001: package com.quadcap.sql.file;
002:
003: /* Copyright 1999 - 2003 Quadcap Software. All rights reserved.
004: *
005: * This software is distributed under the Quadcap Free Software License.
006: * This software may be used or modified for any purpose, personal or
007: * commercial. Open Source redistributions are permitted. Commercial
008: * redistribution of larger works derived from, or works which bundle
009: * this software requires a "Commercial Redistribution License"; see
010: * http://www.quadcap.com/purchase.
011: *
012: * Redistributions qualify as "Open Source" under one of the following terms:
013: *
014: * Redistributions are made at no charge beyond the reasonable cost of
015: * materials and delivery.
016: *
017: * Redistributions are accompanied by a copy of the Source Code or by an
018: * irrevocable offer to provide a copy of the Source Code for up to three
019: * years at the cost of materials and delivery. Such redistributions
020: * must allow further use, modification, and redistribution of the Source
021: * Code under substantially the same terms as this license.
022: *
023: * Redistributions of source code must retain the copyright notices as they
024: * appear in each source code file, these license terms, and the
025: * disclaimer/limitation of liability set forth as paragraph 6 below.
026: *
027: * Redistributions in binary form must reproduce this Copyright Notice,
028: * these license terms, and the disclaimer/limitation of liability set
029: * forth as paragraph 6 below, in the documentation and/or other materials
030: * provided with the distribution.
031: *
032: * The Software is provided on an "AS IS" basis. No warranty is
033: * provided that the Software is free of defects, or fit for a
034: * particular purpose.
035: *
036: * Limitation of Liability. Quadcap Software shall not be liable
037: * for any damages suffered by the Licensee or any third party resulting
038: * from use of the Software.
039: */
040:
041: import com.quadcap.util.Debug;
042: import com.quadcap.util.Util;
043:
044: /**
045: * A <code>RandomAccess</code> implementation using a byte array.
046: *
047: * @author Stan Bailes
048: */
049: public class ByteArrayRandomAccess extends RandomAccess {
050: byte[] buf;
051: int size;
052:
053: public ByteArrayRandomAccess() {
054: this .size = 0;
055: setCapacity(1024);
056: }
057:
058: public ByteArrayRandomAccess(int initialCap) {
059: this .size = 0;
060: setCapacity(initialCap);
061: }
062:
063: public ByteArrayRandomAccess(byte[] buf) {
064: this .buf = buf;
065: this .size = buf.length;
066: }
067:
068: public void reset(byte[] buf, int size) {
069: this .buf = buf;
070: this .size = size;
071: }
072:
073: public byte[] getBytes() {
074: return buf;
075: }
076:
077: final void setCapacity(long cap) {
078: if (buf == null || cap > buf.length) {
079: byte[] nbuf = new byte[(int) cap];
080: if (size > 0) {
081: System.arraycopy(buf, 0, nbuf, 0, size);
082: }
083: this .buf = nbuf;
084: }
085: }
086:
087: public byte[] toByteArray() {
088: byte[] ret = new byte[size];
089: read(0, ret, 0, size);
090: return ret;
091: }
092:
093: /**
094: * Return the size of the managed region.
095: */
096: public long size() {
097: return size;
098: }
099:
100: /**
101: * Resize the managed region.
102: */
103: public void resize(long newSize) {
104: if (newSize > buf.length) {
105: setCapacity(newSize + (newSize >> 1));
106: }
107: this .size = (int) newSize;
108: }
109:
110: /* Write <tt>len</tt> bytes from position <tt>offset</tt> in buffer
111: * <tt>buf</tt> to position <tt>pos</tt> bytes into the managed
112: * area.
113: */
114: public void write(long pos, byte[] b, int offset, int len) {
115: //#ifdef DEBUG
116: if (trace) {
117: Debug.println("BAR:write(" + pos + ", "
118: + Util.hexBytes(b, offset, len) + ")");
119: }
120: //#endif
121: System.arraycopy(b, offset, buf, (int) pos, len);
122: }
123:
124: /**
125: * Read <tt>len</tt> bytes from location <tt>pos</tt> of the region
126: * into the buffer <tt>buf</tt>, starting at <tt>offset</tt>.
127: */
128: public void read(long pos, byte[] b, int offset, int len) {
129: //#ifdef DEBUG
130: if (trace) {
131: Debug.println("BAR:read(" + pos + ", "
132: + Util.hexBytes(b, offset, len) + ")");
133: }
134: //#endif
135: System.arraycopy(buf, (int) pos, b, offset, len);
136: }
137:
138: //#ifdef DEBUG
139: static final boolean trace = false;
140:
141: //#endif
142:
143: public final void writeByte(int pos, int val) {
144: buf[pos] = (byte) (val & 0xff);
145: }
146:
147: public final int readByte(int pos) {
148: return buf[pos] & 0xff;
149: }
150:
151: /**
152: * Finalization...
153: */
154: public void close() {
155: }
156:
157: public void flush() {
158: }
159: }
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