/*
*
*
* Portions Copyright 2000-2007 Sun Microsystems, Inc. All Rights
* Reserved. Use is subject to license terms.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 only, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License version 2 for more details (a copy is
* included at /legal/license.txt).
*
* You should have received a copy of the GNU General Public License
* version 2 along with this work; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
* Clara, CA 95054 or visit www.sun.com if you need additional
* information or have any questions.
*
* Copyright 2000 Motorola, Inc. All Rights Reserved.
* This notice does not imply publication.
*/
package com.sun.midp.rms;
import javax.microedition.rms.RecordStoreException;
/**
* A class implementing record store utility functions.
*/
public class RecordStoreUtil {
/**
* A convenience method for converting a byte array into
* an int (assumes big-endian byte ordering).
*
* @param data the byte array returned from the database.
* @param offset the offset into the array of the first byte to start from.
*
* @return an int corresponding to the first four bytes
* of the array passed in.
*/
static int getInt(byte[] data, int offset) {
int r = data[offset++];
r = (r << 8) | ((int)(data[offset++]) & 0xff);
r = (r << 8) | ((int)(data[offset++]) & 0xff);
r = (r << 8) | ((int)(data[offset++]) & 0xff);
return r;
}
/**
* A convenience method for converting a byte array into
* a long (assumes big-endian byte ordering).
*
* @param data the byte array returned from the database.
* @param offset the offset into the array of the first byte to start from.
* @return a long corresponding to the first eight bytes
* of the array passed in.
*/
static long getLong(byte[] data, int offset) {
long r = data[offset++];
r = (r << 8) | ((long)(data[offset++]) & 0xff);
r = (r << 8) | ((long)(data[offset++]) & 0xff);
r = (r << 8) | ((long)(data[offset++]) & 0xff);
r = (r << 8) | ((long)(data[offset++]) & 0xff);
r = (r << 8) | ((long)(data[offset++]) & 0xff);
r = (r << 8) | ((long)(data[offset++]) & 0xff);
r = (r << 8) | ((long)(data[offset++]) & 0xff);
return r;
}
/**
* A convenience method for converting an integer into
* a byte array.
*
* @param i the integer to turn into a byte array.
* @param data a place to store the bytes of <code>i</code>.
* @param offset starting point within <code>data<code> to
* store <code>i</code>.
*
* @return the number of bytes written to the array.
*/
static int putInt(int i, byte[] data, int offset) {
data[offset++] = (byte)((i >> 24) & 0xff);
data[offset++] = (byte)((i >> 16) & 0xff);
data[offset++] = (byte)((i >> 8) & 0xff);
data[offset] = (byte)(i & 0xff);
return 4;
}
/**
* A convenience method for converting a long into
* a byte array.
*
* @param l the <code>long<code> to turn into a byte array.
* @param data a place to store the bytes of <code>l</code>.
* @param offset Starting point within <code>data</code> to
* store <code>l</code>.
*
* @return the number of bytes written to the array.
*/
static int putLong(long l, byte[] data, int offset) {
data[offset++] = (byte)((l >> 56) & 0xff);
data[offset++] = (byte)((l >> 48) & 0xff);
data[offset++] = (byte)((l >> 40) & 0xff);
data[offset++] = (byte)((l >> 32) & 0xff);
data[offset++] = (byte)((l >> 24) & 0xff);
data[offset++] = (byte)((l >> 16) & 0xff);
data[offset++] = (byte)((l >> 8) & 0xff);
data[offset] = (byte)(l & 0xff);
return 8;
}
/**
* A convenience method for calculating the block size given the data size.
*
* @param dataSize the size of the data in the block.
*
* @return an int corresponding to the size of the block padded to
* a multiple of the BLOCK HEADER SIZE.
*/
static int calculateBlockSize(int dataSize) {
final int block_header_size = AbstractRecordStoreImpl.BLOCK_HEADER_SIZE;
int remainder = dataSize % block_header_size; // & 0x07;
if (remainder == 0) {
return dataSize + block_header_size;
} else {
return dataSize + (block_header_size - remainder) +
block_header_size;
}
}
/**
* Looks to see if the storage file for record store
* identified by <code>uidPath</code> exists
*
* @param suiteId ID of the MIDlet suite that owns the record store
* @param name name of the record store
* @param extension the extension for the record store file
*
* @return true if the file exists, false if it does not.
*/
native static boolean exists(int suiteId, String name, int extension);
/**
* Removes the storage file for record store <code>filename</code>
* if it exists.
*
* @param suiteId ID of the MIDlet suite that owns the record store
* @param name name of the record store
* @param extension the extension for the record store file
*
* @throws RecordStoreException if deletion encountered an error
* internally.
*/
native static void deleteFile(int suiteId, String name, int extension)
throws RecordStoreException;
/**
* Removes record store file without throwing an exception on failure.
*
* @param suiteId ID of the MIDlet suite that owns the record store
* @param name name of the record store
* @param extension the extension for the record store file
*
* @return <code>true</code> if file was found and deleted successfully,
* <code>false</code> otherwise.
*/
static boolean quietDeleteFile(int suiteId, String name, int extension) {
try {
deleteFile(suiteId, name, extension);
} catch (Throwable t) {
return false;
}
return true;
}
}
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