDEX, SELECT_COLUMNS, whereClause,
	selection, null, null, null)) {
	return mConverter.convertCursor(mSiteMapManager, resultCursor, baseRank);
	}
	}

	/**
	* Builds the SQLite WHERE clause that matches all matchColumns for a single query.
	*
	* @param matchColumns List of columns that will be used for matching.
	* @return The constructed WHERE clause.
	*/
	private static String buildSingleWordWhereClause(String[] matchColumns) {
	StringBuilder sb = new StringBuilder(" (");
	final int count = matchColumns.length;
	for (int n = 0; n < count; n++) {
	sb.append(matchColumns[n]);
	sb.append(" like ? ");
	if (n < count - 1) {
	sb.append(" OR ");
	}
	}
	sb.append(") AND enabled = 1");
	return sb.toString();
	}

	/**
	* Builds the SQLite WHERE clause that matches all matchColumns to two different queries.
	*
	* @param matchColumns List of columns that will be used for matching.
	* @return The constructed WHERE clause.
	*/
	private static String buildTwoWordWhereClause(String[] matchColumns) {
	StringBuilder sb = new StringBuilder(" (");
	final int count = matchColumns.length;
	for (int n = 0; n < count; n++) {
	sb.append(matchColumns[n]);
	sb.append(" like ? OR ");
	sb.append(matchColumns[n]);
	sb.append(" like ?");
	if (n < count - 1) {
	sb.append(" OR ");
	}
	}
	sb.append(") AND enabled = 1");
	return sb.toString();
	}

	/**
	* Fills out the selection array to match the query as the prefix of a single word.
	*
	* @param size is the number of columns to be matched.
	*/
	private String[] buildSingleWordSelection(String query, int size) {
	String[] selection = new String[size];

	for(int i = 0; i < size; i ++) {
	selection[i] = query;
	}
	return selection;
	}

	/**
	* Fills out the selection array to match the query as the prefix of a word.
	*
	* @param size is twice the number of columns to be matched. The first match is for the prefix
	* of the first word in the column. The second match is for any subsequent word
	* prefix match.
	*/
	private String[] buildAnyWordSelection(int size) {
	String[] selection = new String[size];
	final String query = mQueryText + "%";
	final String subStringQuery = "% " + mQueryText + "%";

	for(int i = 0; i < (size - 1); i += 2) {
	selection[i] = query;
	selection[i + 1] = subStringQuery;
	}
	return selection;
	}
	}