001: // kelondroRAIOChunks.java
002: // -----------------------
003: // part of The Kelondro Database
004: // (C) by Michael Peter Christen; mc@anomic.de
005: // first published on http://www.anomic.de
006: // Frankfurt, Germany, 2005
007: // created: 11.12.2004
008: //
009: // This program is free software; you can redistribute it and/or modify
010: // it under the terms of the GNU General Public License as published by
011: // the Free Software Foundation; either version 2 of the License, or
012: // (at your option) any later version.
013: //
014: // This program is distributed in the hope that it will be useful,
015: // but WITHOUT ANY WARRANTY; without even the implied warranty of
016: // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
017: // GNU General Public License for more details.
018: //
019: // You should have received a copy of the GNU General Public License
020: // along with this program; if not, write to the Free Software
021: // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
022: //
023: // Using this software in any meaning (reading, learning, copying, compiling,
024: // running) means that you agree that the Author(s) is (are) not responsible
025: // for cost, loss of data or any harm that may be caused directly or indirectly
026: // by usage of this softare or this documentation. The usage of this software
027: // is on your own risk. The installation and usage (starting/running) of this
028: // software may allow other people or application to access your computer and
029: // any attached devices and is highly dependent on the configuration of the
030: // software which must be done by the user of the software; the author(s) is
031: // (are) also not responsible for proper configuration and usage of the
032: // software, even if provoked by documentation provided together with
033: // the software.
034: //
035: // Any changes to this file according to the GPL as documented in the file
036: // gpl.txt aside this file in the shipment you received can be done to the
037: // lines that follows this copyright notice here, but changes must not be
038: // done inside the copyright notive above. A re-distribution must contain
039: // the intact and unchanged copyright notice.
040: // Contributions and changes to the program code must be marked as such.
041:
042: package de.anomic.kelondro;
043:
044: import java.io.IOException;
045:
046: public final class kelondroRAIOChunks extends kelondroAbstractIOChunks
047: implements kelondroIOChunks {
048:
049: protected kelondroRA ra;
050:
051: public kelondroRAIOChunks(kelondroRA ra, String name) {
052: this .name = name;
053: this .ra = ra;
054: }
055:
056: public kelondroRA getRA() {
057: return this .ra;
058: }
059:
060: public synchronized long length() throws IOException {
061: return ra.length();
062: }
063:
064: public synchronized int read(long pos, byte[] b, int off, int len)
065: throws IOException {
066: if (len == 0)
067: return 0;
068: this .ra.seek(pos);
069: long available = ra.available();
070: if (available >= len) {
071: return ra.read(b, off, len);
072: } else if (available == 0) {
073: return -1;
074: } else {
075: return ra.read(b, off, (int) available);
076: }
077: }
078:
079: public synchronized void write(long pos, byte[] b, int off, int len)
080: throws IOException {
081: this .ra.seek(pos);
082: this .ra.write(b, off, len);
083: }
084:
085: public void commit() throws IOException {
086: // do nothing here
087: // this method is used to flush write-buffers
088: }
089:
090: public synchronized void close() throws IOException {
091: if (this .ra != null)
092: this .ra.close();
093: this .ra = null;
094: }
095:
096: protected void finalize() throws Throwable {
097: if (this.ra != null)
098: this.close();
099: super.finalize();
100: }
101:
102: }
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