Peter Kriens | de0b31b | 2010-05-20 15:18:18 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Licensed to the Apache Software Foundation (ASF) under one |
| 3 | * or more contributor license agreements. See the NOTICE file |
| 4 | * distributed with this work for additional information |
| 5 | * regarding copyright ownership. The ASF licenses this file |
| 6 | * to you under the Apache License, Version 2.0 (the |
| 7 | * "License"); you may not use this file except in compliance |
| 8 | * with the License. You may obtain a copy of the License at |
| 9 | * |
| 10 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 11 | * |
| 12 | * Unless required by applicable law or agreed to in writing, |
| 13 | * software distributed under the License is distributed on an |
| 14 | * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| 15 | * KIND, either express or implied. See the License for the |
| 16 | * specific language governing permissions and limitations |
| 17 | * under the License. |
| 18 | */ |
| 19 | package org.apache.felix.service.terminal; |
| 20 | |
| 21 | import java.io.*; |
| 22 | |
| 23 | /** |
| 24 | * Terminal. |
| 25 | * |
| 26 | * The Terminal interface describes a minimal terminal that can easily be mapped |
| 27 | * to command line editing tools. |
| 28 | * |
| 29 | * A Terminal is associated with an Input Stream and an Output Stream. The Input |
| 30 | * Stream represents the keyboard and the Output Stream the screen. |
| 31 | * |
| 32 | * A terminal does not block the input, each character is returned as it is |
| 33 | * typed, no buffering or line editing takes place, characters are also not |
| 34 | * echoed. However, the Input Stream is not restricted to bytes only, it can |
| 35 | * also return translated key strokes. Integers from 1000 are used for those. |
| 36 | * Not all keys have to be supported by an implementation. |
| 37 | * |
| 38 | * A number of functions is provided to move the cursor and erase |
| 39 | * characters/lines/screens. Any text outputed to the Output Stream is |
| 40 | * immediately added to the cursor position, which is then moved forwards. The |
| 41 | * control characters (LF,CR,TAB,BS) perform their normal actions. However lines |
| 42 | * do not wrap. Text typed that is longer than the window will not be visible, |
| 43 | * it is the responsibility of the sender to ensure this does not happen. |
| 44 | * |
| 45 | * A screen is considered to be {@link #height()} lines that each have |
| 46 | * {@link #width()} characters. For cursor positioning, the screen is assumed to |
| 47 | * be starting at 0,0 and increases its position from left to right and from top |
| 48 | * to bottom. Positioning outside the screen bounds is undefined. |
| 49 | */ |
| 50 | public interface Terminal { |
| 51 | /** |
| 52 | * Cursor up key |
| 53 | */ |
| 54 | int CURSOR_UP = 1000; |
| 55 | /** |
| 56 | * Cursor down key. |
| 57 | */ |
| 58 | int CURSOR_DOWN = 1001; |
| 59 | /** |
| 60 | * Cursors forward key. Usually right. |
| 61 | */ |
| 62 | int CURSOR_FORWARD = 1002; |
| 63 | |
| 64 | /** |
| 65 | * Cursors backward key. Usually left. |
| 66 | */ |
| 67 | int CURSOR_BACKWARD = 1003; |
| 68 | |
| 69 | /** |
| 70 | * Page up key |
| 71 | */ |
| 72 | int PAGE_UP = 1004; |
| 73 | /** |
| 74 | * Page down key |
| 75 | */ |
| 76 | int PAGE_DOWN = 1005; |
| 77 | /** |
| 78 | * Home key |
| 79 | */ |
| 80 | int HOME = 1006; |
| 81 | /** |
| 82 | * End key |
| 83 | */ |
| 84 | int END = 1007; |
| 85 | /** |
| 86 | * Insert key |
| 87 | */ |
| 88 | int INSERT = 1008; |
| 89 | /** |
| 90 | * Delete key |
| 91 | */ |
| 92 | int DELETE = 1009; |
| 93 | /** |
| 94 | * Break key |
| 95 | */ |
| 96 | int BREAK = 1009; |
| 97 | /** |
| 98 | * Function key 1 |
| 99 | */ |
| 100 | int F1 = 1101; |
| 101 | /** |
| 102 | * Function key 2 |
| 103 | */ |
| 104 | int F2 = 1102; |
| 105 | /** |
| 106 | * Function key 3 |
| 107 | */ |
| 108 | int F3 = 1103; |
| 109 | /** |
| 110 | * Function key 4 |
| 111 | */ |
| 112 | int F4 = 1104; |
| 113 | /** |
| 114 | * Function key 5 |
| 115 | */ |
| 116 | int F5 = 1105; |
| 117 | /** |
| 118 | * Function key 6 |
| 119 | */ |
| 120 | int F6 = 1106; |
| 121 | /** |
| 122 | * Function key 7 |
| 123 | */ |
| 124 | int F7 = 1107; |
| 125 | /** |
| 126 | * Function key 8 |
| 127 | */ |
| 128 | int F8 = 1108; |
| 129 | /** |
| 130 | * Function key 9 |
| 131 | */ |
| 132 | int F9 = 1109; |
| 133 | /** |
| 134 | * Function key 10 |
| 135 | */ |
| 136 | int F10 = 1110; |
| 137 | /** |
| 138 | * Function key 11 |
| 139 | */ |
| 140 | int F11 = 1111; |
| 141 | /** |
| 142 | * Function key 12 |
| 143 | */ |
| 144 | int F12 = 1112; |
| 145 | |
| 146 | enum Attribute { |
| 147 | BLINK, UNDERLINE, STRIKE_THROUGH, BOLD, DIM, REVERSED; |
| 148 | } |
| 149 | |
| 150 | enum Color { |
| 151 | NONE, BLACK, GREEN, YELLOW, MAGENTA, CYAN, BLUE, RED, WHITE; |
| 152 | } |
| 153 | |
| 154 | /** |
| 155 | * Return the associated Input Stream that represents the keyboard. Note |
| 156 | * that this InputStream can return values > 256, these characters are |
| 157 | * defined in this interface as special keys. This Input Stream should not |
| 158 | * be closed by the client. If the client is done, it should unget the |
| 159 | * services. |
| 160 | * |
| 161 | * @return the current Input Stream. |
| 162 | */ |
| 163 | InputStream getInputStream(); |
| 164 | |
| 165 | /** |
| 166 | * Return the Output Stream that is associated with the screen. Any writes |
| 167 | * Clear the complete screen and position the cursor at 0,0. |
| 168 | * |
| 169 | * @throws Exception |
| 170 | */ |
| 171 | void clear() throws Exception; |
| 172 | |
| 173 | /** |
| 174 | * Leave the cursor where it is but clear the remainder of the line. |
| 175 | */ |
| 176 | void eraseEndOfLine(); |
| 177 | |
| 178 | /** |
| 179 | * Move the cursor up one line, this must not cause a scroll if the cursor |
| 180 | * moves off the screen. |
| 181 | * |
| 182 | * @throws Exception |
| 183 | */ |
| 184 | void up() throws Exception; |
| 185 | |
| 186 | /** |
| 187 | * Move the cursor down one line, this must not cause a scroll if the |
| 188 | * cursors moves off the screen. |
| 189 | * |
| 190 | * @throws Exception |
| 191 | */ |
| 192 | void down() throws Exception; |
| 193 | |
| 194 | /** |
| 195 | * Move the cursor backward. Must not wrap to previous line. |
| 196 | * |
| 197 | * @throws Exception |
| 198 | */ |
| 199 | void backward() throws Exception; |
| 200 | |
| 201 | /** |
| 202 | * Move the cursor forward. Must not wrap to next line if the cursor becomes |
| 203 | * higher than the width. |
| 204 | * |
| 205 | * @throws Exception |
| 206 | */ |
| 207 | void forward() throws Exception; |
| 208 | |
| 209 | /** |
| 210 | * Return the actual width of the screen. Some screens can change their size |
| 211 | * and this method must return the actual width. |
| 212 | * |
| 213 | * @return the width of the screen. |
| 214 | * |
| 215 | * @throws Exception |
| 216 | */ |
| 217 | int width() throws Exception; |
| 218 | |
| 219 | /** |
| 220 | * Return the actual height of the screen. Some screens can change their |
| 221 | * size and this method must return the actual height. |
| 222 | * |
| 223 | * @return the height of the screen. |
| 224 | * |
| 225 | * @throws Exception |
| 226 | */ |
| 227 | int height() throws Exception; |
| 228 | |
| 229 | /** |
| 230 | * Return the current cursor position. |
| 231 | * |
| 232 | * The position is returned as an array of 2 elements. The first element is |
| 233 | * the x position and the second elements is the y position. Both are zero |
| 234 | * based. |
| 235 | * |
| 236 | * @return the current position or null if not possible. |
| 237 | * |
| 238 | * @throws Exception |
| 239 | */ |
| 240 | int[] getPosition() throws Exception; |
| 241 | |
| 242 | /** |
| 243 | * Position the cursor on the screen. Positioning starts at 0,0 and the |
| 244 | * maxium value is given by {@link #width()}, {@link #height()}. The visible |
| 245 | * cursor is moved to this position and text insertion will continue from |
| 246 | * that position. |
| 247 | * |
| 248 | * @param x |
| 249 | * The x position, must be from 0-width |
| 250 | * @param y |
| 251 | * The y position, must be from 0-height |
| 252 | * @throws IllegalArgumenException |
| 253 | * when x or y is not in range |
| 254 | * @throws Exception |
| 255 | */ |
| 256 | boolean position(int x, int y) throws Exception; |
| 257 | |
| 258 | /** |
| 259 | * Set the attributes of the text to outputed. This method |
| 260 | * must reset all current attributes. That is, attributes |
| 261 | * are not inherited from the current position. |
| 262 | * |
| 263 | * @param foreground The foreground color |
| 264 | * @param background The background color (around the character) |
| 265 | * @param attr A number of attributes. |
| 266 | */ |
| 267 | boolean attributes(Color foreground, Color background, Attribute... attr); |
| 268 | } |