Java tutorial
/* * Copyright 2011 PrimeFaces Extensions. * * 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. * * $Id: ClosureCompilerOptimizer.java 513 2011-12-01 18:58:10Z ovaraksin@googlemail.com $ */ package org.primefaces.extensions.optimizerplugin; import java.io.File; import java.nio.charset.Charset; import java.util.ArrayList; import java.util.List; import java.util.logging.Level; import org.apache.maven.plugin.MojoExecutionException; import org.apache.maven.plugin.logging.Log; import org.codehaus.plexus.util.FileUtils; import org.codehaus.plexus.util.StringUtils; import com.google.common.io.Files; import com.google.javascript.jscomp.CompilationLevel; import com.google.javascript.jscomp.Compiler; import com.google.javascript.jscomp.CompilerOptions; import com.google.javascript.jscomp.JSError; import com.google.javascript.jscomp.JSSourceFile; import com.google.javascript.jscomp.Result; import com.google.javascript.jscomp.WarningLevel; /** * Class for Google Closure Compiler doing JavaScript optimization. * * @author Oleg Varaksin / last modified by $Author: ovaraksin@googlemail.com $ * @version $Revision: 513 $ * @since 0.1 */ public class ClosureCompilerOptimizer extends AbstractOptimizer { // Note: empty externs, probably CommandLineRunner.getDefaultExterns() would be better private static final List<JSSourceFile> EXTERNS_EMPTY = new ArrayList<JSSourceFile>(); private static final String OPTIMIZED_FILE_EXTENSION = ".optjs"; @Override public void optimize(final ResourcesSetAdapter rsa, final Log log) throws MojoExecutionException { CompilationLevel compLevel = rsa.getCompilationLevel(); CompilerOptions options = new CompilerOptions(); compLevel.setOptionsForCompilationLevel(options); WarningLevel warnLevel = rsa.getWarningLevel(); warnLevel.setOptionsForWarningLevel(options); com.google.javascript.jscomp.Compiler.setLoggingLevel(Level.WARNING); try { Charset cset = Charset.forName(rsa.getEncoding()); if (rsa.getAggregation() == null) { // no aggregation for (File file : rsa.getFiles()) { log.info("Optimize JS file " + file.getName() + " ..."); addToOriginalSize(file); JSSourceFile jsSourceFile = JSSourceFile.fromFile(file, cset); List<JSSourceFile> interns = new ArrayList<JSSourceFile>(); interns.add(jsSourceFile); // compile Compiler compiler = compile(log, interns, options, rsa.isFailOnWarning()); // generate output String path = file.getCanonicalPath(); if (StringUtils.isNotBlank(rsa.getSuffix())) { // write compiled content into the new file File outputFile = getFileWithSuffix(path, rsa.getSuffix()); Files.write(compiler.toSource(), outputFile, cset); // statistic addToOptimizedSize(outputFile); } else { // path of temp. file String pathOptimized = FileUtils.removeExtension(path) + OPTIMIZED_FILE_EXTENSION; // create a new temp. file File outputFile = new File(pathOptimized); Files.touch(outputFile); // write compiled content into the new file and rename it (overwrite the original file) Files.write(compiler.toSource(), outputFile, cset); FileUtils.rename(outputFile, file); // statistic addToOptimizedSize(file); } } } else if (rsa.getAggregation().getOutputFile() != null) { // aggregation to one output file File outputFile; if (!rsa.getAggregation().isWithoutCompress()) { // with compressing before aggregation List<JSSourceFile> interns = new ArrayList<JSSourceFile>(); for (File file : rsa.getFiles()) { log.info("Optimize JS file " + file.getName() + " ..."); addToOriginalSize(file); interns.add(JSSourceFile.fromFile(file, cset)); } // compile Compiler compiler = compile(log, interns, options, rsa.isFailOnWarning()); int filesCount = rsa.getFiles().size(); if (rsa.getAggregation().getPrependedFile() != null) { filesCount++; } if (filesCount > 1) { log.info("Aggregation is running ..."); } // get right output file outputFile = getOutputFile(rsa); long sizeBefore = outputFile.length(); if (rsa.getAggregation().getPrependedFile() != null) { // write / append to be prepended file into / to the output file prependFile(rsa.getAggregation().getPrependedFile(), outputFile, cset, rsa.getEncoding()); } // write / append compiled content into / to the output file Files.append(compiler.toSource(), outputFile, cset); // statistic addToOptimizedSize(outputFile.length() - sizeBefore); if (filesCount > 1) { log.info(filesCount + " files were successfully aggregated."); } } else { // only aggregation without compressing outputFile = aggregateFiles(rsa, cset, log); } // delete single files if necessary deleteFilesIfNecessary(rsa, log); // rename aggregated file if necessary renameOutputFileIfNecessary(rsa, outputFile); } else { // should not happen log.error("Wrong plugin's internal state."); } } catch (Exception e) { throw new MojoExecutionException("Resources optimization failure: " + e.getLocalizedMessage(), e); } } protected Compiler compile(final Log log, final List<JSSourceFile> interns, final CompilerOptions options, final boolean failOnWarning) throws MojoExecutionException { // compile com.google.javascript.jscomp.Compiler compiler = new Compiler(); Result result = compiler.compile(EXTERNS_EMPTY, interns, options); // evaluate result evalResult(result, log, failOnWarning); return compiler; } protected void evalResult(final Result result, final Log log, final boolean failOnWarning) throws MojoExecutionException { if (result.warnings != null) { for (JSError warning : result.warnings) { log.warn(warning.toString()); } } if (result.warnings != null && result.warnings.length > 0 && failOnWarning) { throw new MojoExecutionException("Resources optimization failure. Please fix warnings and try again."); } if (result.errors != null) { for (JSError error : result.errors) { log.error(error.toString()); } } if (result.errors != null && result.errors.length > 0) { throw new MojoExecutionException("Resources optimization failure. Please fix errors and try again."); } if (!result.success) { throw new MojoExecutionException("Resources optimization failure. Please fix errors and try again."); } } }