1 # [Google Closure Compiler](https://developers.google.com/closure/compiler/) 2 3 The [Closure Compiler](https://developers.google.com/closure/compiler/) is a tool for making JavaScript download and run faster. It is a true compiler for JavaScript. Instead of compiling from a source language to machine code, it compiles from JavaScript to better JavaScript. It parses your JavaScript, analyzes it, removes dead code and rewrites and minimizes what's left. It also checks syntax, variable references, and types, and warns about common JavaScript pitfalls. 4 5 ## Getting Started 6 * [Download the latest version](http://dl.google.com/closure-compiler/compiler-latest.zip) 7 * See the [Google Developers Site](https://developers.google.com/closure/compiler/docs/gettingstarted_app) for documentation including instructions for running the compiler from the command line. 8 9 ## Options for Getting Help 10 1. Post in the [Closure Compiler Discuss Group] (https://groups.google.com/forum/#!forum/closure-compiler-discuss) 11 2. Ask a question on [Stack Overflow](http://stackoverflow.com/questions/tagged/google-closure-compiler) 12 3. Consult the [FAQ](https://github.com/google/closure-compiler/wiki/FAQ) 13 14 ## Building it Yourself 15 16 Note: The Closure Compiler requires [Java 7 or higher](http://www.java.com/). 17 18 ### Using [Ant](http://ant.apache.org/) 19 20 1. Download the [Ant build tool](http://ant.apache.org/bindownload.cgi). 21 22 2. At the root of the source tree, there is an Ant file named ```build.xml```. 23 To use it, navigate to the same directory and type the command 24 25 ``` 26 ant jar 27 ``` 28 29 This will produce a jar file called ```build/compiler.jar```. 30 31 ### Using [Eclipse](http://www.eclipse.org/) 32 33 1. Download and open the [Eclipse IDE](http://www.eclipse.org/). 34 2. Navigate to ```File > New > Project ...``` and create a Java Projet. Give 35 the project a name. 36 3. Select ```Create project from existing source``` and choose the root of the 37 checked-out source tree as the existing directory. 38 3. Navigate to the ```build.xml``` file. You will see all the build rules in 39 the Outline pane. Run the ```jar``` rule to build the compiler in 40 ```build/compiler.jar```. 41 42 ## Running 43 44 On the command line, type 45 46 ``` 47 java -jar compiler.jar 48 ``` 49 50 This starts the compiler in interactive mode. Type 51 52 ```javascript 53 var x = 17 + 25; 54 ``` 55 56 then hit "Enter", then hit "Ctrl-Z" (on Windows) or "Ctrl-D" (on Mac or Linux) 57 and "Enter" again. The Compiler will respond: 58 59 ```javascript 60 var x=42; 61 ``` 62 63 The Closure Compiler has many options for reading input from a file, writing 64 output to a file, checking your code, and running optimizations. To learn more, 65 type 66 67 ``` 68 java -jar compiler.jar --help 69 ``` 70 71 More detailed information about running the Closure Compiler is available in the 72 [documentation](http://code.google.com/closure/compiler/docs/gettingstarted_app.html). 73 74 ## Compiling Multiple Scripts 75 76 If you have multiple scripts, you should compile them all together with one 77 compile command. 78 79 ```bash 80 java -jar compiler.jar --js_output_file=out.js in1.js in2.js in3.js ... 81 ``` 82 83 You can also use minimatch-style globs. 84 85 ```bash 86 # Recursively include all js files in subdirs 87 java -jar compiler.jar --js_output_file=out.js 'src/**.js' 88 89 # Recursively include all js files in subdirs, exclusing test files. 90 # Use single-quotes, so that bash doesn't try to expand the '!' 91 java -jar compiler.jar --js_output_file=out.js 'src/**.js' '!**_test.js' 92 ``` 93 94 The Closure Compiler will concatenate the files in the order they're passed at 95 the command line. 96 97 If you're using globs or many files, you may start to run into 98 problems with managing dependencies between scripts. In this case, you should 99 use the [Closure Library](https://developers.google.com/closure/library/). It 100 contains functions for enforcing dependencies between scripts, and Closure Compiler 101 will re-order the inputs automatically. 102 103 ## How to Contribute 104 ### Reporting a bug 105 1. First make sure that it is really a bug and not simply the way that Closure Compiler works (especially true for ADVANCED_OPTIMIZATIONS). 106 * Check the [official documentation](https://developers.google.com/closure/compiler/) 107 * Consult the [FAQ](https://github.com/google/closure-compiler/wiki/FAQ) 108 * Search on [Stack Overflow](http://stackoverflow.com/questions/tagged/google-closure-compiler) and in the [Closure Compiler Discuss Group](https://groups.google.com/forum/#!forum/closure-compiler-discuss) 109 2. If you still think you have found a bug, make sure someone hasn't already reported it. See the list of [known issues](https://github.com/google/closure-compiler/issues). 110 3. If it hasn't been reported yet, post a new issue. Make sure to add enough detail so that the bug can be recreated. The smaller the reproduction code, the better. 111 112 ### Suggesting a Feature 113 1. Consult the [FAQ](https://github.com/google/closure-compiler/wiki/FAQ) to make sure that the behaviour you would like isn't specifically excluded (such as string inlining). 114 2. Make sure someone hasn't requested the same thing. See the list of [known issues](https://github.com/google/closure-compiler/issues). 115 3. Read up on [what type of feature requests are accepted](https://github.com/google/closure-compiler/wiki/FAQ#how-do-i-submit-a-feature-request-for-a-new-type-of-optimization). 116 4. Submit your reqest as an issue. 117 118 ### Submitting patches 119 1. All contributors must sign a contributor license agreement. See the [CONTRIBUTORS](https://raw.githubusercontent.com/google/closure-compiler/master/CONTRIBUTORS) file for details. 120 2. To make sure your changes are of the type that will be accepted, ask about your patch on the [Closure Compiler Discuss Group](https://groups.google.com/forum/#!forum/closure-compiler-discuss) 121 3. Fork the repository. 122 4. Make your changes. 123 5. Submit a pull request for your changes. A project developer will review your work and then merge your request into the project. 124 125 ## Closure Compiler License 126 127 Copyright 2009 The Closure Compiler Authors. 128 129 Licensed under the Apache License, Version 2.0 (the "License"); 130 you may not use this file except in compliance with the License. 131 You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0. 132 133 Unless required by applicable law or agreed to in writing, software 134 distributed under the License is distributed on an "AS IS" BASIS, 135 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 136 See the License for the specific language governing permissions and 137 limitations under the License. 138 139 ## Dependency Licenses 140 141 ### Rhino 142 143 Two copies of Rhino exist in this repository: 144 145 <table> 146 <tr> 147 <td>Code Path</td> 148 <td><code>lib/rhino</code></td> 149 </tr> 150 151 <tr> 152 <td>URL</td> 153 <td>http://www.mozilla.org/rhino</td> 154 </tr> 155 156 <tr> 157 <td>Version</td> 158 <td>Trunk</td> 159 </tr> 160 161 <tr> 162 <td>License</td> 163 <td>Netscape Public License and MPL / GPL dual license</td> 164 </tr> 165 166 <tr> 167 <td>Description</td> 168 <td>Mozilla Rhino is an implementation of JavaScript for the JVM.</td> 169 </tr> 170 171 <tr> 172 <td>Local Modifications</td> 173 <td>Minor changes to parsing JSDoc that usually get pushed 174 up-stream to Rhino trunk.</td> 175 </tr> 176 </table> 177 178 <table> 179 <tr> 180 <td>Code Path</td> 181 <td> 182 <code>src/com/google/javascript/rhino</code>, <code>test/com/google/javascript/rhino</code> 183 </td> 184 </tr> 185 186 <tr> 187 <td>URL</td> 188 <td>http://www.mozilla.org/rhino</td> 189 </tr> 190 191 <tr> 192 <td>Version</td> 193 <td>1.5R3, with heavy modifications</td> 194 </tr> 195 196 <tr> 197 <td>License</td> 198 <td>Netscape Public License and MPL / GPL dual license</td> 199 </tr> 200 201 <tr> 202 <td>Description</td> 203 <td>A partial copy of Mozilla Rhino. Mozilla Rhino is an 204 implementation of JavaScript for the JVM. The JavaScript parser and 205 the parse tree data structures were extracted and modified 206 significantly for use by Google's JavaScript compiler.</td> 207 </tr> 208 209 <tr> 210 <td>Local Modifications</td> 211 <td>The packages have been renamespaced. All code not 212 relevant to parsing has been removed. A JsDoc parser and static typing 213 system have been added.</td> 214 </tr> 215 </table> 216 217 ### Args4j 218 219 <table> 220 <tr> 221 <td>Code Path</td> 222 <td><code>lib/args4j.jar</code></td> 223 </tr> 224 225 <tr> 226 <td>URL</td> 227 <td>https://args4j.dev.java.net/</td> 228 </tr> 229 230 <tr> 231 <td>Version</td> 232 <td>2.0.26</td> 233 </tr> 234 235 <tr> 236 <td>License</td> 237 <td>MIT</td> 238 </tr> 239 240 <tr> 241 <td>Description</td> 242 <td>args4j is a small Java class library that makes it easy to parse command line 243 options/arguments in your CUI application.</td> 244 </tr> 245 246 <tr> 247 <td>Local Modifications</td> 248 <td>None</td> 249 </tr> 250 </table> 251 252 ### Guava Libraries 253 254 <table> 255 <tr> 256 <td>Code Path</td> 257 <td><code>lib/guava.jar</code></td> 258 </tr> 259 260 <tr> 261 <td>URL</td> 262 <td>http://code.google.com/p/guava-libraries/</td> 263 </tr> 264 265 <tr> 266 <td>Version</td> 267 <td>17.0</td> 268 </tr> 269 270 <tr> 271 <td>License</td> 272 <td>Apache License 2.0</td> 273 </tr> 274 275 <tr> 276 <td>Description</td> 277 <td>Google's core Java libraries.</td> 278 </tr> 279 280 <tr> 281 <td>Local Modifications</td> 282 <td>None</td> 283 </tr> 284 </table> 285 286 ### JSR 305 287 288 <table> 289 <tr> 290 <td>Code Path</td> 291 <td><code>lib/jsr305.jar</code></td> 292 </tr> 293 294 <tr> 295 <td>URL</td> 296 <td>http://code.google.com/p/jsr-305/</td> 297 </tr> 298 299 <tr> 300 <td>Version</td> 301 <td>svn revision 47</td> 302 </tr> 303 304 <tr> 305 <td>License</td> 306 <td>BSD License</td> 307 </tr> 308 309 <tr> 310 <td>Description</td> 311 <td>Annotations for software defect detection.</td> 312 </tr> 313 314 <tr> 315 <td>Local Modifications</td> 316 <td>None</td> 317 </tr> 318 </table> 319 320 ### Jar Jar Links 321 322 <table> 323 <tr> 324 <td>Code Path</td> 325 <td><code>lib/jarjar.jar</code></td> 326 </tr> 327 328 <tr> 329 <td>URL</td> 330 <td>http://jarjar.googlecode.com/</td> 331 </tr> 332 333 <tr> 334 <td>Version</td> 335 <td>1.1</td> 336 </tr> 337 338 <tr> 339 <td>License</td> 340 <td>Apache License 2.0</td> 341 </tr> 342 343 <tr> 344 <td>Description</td> 345 <td>A utility for repackaging Java libraries.</td> 346 </tr> 347 348 <tr> 349 <td>Local Modifications</td> 350 <td>None</td> 351 </tr> 352 </table> 353 354 ### JUnit 355 356 <table> 357 <tr> 358 <td>Code Path</td> 359 <td><code>lib/junit.jar</code></td> 360 </tr> 361 362 <tr> 363 <td>URL</td> 364 <td>http://sourceforge.net/projects/junit/</td> 365 </tr> 366 367 <tr> 368 <td>Version</td> 369 <td>4.11</td> 370 </tr> 371 372 <tr> 373 <td>License</td> 374 <td>Common Public License 1.0</td> 375 </tr> 376 377 <tr> 378 <td>Description</td> 379 <td>A framework for writing and running automated tests in Java.</td> 380 </tr> 381 382 <tr> 383 <td>Local Modifications</td> 384 <td>None</td> 385 </tr> 386 </table> 387 388 ### Protocol Buffers 389 390 <table> 391 <tr> 392 <td>Code Path</td> 393 <td><code>lib/protobuf-java.jar</code></td> 394 </tr> 395 396 <tr> 397 <td>URL</td> 398 <td>http://code.google.com/p/protobuf/</td> 399 </tr> 400 401 <tr> 402 <td>Version</td> 403 <td>2.5.0</td> 404 </tr> 405 406 <tr> 407 <td>License</td> 408 <td>New BSD License</td> 409 </tr> 410 411 <tr> 412 <td>Description</td> 413 <td>Supporting libraries for protocol buffers, 414 an encoding of structured data.</td> 415 </tr> 416 417 <tr> 418 <td>Local Modifications</td> 419 <td>None</td> 420 </tr> 421 </table> 422 423 ### Ant 424 425 <table> 426 <tr> 427 <td>Code Path</td> 428 <td> 429 <code>lib/ant.jar</code>, <code>lib/ant-launcher.jar</code> 430 </td> 431 </tr> 432 433 <tr> 434 <td>URL</td> 435 <td>http://ant.apache.org/bindownload.cgi</td> 436 </tr> 437 438 <tr> 439 <td>Version</td> 440 <td>1.8.1</td> 441 </tr> 442 443 <tr> 444 <td>License</td> 445 <td>Apache License 2.0</td> 446 </tr> 447 448 <tr> 449 <td>Description</td> 450 <td>Ant is a Java based build tool. In theory it is kind of like "make" 451 without make's wrinkles and with the full portability of pure java code.</td> 452 </tr> 453 454 <tr> 455 <td>Local Modifications</td> 456 <td>None</td> 457 </tr> 458 </table> 459 460 ### JSON 461 462 <table> 463 <tr> 464 <td>Code Path</td> 465 <td><code>lib/json.jar</code></td> 466 </tr> 467 468 <tr> 469 <td>URL</td> 470 <td>http://json.org/java/index.html</td> 471 </tr> 472 473 <tr> 474 <td>Version</td> 475 <td>JSON version 20090211</td> 476 </tr> 477 478 <tr> 479 <td>License</td> 480 <td>MIT license</td> 481 </tr> 482 483 <tr> 484 <td>Description</td> 485 <td>JSON is a set of java files for use in transmitting data in JSON format.</td> 486 </tr> 487 488 <tr> 489 <td>Local Modifications</td> 490 <td>None</td> 491 </tr> 492 </table> 493 494 ### Mockito 495 496 <table> 497 <tr> 498 <td>Code Path</td> 499 <td><code>lib/mockito-core.jar</code></td> 500 </tr> 501 502 <tr> 503 <td>URL</td> 504 <td>https://code.google.com/p/mockito</td> 505 </tr> 506 507 <tr> 508 <td>Version</td> 509 <td>1.9.5</td> 510 </tr> 511 512 <tr> 513 <td>License</td> 514 <td>MIT license</td> 515 </tr> 516 517 <tr> 518 <td>Description</td> 519 <td>Mockito is an open source testing framework for Java. The framework allows the 520 creation of Test Double objects (called "Mock Objects") in automated unit tests 521 for the purpose of Test-driven Development (TDD) or Behavior Driven Development 522 (BDD).</td> 523 </tr> 524 525 <tr> 526 <td>Local Modifications</td> 527 <td>None</td> 528 </tr> 529 </table> 530 531 ### Objenesis 532 533 <table> 534 <tr> 535 <td>Code Path</td> 536 <td><code>lib/objenesis.jar</code></td> 537 </tr> 538 539 <tr> 540 <td>URL</td> 541 <td>http://objenesis.org</td> 542 </tr> 543 544 <tr> 545 <td>Version</td> 546 <td>1.2</td> 547 </tr> 548 549 <tr> 550 <td>License</td> 551 <td>Apache 2.0 license</td> 552 </tr> 553 554 <tr> 555 <td>Description</td> 556 <td>Depended by lib/mockito-core.jar, not used directly.</td> 557 </tr> 558 559 <tr> 560 <td>Local Modifications</td> 561 <td>None</td> 562 </tr> 563 </table> 564