| 1 | package fr.sii.ogham.sms.splitter; | |
| 2 | ||
| 3 | import java.util.Random; | |
| 4 | ||
| 5 | /** | |
| 6 | * In the cellular phone industry, mobile phones and their networks sometimes | |
| 7 | * support concatenated short message service (or concatenated SMS) to overcome | |
| 8 | * the limitation on the number of characters that can be sent in a single SMS | |
| 9 | * text message transmission (which is usually 160). Using this method, long | |
| 10 | * messages are split into smaller messages by the sending device and recombined | |
| 11 | * at the receiving end. Each message is then billed separately. When the | |
| 12 | * feature works properly, it is nearly transparent to the user, appearing as a | |
| 13 | * single long text message. | |
| 14 | * | |
| 15 | * <p> | |
| 16 | * One way of sending concatenated SMS (CSMS) is to split the message into 153 | |
| 17 | * 7-bit character parts (134 octets), and sending each part with a User Data | |
| 18 | * Header (UDH) tacked onto the beginning. A UDH can be used for various | |
| 19 | * purposes and its contents and size varies accordingly, but a UDH for | |
| 20 | * concatenating SMSes look like this: | |
| 21 | * | |
| 22 | * <ul> | |
| 23 | * <li>Field 1 (1 octet): Length of User Data Header, in this case 05.</li> | |
| 24 | * <li>Field 2 (1 octet): Information Element Identifier, equal to 00 | |
| 25 | * (Concatenated short messages, 8-bit reference number)</li> | |
| 26 | * <li>Field 3 (1 octet): Length of the header, excluding the first two fields; | |
| 27 | * equal to 03</li> | |
| 28 | * <li>Field 4 (1 octet): 00-FF, CSMS reference number, must be same for all the | |
| 29 | * SMS parts in the CSMS</li> | |
| 30 | * <li>Field 5 (1 octet): 00-FF, total number of parts. The value shall remain | |
| 31 | * constant for every short message which makes up the concatenated short | |
| 32 | * message. If the value is zero then the receiving entity shall ignore the | |
| 33 | * whole information element</li> | |
| 34 | * <li>Field 6 (1 octet): 00-FF, this part's number in the sequence. The value | |
| 35 | * shall start at 1 and increment for every short message which makes up the | |
| 36 | * concatenated short message. If the value is zero or greater than the value in | |
| 37 | * Field 5 then the receiving entity shall ignore the whole information element. | |
| 38 | * [ETSI Specification: GSM 03.40 Version 5.3.0: July 1996]</li> | |
| 39 | * </ul> | |
| 40 | * | |
| 41 | * <p> | |
| 42 | * It is possible to use a 16 bit CSMS reference number in order to reduce the | |
| 43 | * probability that two different concatenated messages are sent with identical | |
| 44 | * reference numbers to a receiver. In this case, the User Data Header shall be: | |
| 45 | * | |
| 46 | * <ul> | |
| 47 | * <li>Field 1 (1 octet): Length of User Data Header (UDL), in this case | |
| 48 | * 06.</li> | |
| 49 | * <li>Field 2 (1 octet): Information Element Identifier, equal to 08 | |
| 50 | * (Concatenated short messages, 16-bit reference number)</li> | |
| 51 | * <li>Field 3 (1 octet): Length of the header, excluding the first two fields; | |
| 52 | * equal to 04</li> | |
| 53 | * <li>Field 4 (2 octets): 0000-FFFF, CSMS reference number, must be same for | |
| 54 | * all the SMS parts in the CSMS</li> | |
| 55 | * <li>Field 5 (1 octet): 00-FF, total number of parts. The value shall remain | |
| 56 | * constant for every short message which makes up the concatenated short | |
| 57 | * message. If the value is zero then the receiving entity shall ignore the | |
| 58 | * whole information element</li> | |
| 59 | * <li>Field 6 (1 octet): 00-FF, this part's number in the sequence. The value | |
| 60 | * shall start at 1 and increment for every short message which makes up the | |
| 61 | * concatenated short message. If the value is zero or greater than the value in | |
| 62 | * Field 5 then the receiving entity shall ignore the whole information element. | |
| 63 | * [ETSI Specification: GSM 03.40 Version 5.3.0: July 1996]</li> | |
| 64 | * </ul> | |
| 65 | * | |
| 66 | * <p> | |
| 67 | * This implementation generates a value using {@link Random} utility. | |
| 68 | * | |
| 69 | * @author Aurélien Baudet | |
| 70 | * | |
| 71 | */ | |
| 72 | public class RandomReferenceNumberGenerator implements ReferenceNumberGenerator { | |
| 73 | private final Random random; | |
| 74 | private final int length; | |
| 75 | ||
| 76 | /** | |
| 77 | * Uses a default {@link Random} to generate random reference numbers. The | |
| 78 | * generated reference is only one octet length. | |
| 79 | * | |
| 80 | * <p> | |
| 81 | * If you want a custom number generation, use | |
| 82 | * {@link #RandomReferenceNumberGenerator(Random)}. | |
| 83 | */ | |
| 84 | @SuppressWarnings("squid:S2245") | |
| 85 | public RandomReferenceNumberGenerator() { | |
| 86 | this(new Random()); | |
| 87 | } | |
| 88 | ||
| 89 | /** | |
| 90 | * Use the provided {@link Random} to generate random reference numbers. The | |
| 91 | * generated reference is only one octet length. | |
| 92 | * | |
| 93 | * <p> | |
| 94 | * If you want to generate a reference number of two octets, use | |
| 95 | * {@link #RandomReferenceNumberGenerator(Random, int)}. | |
| 96 | * | |
| 97 | * @param random | |
| 98 | * used to generate random numbers | |
| 99 | */ | |
| 100 | public RandomReferenceNumberGenerator(Random random) { | |
| 101 | this(random, 1); | |
| 102 | } | |
| 103 | ||
| 104 | /** | |
| 105 | * Use the provided {@link Random} to generate random reference number byte | |
| 106 | * arrays. Each reference number byte array has a size of {@code length} | |
| 107 | * parameter. | |
| 108 | * | |
| 109 | * @param random | |
| 110 | * used to generate random numbers | |
| 111 | * @param length | |
| 112 | * the number of octets for each reference number | |
| 113 | */ | |
| 114 | public RandomReferenceNumberGenerator(Random random, int length) { | |
| 115 | super(); | |
| 116 | this.random = random; | |
| 117 | this.length = length; | |
| 118 | } | |
| 119 | ||
| 120 | @Override | |
| 121 | public byte[] generateReferenceNumber() { | |
| 122 | byte[] referenceNumber = new byte[length]; | |
| 123 |
2
1. generateReferenceNumber : removed call to java/util/Random::nextBytes → NO_COVERAGE 2. generateReferenceNumber : removed call to java/util/Random::nextBytes → SURVIVED |
random.nextBytes(referenceNumber); |
| 124 |
3
1. generateReferenceNumber : replaced return value with null for fr/sii/ogham/sms/splitter/RandomReferenceNumberGenerator::generateReferenceNumber → NO_COVERAGE 2. generateReferenceNumber : replaced return value with null for fr/sii/ogham/sms/splitter/RandomReferenceNumberGenerator::generateReferenceNumber → KILLED 3. generateReferenceNumber : replaced return value with null for fr/sii/ogham/sms/splitter/RandomReferenceNumberGenerator::generateReferenceNumber → KILLED |
return referenceNumber; |
| 125 | } | |
| 126 | ||
| 127 | } | |
Mutations | ||
| 123 |
1.1 2.2 |
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| 124 |
1.1 2.2 3.3 |