Mercurial > 510Connectbot
annotate app/src/main/java/org/tn5250j/framework/tn5250/Stream5250.java @ 524:609b142218bc
Added tag stable-1.9.4-7 for changeset 775a81a78a2b
| author | Carl Byington <carl@five-ten-sg.com> |
|---|---|
| date | Fri, 31 May 2024 21:14:55 -0600 |
| parents | 8fa8e73e2f5c |
| children |
| rev | line source |
|---|---|
| 3 | 1 /** |
| 2 * Title: tn5250J | |
| 3 * Copyright: Copyright (c) 2001 | |
| 4 * Company: | |
| 5 * @author Kenneth J. Pouncey | |
| 6 * @version 0.4 | |
| 7 * | |
| 8 * Description: | |
| 9 * | |
| 10 * This program is free software; you can redistribute it and/or modify | |
| 11 * it under the terms of the GNU General Public License as published by | |
| 12 * the Free Software Foundation; either version 2, or (at your option) | |
| 13 * any later version. | |
| 14 * | |
| 15 * This program is distributed in the hope that it will be useful, | |
| 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 18 * GNU General Public License for more details. | |
| 19 * | |
| 20 * You should have received a copy of the GNU General Public License | |
| 21 * along with this software; see the file COPYING. If not, write to | |
| 22 * the Free Software Foundation, Inc., 59 Temple Place, Suite 330, | |
| 23 * Boston, MA 02111-1307 USA | |
| 24 * | |
| 25 */ | |
| 26 package org.tn5250j.framework.tn5250; | |
| 27 | |
| 28 public class Stream5250 { | |
|
445
8fa8e73e2f5c
update to tn5250j version 0.7.7, svn r1270
Carl Byington <carl@five-ten-sg.com>
parents:
438
diff
changeset
|
29 public static final int OPCODE_OFFSET = 9; |
| 3 | 30 |
| 31 public int streamSize; | |
| 32 public int opCode; | |
| 33 public int dataStart; | |
| 34 public int pos; | |
| 35 public byte buffer[]; | |
| 36 | |
| 37 public Stream5250(byte abyte0[]) { | |
| 38 buffer = abyte0; | |
| 39 // size without end of record 0xFF 0xEF | |
| 40 streamSize = (abyte0[0] & 0xff) << 8 | abyte0[1] & 0xff; | |
| 41 opCode = abyte0[9]; | |
| 42 dataStart = 6 + abyte0[6]; | |
| 43 pos = dataStart; | |
| 44 } | |
| 45 | |
| 46 public Stream5250() { | |
| 112 | 47 buffer = null; |
| 48 streamSize = 0; | |
| 49 opCode = 0; | |
| 50 dataStart = 0; | |
| 51 pos = dataStart; | |
| 52 } | |
| 3 | 53 |
| 54 /** | |
| 55 * This method takes a byte array and initializes the object information | |
| 56 * to be used. | |
| 112 | 57 * |
| 3 | 58 * @param abyte0 |
| 59 */ | |
| 60 public void initialize(byte abyte0[]) { | |
| 112 | 61 buffer = abyte0; |
| 62 // size without end of record 0xFF 0xEF | |
| 63 streamSize = (abyte0[0] & 0xff) << 8 | abyte0[1] & 0xff; | |
|
445
8fa8e73e2f5c
update to tn5250j version 0.7.7, svn r1270
Carl Byington <carl@five-ten-sg.com>
parents:
438
diff
changeset
|
64 opCode = abyte0[OPCODE_OFFSET]; |
| 112 | 65 dataStart = 6 + abyte0[6]; |
| 66 pos = dataStart; | |
| 3 | 67 } |
| 112 | 68 |
| 3 | 69 public final int getOpCode() { |
| 70 return opCode; | |
| 71 } | |
| 72 | |
| 73 public final byte getNextByte() | |
| 112 | 74 throws Exception { |
| 75 if (buffer == null || pos > buffer.length) | |
| 3 | 76 throw new Exception("Buffer length exceeded: " + pos); |
| 77 else | |
| 78 return buffer[pos++]; | |
| 79 } | |
| 80 | |
| 81 public final void setPrevByte() | |
| 112 | 82 throws Exception { |
| 83 if (pos == 0) { | |
| 3 | 84 throw new Exception("Index equals zero."); |
| 85 } | |
| 86 else { | |
| 87 pos--; | |
| 88 return; | |
| 112 | 89 } |
| 90 } | |
| 3 | 91 |
| 112 | 92 /** |
| 93 * Returns where we are in the buffer | |
| 94 * @return position in the buffer | |
| 95 */ | |
| 96 public final int getCurrentPos() { | |
| 97 return pos; | |
| 98 } | |
| 3 | 99 |
| 112 | 100 public final byte getByteOffset(int off) |
| 101 throws Exception { | |
| 102 if (buffer == null || (pos + off) > buffer.length) | |
| 3 | 103 throw new Exception("Buffer length exceeded: " + pos); |
| 104 else | |
| 105 return buffer[pos + off]; | |
| 112 | 106 } |
| 3 | 107 |
| 112 | 108 public final boolean size() { |
| 109 return pos >= streamSize; | |
| 110 } | |
| 3 | 111 |
| 112 | |
| 112 | 113 /** |
| 114 * Determines if any more bytes are available in the buffer to be processed. | |
| 115 * @return yes or no | |
| 116 */ | |
| 117 public final boolean hasNext() { | |
| 3 | 118 // return pos >= buffer.length; |
| 112 | 119 return pos < streamSize; |
| 120 } | |
| 3 | 121 |
| 112 | 122 /** |
| 123 * This routine will retrieve a segment based on the first two bytes being | |
| 124 * the length of the segment. | |
| 125 * | |
| 126 * @return a new byte array containing the bytes of the segment. | |
| 127 * @throws Exception | |
| 128 */ | |
| 129 public final byte[] getSegment() throws Exception { | |
| 130 // The first two bytes contain the length of the segment. | |
| 131 int length = ((buffer[pos] & 0xff) << 8 | (buffer[pos + 1] & 0xff)); | |
| 132 // allocate space for it. | |
| 133 byte[] segment = new byte[length]; | |
| 134 getSegment(segment, length, true); | |
| 135 return segment; | |
| 136 } | |
| 3 | 137 |
| 138 | |
| 112 | 139 /** |
| 140 * This routine will retrieve a byte array based on the first two bytes being | |
| 141 * the length of the segment. | |
| 142 * | |
| 143 * @param segment - byte array | |
| 144 * @param length - length of segment to return | |
| 145 * @param adjustPos - adjust the position of the buffer to the end of the seg | |
| 146 * ment | |
| 147 * @throws Exception | |
| 148 */ | |
| 149 public final void getSegment(byte[] segment, int length, boolean adjustPos) | |
| 150 throws Exception { | |
| 151 // If the length is larger than what is available throw an exception | |
| 152 if ((pos + length) > buffer.length) | |
| 153 throw new Exception("Buffer length exceeded: start " + pos | |
| 154 + " length " + length); | |
| 3 | 155 |
| 112 | 156 // use the system array copy to move the bytes from the buffer |
| 157 // to the allocated byte array | |
| 158 System.arraycopy(buffer, pos, segment, 0, length); | |
| 3 | 159 |
| 112 | 160 // update the offset to be after the segment so the next byte can be read |
| 161 if (adjustPos) | |
| 162 pos += length; | |
| 163 } | |
| 3 | 164 |
| 165 } |