1 /*
2 * Copyright 2009-2022 the original author or authors.
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 package com.googlecode.htmlcompressor.compressor;
17
18 import com.yahoo.platform.yui.compressor.JavaScriptCompressor;
19
20 import java.io.IOException;
21 import java.io.StringReader;
22 import java.io.StringWriter;
23
24 import org.mozilla.javascript.ErrorReporter;
25 import org.mozilla.javascript.EvaluatorException;
26 import org.slf4j.Logger;
27 import org.slf4j.LoggerFactory;
28
29 /**
30 * Basic JavaScript compressor implementation using <a href="http://developer.yahoo.com/yui/compressor/">Yahoo YUI
31 * Compressor</a> that could be used by {@link HtmlCompressor} for inline JavaScript compression.
32 *
33 * @author <a href="mailto:serg472@gmail.com">Sergiy Kovalchuk</a>
34 *
35 * @see HtmlCompressor#setJavaScriptCompressor(Compressor)
36 * @see <a href="http://developer.yahoo.com/yui/compressor/">Yahoo YUI Compressor</a>
37 */
38 public class YuiJavaScriptCompressor implements Compressor {
39
40 /** The Constant logger. */
41 private static final Logger logger = LoggerFactory.getLogger(YuiJavaScriptCompressor.class);
42
43 // YUICompressor default settings
44
45 /** The no munge. */
46 private boolean noMunge;
47
48 /** The preserve all semi colons. */
49 private boolean preserveAllSemiColons;
50
51 /** The disable optimizations. */
52 private boolean disableOptimizations;
53
54 /** The line break. */
55 private int lineBreak = -1;
56
57 /** The error reporter. */
58 private ErrorReporter errorReporter = new DefaultErrorReporter();
59
60 @Override
61 public String compress(String source) {
62
63 StringWriter result = new StringWriter();
64 try {
65 JavaScriptCompressor compressor = new JavaScriptCompressor(new StringReader(source), errorReporter);
66 compressor.compress(result, lineBreak, !noMunge, false, preserveAllSemiColons, disableOptimizations);
67 } catch (IOException e) {
68 result.write(source);
69 logger.error("", e);
70 }
71 return result.toString();
72
73 }
74
75 /**
76 * Default <code>ErrorReporter</code> implementation that uses <code>System.err</code> stream for error reporting.
77 * Used by YUI Compressor to log errors during JavaScript compression.
78 *
79 * @author <a href="mailto:serg472@gmail.com">Sergiy Kovalchuk</a>
80 *
81 * @see <a href="http://developer.yahoo.com/yui/compressor/">Yahoo YUI Compressor</a>
82 * @see <a href="http://www.mozilla.org/rhino/apidocs/org/mozilla/javascript/ErrorReporter.html">ErrorReporter
83 * Interface</a>
84 */
85 public static class DefaultErrorReporter implements ErrorReporter {
86
87 @Override
88 public void warning(String message, String sourceName, int line, String lineSource, int lineOffset) {
89 if (line < 0) {
90 logger.error("[WARNING] HtmlCompressor: '{}' during JavaScript compression", message);
91 } else {
92 logger.error("[WARNING] HtmlCompressor: '{}' at line [{}:{}] during JavaScript compression {}", message,
93 line, lineOffset, lineSource != null ? ": " + lineSource : "");
94 }
95 }
96
97 @Override
98 public void error(String message, String sourceName, int line, String lineSource, int lineOffset) {
99 if (line < 0) {
100 logger.error("[ERROR] HtmlCompressor: '{}' during JavaScript compression", message);
101 } else {
102 logger.error("[ERROR] HtmlCompressor: '{}' at line [{}:{}] during JavaScript compression {}", message,
103 line, lineOffset, lineSource != null ? ": " + lineSource : "");
104 }
105 }
106
107 @Override
108 public EvaluatorException runtimeError(String message, String sourceName, int line, String lineSource,
109 int lineOffset) {
110 error(message, sourceName, line, lineSource, lineOffset);
111 return new EvaluatorException(message);
112 }
113 }
114
115 /**
116 * Returns <code>true</code> if Yahoo YUI Compressor will only minify javascript without obfuscating local symbols.
117 * This corresponds to <code>--nomunge</code> command line option.
118 *
119 * @return <code>nomunge</code> parameter value used for JavaScript compression.
120 *
121 * @see <a href="http://developer.yahoo.com/yui/compressor/">Yahoo YUI Compressor</a>
122 */
123 public boolean isNoMunge() {
124 return noMunge;
125 }
126
127 /**
128 * Tells Yahoo YUI Compressor to only minify javascript without obfuscating local symbols. This corresponds to
129 * <code>--nomunge</code> command line option. This option has effect only if JavaScript compression is enabled.
130 * Default is <code>false</code>.
131 *
132 * @param noMunge
133 * set <code>true</code> to enable <code>nomunge</code> mode
134 *
135 * @see <a href="http://developer.yahoo.com/yui/compressor/">Yahoo YUI Compressor</a>
136 */
137 public void setNoMunge(boolean noMunge) {
138 this.noMunge = noMunge;
139 }
140
141 /**
142 * Returns <code>true</code> if Yahoo YUI Compressor will preserve unnecessary semicolons during JavaScript
143 * compression. This corresponds to <code>--preserve-semi</code> command line option.
144 *
145 * @return <code>preserve-semi</code> parameter value used for JavaScript compression.
146 *
147 * @see <a href="http://developer.yahoo.com/yui/compressor/">Yahoo YUI Compressor</a>
148 */
149 public boolean isPreserveAllSemiColons() {
150 return preserveAllSemiColons;
151 }
152
153 /**
154 * Tells Yahoo YUI Compressor to preserve unnecessary semicolons during JavaScript compression. This corresponds to
155 * <code>--preserve-semi</code> command line option. This option has effect only if JavaScript compression is
156 * enabled. Default is <code>false</code>.
157 *
158 * @param preserveAllSemiColons
159 * set <code>true</code> to enable <code>preserve-semi</code> mode
160 *
161 * @see <a href="http://developer.yahoo.com/yui/compressor/">Yahoo YUI Compressor</a>
162 */
163 public void setPreserveAllSemiColons(boolean preserveAllSemiColons) {
164 this.preserveAllSemiColons = preserveAllSemiColons;
165 }
166
167 /**
168 * Returns <code>true</code> if Yahoo YUI Compressor will disable all the built-in micro optimizations during
169 * JavaScript compression. This corresponds to <code>--disable-optimizations</code> command line option.
170 *
171 * @return <code>disable-optimizations</code> parameter value used for JavaScript compression.
172 *
173 * @see <a href="http://developer.yahoo.com/yui/compressor/">Yahoo YUI Compressor</a>
174 */
175 public boolean isDisableOptimizations() {
176 return disableOptimizations;
177 }
178
179 /**
180 * Tells Yahoo YUI Compressor to disable all the built-in micro optimizations during JavaScript compression. This
181 * corresponds to <code>--disable-optimizations</code> command line option. This option has effect only if
182 * JavaScript compression is enabled. Default is <code>false</code>.
183 *
184 * @param disableOptimizations
185 * set <code>true</code> to enable <code>disable-optimizations</code> mode
186 *
187 * @see <a href="http://developer.yahoo.com/yui/compressor/">Yahoo YUI Compressor</a>
188 */
189 public void setDisableOptimizations(boolean disableOptimizations) {
190 this.disableOptimizations = disableOptimizations;
191 }
192
193 /**
194 * Returns number of symbols per line Yahoo YUI Compressor will use during JavaScript compression. This corresponds
195 * to <code>--line-break</code> command line option.
196 *
197 * @return <code>line-break</code> parameter value used for JavaScript compression.
198 *
199 * @see <a href="http://developer.yahoo.com/yui/compressor/">Yahoo YUI Compressor</a>
200 */
201 public int getLineBreak() {
202 return lineBreak;
203 }
204
205 /**
206 * Tells Yahoo YUI Compressor to break lines after the specified number of symbols during JavaScript compression.
207 * This corresponds to <code>--line-break</code> command line option. This option has effect only if JavaScript
208 * compression is enabled. Default is <code>-1</code> to disable line breaks.
209 *
210 * @param lineBreak
211 * set number of symbols per line
212 *
213 * @see <a href="http://developer.yahoo.com/yui/compressor/">Yahoo YUI Compressor</a>
214 */
215 public void setLineBreak(int lineBreak) {
216 this.lineBreak = lineBreak;
217 }
218
219 /**
220 * Returns <code>ErrorReporter</code> used by YUI Compressor to log error messages during JavasSript compression.
221 *
222 * @return <code>ErrorReporter</code> used by YUI Compressor to log error messages during JavasSript compression
223 *
224 * @see <a href="http://developer.yahoo.com/yui/compressor/">Yahoo YUI Compressor</a>
225 * @see <a href="http://www.mozilla.org/rhino/apidocs/org/mozilla/javascript/ErrorReporter.html">Error Reporter
226 * Interface</a>
227 */
228 public ErrorReporter getErrorReporter() {
229 return errorReporter;
230 }
231
232 /**
233 * Sets <code>ErrorReporter</code> that YUI Compressor will use for reporting errors during JavaScript compression.
234 * If no <code>ErrorReporter</code> was provided {@link YuiJavaScriptCompressor.DefaultErrorReporter} will be used
235 * which reports errors to <code>System.err</code> stream.
236 *
237 * @param errorReporter
238 * <code>ErrorReporter</code> that will be used by YUI Compressor
239 *
240 * @see YuiJavaScriptCompressor.DefaultErrorReporter
241 * @see <a href="http://developer.yahoo.com/yui/compressor/">Yahoo YUI Compressor</a>
242 * @see <a href="http://www.mozilla.org/rhino/apidocs/org/mozilla/javascript/ErrorReporter.html">ErrorReporter
243 * Interface</a>
244 */
245 public void setErrorReporter(ErrorReporter errorReporter) {
246 this.errorReporter = errorReporter;
247 }
248
249 }