lesscss-java/src/main/java/org/lesscss/LessCompiler.java at master · schuth/lesscss-java · GitHub

Repository navigation

History

401 lines (362 loc) · 15 KB

Raw

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

249

250

251

252

253

254

255

256

257

258

259

260

261

262

263

264

265

266

267

268

269

270

271

272

273

274

275

276

277

278

279

280

281

282

283

284

285

286

287

288

289

290

291

292

293

294

295

296

297

298

299

300

301

302

303

304

305

306

307

308

309

310

311

312

313

314

315

316

317

318

319

320

321

322

323

324

325

326

327

328

329

330

331

332

333

334

335

336

337

338

339

340

341

342

343

344

345

346

347

348

349

350

351

352

353

354

355

356

357

358

359

360

361

362

363

364

365

366

367

368

369

370

371

372

373

374

375

376

377

378

379

380

381

382

383

384

385

386

387

388

389

390

391

392

393

394

395

396

397

398

399

400

401

* Licensed under the Apache License, Version 2.0 (the "License");

* you may not use this file except in compliance with the License.

* You may obtain a copy of the License at

* http://www.apache.org/licenses/LICENSE-2.0

* Unless required by applicable law or agreed to in writing, software

* distributed under the License is distributed on an "AS IS" BASIS,

* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

* See the License for the specific language governing permissions and

* limitations under the License.

package org.lesscss;

import java.io.File;

import java.io.IOException;

import java.io.InputStreamReader;

import java.net.URL;

import java.util.ArrayList;

import java.util.Collections;

import java.util.List;

import org.apache.commons.io.FileUtils;

import org.lesscss.logging.LessLogger;

import org.lesscss.logging.LessLoggerFactory;

import org.mozilla.javascript.Context;

import org.mozilla.javascript.Function;

import org.mozilla.javascript.JavaScriptException;

import org.mozilla.javascript.Scriptable;

import org.mozilla.javascript.ScriptableObject;

import org.mozilla.javascript.tools.shell.Global;

/**

* The LESS compiler to compile LESS sources to CSS stylesheets.

* <p>

* The compiler uses Rhino (JavaScript implementation written in Java), Envjs

* (simulated browser environment written in JavaScript), and the official LESS

* JavaScript compiler.<br />

* Note that the compiler is not a Java implementation of LESS itself, but rather

* integrates the LESS JavaScript compiler within a Java/JavaScript browser

* environment provided by Rhino and Envjs.

* </p>

* <p>

* The compiler comes bundled with the Envjs and LESS JavaScript, so there is

* no need to include them yourself. But if needed they can be overridden.

* </p>

* <h4>Basic code example:</h4>

* <pre>

* LessCompiler lessCompiler = new LessCompiler();

* String css = lessCompiler.compile("@color: #4D926F; #header { color: @color; }");

* </pre>

* @author Marcel Overdijk

* @see <a href="http://lesscss.org/">LESS - The Dynamic Stylesheet language</a>

* @see <a href="http://www.mozilla.org/rhino/">Rhino - JavaScript for Java</a>

* @see <a href="http://www.envjs.com/">Envjs - Bringing the Browser</a>

public class LessCompiler {

private static final LessLogger logger = LessLoggerFactory.getLogger(LessCompiler.class);

private URL envJs = LessCompiler.class.getClassLoader().getResource("META-INF/env.rhino.js");

private URL lessJs = LessCompiler.class.getClassLoader().getResource("META-INF/less-1.5.1.js");

private URL lesscJs = LessCompiler.class.getClassLoader().getResource("META-INF/lessc.js");

private List<URL> customJs = Collections.emptyList();

private boolean compress = false;

private String encoding = null;

private Scriptable scope;

/**

* Constructs a new <code>LessCompiler</code>.

public LessCompiler() {

}

/**

* Returns the Envjs JavaScript file used by the compiler.

* @return The Envjs JavaScript file used by the compiler.

public URL getEnvJs() {

return envJs;

}

/**

* Sets the Envjs JavaScript file used by the compiler.

* Must be set before {@link #init()} is called.

* @param envJs The Envjs JavaScript file used by the compiler.

public synchronized void setEnvJs(URL envJs) {

if (scope != null) {

throw new IllegalStateException("This method can only be called before init()");

}

this.envJs = envJs;

}

/**

* Returns the LESS JavaScript file used by the compiler.

* COMPILE_STRING

* @return The LESS JavaScript file used by the compiler.

public URL getLessJs() {

return lessJs;

}

/**

* Sets the LESS JavaScript file used by the compiler.

* Must be set before {@link #init()} is called.

* @param lessJs LESS JavaScript file used by the compiler.

public synchronized void setLessJs(URL lessJs) {

if (scope != null) {

throw new IllegalStateException("This method can only be called before init()");

}

this.lessJs = lessJs;

}

/**

* Returns the custom JavaScript files used by the compiler.

* @return The custom JavaScript files used by the compiler.

public List<URL> getCustomJs() {

return Collections.unmodifiableList(customJs);

}

/**

* Sets a single custom JavaScript file used by the compiler.

* Must be set before {@link #init()} is called.

* @param customJs A single custom JavaScript file used by the compiler.

public synchronized void setCustomJs(URL customJs) {

if (scope != null) {

throw new IllegalStateException("This method can only be called before init()");

}

this.customJs = Collections.singletonList(customJs);

}

/**

* Sets the custom JavaScript files used by the compiler.

* Must be set before {@link #init()} is called.

* @param customJs The custom JavaScript files used by the compiler.

public synchronized void setCustomJs(List<URL> customJs) {

if (scope != null) {

throw new IllegalStateException("This method can only be called before init()");

}

// copy the list so there's no way for anyone else who holds a reference to the list to modify it

this.customJs = new ArrayList<URL>(customJs);

}

/**

* Returns whether the compiler will compress the CSS.

* @return Whether the compiler will compress the CSS.

public boolean isCompress() {

return compress;

}

/**

* Sets the compiler to compress the CSS.

* Must be set before {@link #init()} is called.

* @param compress If <code>true</code>, sets the compiler to compress the CSS.

public synchronized void setCompress(boolean compress) {

if (scope != null) {

throw new IllegalStateException("This method can only be called before init()");

}

this.compress = compress;

}

/**

* Returns the character encoding used by the compiler when writing the output <code>File</code>.

* @return The character encoding used by the compiler when writing the output <code>File</code>.

public String getEncoding() {

return encoding;

}

/**

* Sets the character encoding used by the compiler when writing the output <code>File</code>.

* If not set the platform default will be used.

* Must be set before {@link #init()} is called.

* @param encoding character encoding used by the compiler when writing the output <code>File</code>.

public synchronized void setEncoding(String encoding) {

if (scope != null) {

throw new IllegalStateException("This method can only be called before init()");

}

this.encoding = encoding;

}

/**

* Initializes this <code>LessCompiler</code>.

* <p>

* It is not needed to call this method manually, as it is called implicitly by the compile methods if needed.

* </p>

public synchronized void init() {

long start = System.currentTimeMillis();

try {

Context cx = Context.enter();

cx.setOptimizationLevel(-1);

cx.setLanguageVersion(Context.VERSION_1_7);

Global global = new Global();

global.init(cx);

scope = cx.initStandardObjects(global);

scope.put("logger", scope, Context.toObject(logger, scope));

List<URL> jsUrls = new ArrayList<URL>();

jsUrls.add(envJs);

jsUrls.add(lessJs);

jsUrls.add(lesscJs);

jsUrls.addAll( customJs );

for(URL url : jsUrls) {

InputStreamReader inputStreamReader = new InputStreamReader(url.openConnection().getInputStream());

try{

cx.evaluateReader(scope, inputStreamReader, url.toString(), 1, null);

}finally{

inputStreamReader.close();

}

catch (Exception e) {

String message = "Failed to initialize LESS compiler.";

logger.error(message, e);

throw new IllegalStateException(message, e);

}finally{

Context.exit();

}

if (logger.isDebugEnabled()) {

logger.debug("Finished initialization of LESS compiler in %,d ms.%n", System.currentTimeMillis() - start);

}

/**

* Compiles the LESS input <code>String</code> to CSS.

* @param input The LESS input <code>String</code> to compile.

* @return The CSS.

public String compile(String input) throws LessException {

return compile( input, "<inline>");

}

/**

* Compiles the LESS input <code>String</code> to CSS, but specifies the source name <code>String</code>.

* @param input The LESS input <code>String</code> to compile

* @param name The source's name <code>String</code> to provide better error messages.

* @return the CSS.

* @throws LessException any error encountered by the compiler

public String compile(String input, String name) throws LessException {

synchronized(this){

if (scope == null) {

init();

}

long start = System.currentTimeMillis();

try {

Context cx = Context.enter();

Function lessc = (Function)scope.get("lessc", scope);

Object result = lessc.call( cx, scope, null, new Object[] {name, input, compress});

if (logger.isDebugEnabled()) {

logger.debug("Finished compilation of LESS source in %,d ms.", System.currentTimeMillis() - start );

}

return result.toString();

}

catch (Exception e) {

if (e instanceof JavaScriptException) {

Scriptable value = (Scriptable)((JavaScriptException)e).getValue();

if (value != null ) {

StringBuilder message = new StringBuilder();

if( ScriptableObject.hasProperty(value, "filename") ) {

message.append( ScriptableObject.getProperty(value, "filename").toString() );

}

if( ScriptableObject.hasProperty(value, "line") ) {

message.append( "@(" );

message.append( ScriptableObject.getProperty(value, "line").toString() );

message.append( "," );

message.append( ScriptableObject.getProperty(value, "column").toString() );

message.append( ")" );

}

if( ScriptableObject.hasProperty(value, "message") ) {

if( message.length() > 0 ) message.append(": ");

message.append( ScriptableObject.getProperty(value, "message").toString() );

}

if( ScriptableObject.hasProperty(value, "extract") ) {

List<String> lines = (List<String>) ScriptableObject.getProperty(value, "extract");

for( String line : lines ) {

if( line != null ) {

message.append("\n");

message.append( line );

}

throw new LessException(message.toString(), e);

}

throw new LessException(e);

}finally{

Context.exit();

}

/**

* Compiles the LESS input <code>File</code> to CSS.

* @param input The LESS input <code>File</code> to compile.

* @return The CSS.

* @throws IOException If the LESS file cannot be read.

public String compile(File input) throws IOException, LessException {

LessSource lessSource = new LessSource(new FileResource(input));

return compile(lessSource);

}

/**

* Compiles the LESS input <code>File</code> to CSS and writes it to the specified output <code>File</code>.

* @param input The LESS input <code>File</code> to compile.

* @param output The output <code>File</code> to write the CSS to.

* @throws IOException If the LESS file cannot be read or the output file cannot be written.

public void compile(File input, File output) throws IOException, LessException {

this.compile(input, output, true);

}

/**

* Compiles the LESS input <code>File</code> to CSS and writes it to the specified output <code>File</code>.

* @param input The LESS input <code>File</code> to compile.

* @param output The output <code>File</code> to write the CSS to.

* @param force 'false' to only compile the LESS input file in case the LESS source has been modified (including imports) or the output file does not exists.

* @throws IOException If the LESS file cannot be read or the output file cannot be written.

public void compile(File input, File output, boolean force) throws IOException, LessException {

LessSource lessSource = new LessSource(new FileResource(input));

compile(lessSource, output, force);

}

/**

* Compiles the input <code>LessSource</code> to CSS.

* @param input The input <code>LessSource</code> to compile.

* @return The CSS.

public String compile(LessSource input) throws LessException {

return compile(input.getNormalizedContent(), input.getName());

}

/**

* Compiles the input <code>LessSource</code> to CSS and writes it to the specified output <code>File</code>.

* @param input The input <code>LessSource</code> to compile.

* @param output The output <code>File</code> to write the CSS to.

* @throws IOException If the LESS file cannot be read or the output file cannot be written.

public void compile(LessSource input, File output) throws IOException, LessException {

compile(input, output, true);

}

/**

* Compiles the input <code>LessSource</code> to CSS and writes it to the specified output <code>File</code>.

* @param input The input <code>LessSource</code> to compile.

* @param output The output <code>File</code> to write the CSS to.

* @param force 'false' to only compile the input <code>LessSource</code> in case the LESS source has been modified (including imports) or the output file does not exists.

* @throws IOException If the LESS file cannot be read or the output file cannot be written.

public void compile(LessSource input, File output, boolean force) throws IOException, LessException {

if (force || !output.exists() || output.lastModified() < input.getLastModifiedIncludingImports()) {

String data = compile(input);

FileUtils.writeStringToFile(output, data, encoding);

}

lesscss-java/src/main/java/org/lesscss/LessCompiler.java at master · schuth/lesscss-java · GitHub

Repository navigation

Expand file tree

Breadcrumbs

LessCompiler.java

Latest commit

History

Breadcrumbs

LessCompiler.java

File metadata and controls