1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.example.android.apis.os; 18 19 /** Class that implements the text to morse code coversion */ 20 class MorseCodeConverter { 21 private static final long SPEED_BASE = 100; 22 static final long DOT = SPEED_BASE; 23 static final long DASH = SPEED_BASE * 3; 24 static final long GAP = SPEED_BASE; 25 static final long LETTER_GAP = SPEED_BASE * 3; 26 static final long WORD_GAP = SPEED_BASE * 7; 27 28 /** The characters from 'A' to 'Z' */ 29 private static final long[][] LETTERS = new long[][] { 30 /* A */ new long[] { DOT, GAP, DASH }, 31 /* B */ new long[] { DASH, GAP, DOT, GAP, DOT, GAP, DOT }, 32 /* C */ new long[] { DASH, GAP, DOT, GAP, DASH, GAP, DOT }, 33 /* D */ new long[] { DASH, GAP, DOT, GAP, DOT }, 34 /* E */ new long[] { DOT }, 35 /* F */ new long[] { DOT, GAP, DOT, GAP, DASH, GAP, DOT }, 36 /* G */ new long[] { DASH, GAP, DASH, GAP, DOT }, 37 /* H */ new long[] { DOT, GAP, DOT, GAP, DOT, GAP, DOT }, 38 /* I */ new long[] { DOT, GAP, DOT }, 39 /* J */ new long[] { DOT, GAP, DASH, GAP, DASH, GAP, DASH }, 40 /* K */ new long[] { DASH, GAP, DOT, GAP, DASH }, 41 /* L */ new long[] { DOT, GAP, DASH, GAP, DOT, GAP, DOT }, 42 /* M */ new long[] { DASH, GAP, DASH }, 43 /* N */ new long[] { DASH, GAP, DOT }, 44 /* O */ new long[] { DASH, GAP, DASH, GAP, DASH }, 45 /* P */ new long[] { DOT, GAP, DASH, GAP, DASH, GAP, DOT }, 46 /* Q */ new long[] { DASH, GAP, DASH, GAP, DOT, GAP, DASH }, 47 /* R */ new long[] { DOT, GAP, DASH, GAP, DOT }, 48 /* S */ new long[] { DOT, GAP, DOT, GAP, DOT }, 49 /* T */ new long[] { DASH }, 50 /* U */ new long[] { DOT, GAP, DOT, GAP, DASH }, 51 /* V */ new long[] { DOT, GAP, DOT, GAP, DOT, GAP, DASH }, 52 /* W */ new long[] { DOT, GAP, DASH, GAP, DASH }, 53 /* X */ new long[] { DASH, GAP, DOT, GAP, DOT, GAP, DASH }, 54 /* Y */ new long[] { DASH, GAP, DOT, GAP, DASH, GAP, DASH }, 55 /* Z */ new long[] { DASH, GAP, DASH, GAP, DOT, GAP, DOT }, 56 }; 57 58 /** The characters from '0' to '9' */ 59 private static final long[][] NUMBERS = new long[][] { 60 /* 0 */ new long[] { DASH, GAP, DASH, GAP, DASH, GAP, DASH, GAP, DASH }, 61 /* 1 */ new long[] { DOT, GAP, DASH, GAP, DASH, GAP, DASH, GAP, DASH }, 62 /* 2 */ new long[] { DOT, GAP, DOT, GAP, DASH, GAP, DASH, GAP, DASH }, 63 /* 3 */ new long[] { DOT, GAP, DOT, GAP, DOT, GAP, DASH, GAP, DASH }, 64 /* 4 */ new long[] { DOT, GAP, DOT, GAP, DOT, GAP, DOT, GAP, DASH }, 65 /* 5 */ new long[] { DOT, GAP, DOT, GAP, DOT, GAP, DOT, GAP, DOT }, 66 /* 6 */ new long[] { DASH, GAP, DOT, GAP, DOT, GAP, DOT, GAP, DOT }, 67 /* 7 */ new long[] { DASH, GAP, DASH, GAP, DOT, GAP, DOT, GAP, DOT }, 68 /* 8 */ new long[] { DASH, GAP, DASH, GAP, DASH, GAP, DOT, GAP, DOT }, 69 /* 9 */ new long[] { DASH, GAP, DASH, GAP, DASH, GAP, DASH, GAP, DOT }, 70 }; 71 72 private static final long[] ERROR_GAP = new long[] { GAP }; 73 74 /** Return the pattern data for a given character */ 75 static long[] pattern(char c) { 76 if (c >= 'A' && c <= 'Z') { 77 return LETTERS[c - 'A']; 78 } 79 if (c >= 'a' && c <= 'z') { 80 return LETTERS[c - 'a']; 81 } 82 else if (c >= '0' && c <= '9') { 83 return NUMBERS[c - '0']; 84 } 85 else { 86 return ERROR_GAP; 87 } 88 } 89 90 static long[] pattern(String str) { 91 boolean lastWasWhitespace; 92 int strlen = str.length(); 93 94 // Calculate how long our array needs to be. 95 int len = 1; 96 lastWasWhitespace = true; 97 for (int i=0; i<strlen; i++) { 98 char c = str.charAt(i); 99 if (Character.isWhitespace(c)) { 100 if (!lastWasWhitespace) { 101 len++; 102 lastWasWhitespace = true; 103 } 104 } else { 105 if (!lastWasWhitespace) { 106 len++; 107 } 108 lastWasWhitespace = false; 109 len += pattern(c).length; 110 } 111 } 112 113 // Generate the pattern array. Note that we put an extra element of 0 114 // in at the beginning, because the pattern always starts with the pause, 115 // not with the vibration. 116 long[] result = new long[len+1]; 117 result[0] = 0; 118 int pos = 1; 119 lastWasWhitespace = true; 120 for (int i=0; i<strlen; i++) { 121 char c = str.charAt(i); 122 if (Character.isWhitespace(c)) { 123 if (!lastWasWhitespace) { 124 result[pos] = WORD_GAP; 125 pos++; 126 lastWasWhitespace = true; 127 } 128 } else { 129 if (!lastWasWhitespace) { 130 result[pos] = LETTER_GAP; 131 pos++; 132 } 133 lastWasWhitespace = false; 134 long[] letter = pattern(c); 135 System.arraycopy(letter, 0, result, pos, letter.length); 136 pos += letter.length; 137 } 138 } 139 return result; 140 } 141 } 142
