SQLite Android Bindings
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/*
 * Copyright (C) 2006 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.
 */
/*
** Modified to support SQLite extensions by the SQLite developers: 
** sqlite-dev@sqlite.org.
*/

package org.sqlite.database;
import android.database.Cursor;
import android.database.CursorWindow;

/* import org.apache.commons.codec.binary.Hex; */

import android.content.ContentValues;
import android.content.Context;
import android.content.OperationApplicationException;
import org.sqlite.database.sqlite.SQLiteAbortException;
import org.sqlite.database.sqlite.SQLiteConstraintException;
import org.sqlite.database.sqlite.SQLiteDatabase;
import org.sqlite.database.sqlite.SQLiteDatabaseCorruptException;
import org.sqlite.database.sqlite.SQLiteDiskIOException;
import org.sqlite.database.sqlite.SQLiteException;
import org.sqlite.database.sqlite.SQLiteFullException;
import org.sqlite.database.sqlite.SQLiteProgram;
import org.sqlite.database.sqlite.SQLiteStatement;
import org.sqlite.os.OperationCanceledException;
import android.os.Parcel;
import android.os.ParcelFileDescriptor;
import android.text.TextUtils;
import android.util.Log;

import java.io.FileNotFoundException;
import java.io.PrintStream;
import java.text.Collator;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;

/**
 * Static utility methods for dealing with databases and {@link Cursor}s.
 */
public class ExtraUtils {
    private static final String TAG = "ExtraUtils";

    private static final boolean DEBUG = false;

    /** One of the values returned by {@link #getSqlStatementType(String)}. */
    public static final int STATEMENT_SELECT = 1;
    /** One of the values returned by {@link #getSqlStatementType(String)}. */
    public static final int STATEMENT_UPDATE = 2;
    /** One of the values returned by {@link #getSqlStatementType(String)}. */
    public static final int STATEMENT_ATTACH = 3;
    /** One of the values returned by {@link #getSqlStatementType(String)}. */
    public static final int STATEMENT_BEGIN = 4;
    /** One of the values returned by {@link #getSqlStatementType(String)}. */
    public static final int STATEMENT_COMMIT = 5;
    /** One of the values returned by {@link #getSqlStatementType(String)}. */
    public static final int STATEMENT_ABORT = 6;
    /** One of the values returned by {@link #getSqlStatementType(String)}. */
    public static final int STATEMENT_PRAGMA = 7;
    /** One of the values returned by {@link #getSqlStatementType(String)}. */
    public static final int STATEMENT_DDL = 8;
    /** One of the values returned by {@link #getSqlStatementType(String)}. */
    public static final int STATEMENT_UNPREPARED = 9;
    /** One of the values returned by {@link #getSqlStatementType(String)}. */
    public static final int STATEMENT_OTHER = 99;

    /**
     * Returns column index of "_id" column, or -1 if not found.
     */
    public static int findRowIdColumnIndex(String[] columnNames) {
        int length = columnNames.length;
        for (int i = 0; i < length; i++) {
            if (columnNames[i].equals("_id")) {
                return i;
            }
        }
        return -1;
    }

    /**
     * Picks a start position for {@link Cursor#fillWindow} such that the
     * window will contain the requested row and a useful range of rows
     * around it.
     *
     * When the data set is too large to fit in a cursor window, seeking the
     * cursor can become a very expensive operation since we have to run the
     * query again when we move outside the bounds of the current window.
     *
     * We try to choose a start position for the cursor window such that
     * 1/3 of the window's capacity is used to hold rows before the requested
     * position and 2/3 of the window's capacity is used to hold rows after the
     * requested position.
     *
     * @param cursorPosition The row index of the row we want to get.
     * @param cursorWindowCapacity The estimated number of rows that can fit in
     * a cursor window, or 0 if unknown.
     * @return The recommended start position, always less than or equal to
     * the requested row.
     * @hide
     */
    public static int cursorPickFillWindowStartPosition(
            int cursorPosition, int cursorWindowCapacity) {
        return Math.max(cursorPosition - cursorWindowCapacity / 3, 0);
    }

    /**
     * Returns data type of the given object's value.
     *<p>
     * Returned values are
     * <ul>
     *   <li>{@link Cursor#FIELD_TYPE_NULL}</li>
     *   <li>{@link Cursor#FIELD_TYPE_INTEGER}</li>
     *   <li>{@link Cursor#FIELD_TYPE_FLOAT}</li>
     *   <li>{@link Cursor#FIELD_TYPE_STRING}</li>
     *   <li>{@link Cursor#FIELD_TYPE_BLOB}</li>
     *</ul>
     *</p>
     *
     * @param obj the object whose value type is to be returned
     * @return object value type
     */
    public static int getTypeOfObject(Object obj) {
        if (obj == null) {
            return Cursor.FIELD_TYPE_NULL;
        } else if (obj instanceof byte[]) {
            return Cursor.FIELD_TYPE_BLOB;
        } else if (obj instanceof Float || obj instanceof Double) {
            return Cursor.FIELD_TYPE_FLOAT;
        } else if (obj instanceof Long || obj instanceof Integer
                || obj instanceof Short || obj instanceof Byte) {
            return Cursor.FIELD_TYPE_INTEGER;
        } else {
            return Cursor.FIELD_TYPE_STRING;
        }
    }

    /**
     * Utility method to run the query on the db and return the value in the
     * first column of the first row.
     */
    public static long longForQuery(
        SQLiteDatabase db, String query, String[] selectionArgs
    ) {
        SQLiteStatement prog = db.compileStatement(query);
        try {
            return longForQuery(prog, selectionArgs);
        } finally {
            prog.close();
        }
    }

    /**
     * Utility method to run the pre-compiled query and return the value in the
     * first column of the first row.
     */
    public static long longForQuery(
        SQLiteStatement prog, String[] selectionArgs
    ) {
        prog.bindAllArgsAsStrings(selectionArgs);
        return prog.simpleQueryForLong();
    }
}