Remove closure in favor of a simple JSMin implementation

Closure is a great js-minifier, but js-minification is really
outside the scope of this project.
A simple space/line stripper should be suffcient.

pom.xml

@@ -51,12 +51,6 @@
             <artifactId>commons-lang3</artifactId>
             <version>3.4</version>
         </dependency>
-        <dependency>
-            <groupId>com.google.javascript</groupId>
-            <artifactId>closure-compiler</artifactId>
-            <version>v20151015</version>
-            <optional>true</optional>
-        </dependency>
     </dependencies>
 
     <packaging>jar</packaging>

src/main/java/j2html/tags/InlineStaticResource.java

@@ -14,7 +14,7 @@ public class InlineStaticResource {
         if(fileString != null) {
             switch(format) {
                 case CSS_MIN : return style().with(unsafeHtml(compressCss(fileString)));
-                case JS_MIN  : return script().with(unsafeHtml(compressJs(fileString, path)));
+                case JS_MIN  : return script().with(unsafeHtml(compressJs(fileString)));
                 case CSS     : return style().with(unsafeHtml(fileString));
                 case JS      : return script().with(unsafeHtml(fileString));
                 default      : return errorAlert;
@@ -35,8 +35,8 @@ public class InlineStaticResource {
         return CSSMin.compress(code);
     }
 
-    private static String compressJs(String code, String debugPath) {
+    private static String compressJs(String code) {
-        return JSMin.compressJs(code, debugPath);
+        return JSMin.compressJs(code);
     }
 
 }

src/main/java/j2html/utils/JSMin.java

@@ -1,32 +1,305 @@
 package j2html.utils;
+/*
+ * JSMin.java 2006-02-13
+ *
+ * Copyright (c) 2006 John Reilly (www.inconspicuous.org)
+ *
+ * This work is a translation from C to Java of jsmin.c published by
+ * Douglas Crockford.  Permission is hereby granted to use the Java
+ * version under the same conditions as the jsmin.c on which it is
+ * based.
+ *
+ *
+ *
+ *
+ * jsmin.c 2003-04-21
+ *
+ * Copyright (c) 2002 Douglas Crockford (www.crockford.com)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * The Software shall be used for Good, not Evil.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+// package org.inconspicuous.jsmin;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.io.PushbackInputStream;
 
-import com.google.javascript.jscomp.*;
-import com.google.javascript.jscomp.Compiler;
 
 public class JSMin {
 
-    private JSMin() {}
+    /**
-
+     * Compress a JS-string
-    public static String compressJs(String code, String sourcePath) {
+     *
-        return isPresent("com.google.javascript.jscomp.Compiler") ? compressJsUsingClosureCompiler(code, sourcePath) : code;
+     * @param code the js-code you want to compress
-    }
+     * @return the compressed code
-
+     */
-    private static boolean isPresent(String className) {
+    public static String compressJs(String code) {
+        InputStream inStream = new ByteArrayInputStream(code.getBytes());
+        ByteArrayOutputStream outStream = new ByteArrayOutputStream();
+        JSMin jsmin = new JSMin(inStream, outStream);
         try {
-            Class.forName(className);
+            jsmin.jsmin();
-            return true;
+            return outStream.toString().trim();
-        } catch (Exception e) {
+        } catch (IOException | UnterminatedRegExpLiteralException | UnterminatedCommentException | UnterminatedStringLiteralException e) {
-            return false;
+            e.printStackTrace();
+            return "";
         }
     }
 
-    private static String compressJsUsingClosureCompiler(String code, String sourcePath) {
+    private static final int EOF = -1;
-        com.google.javascript.jscomp.Compiler compiler = new Compiler();
+
-        CompilerOptions options = new CompilerOptions();
+    private PushbackInputStream in;
-        CompilationLevel.SIMPLE_OPTIMIZATIONS.setOptionsForCompilationLevel(options);
+    private OutputStream out;
-        SourceFile extern = SourceFile.fromCode("externs.js", "");
+
-        SourceFile input = SourceFile.fromCode(sourcePath, code);
+    private int theA;
-        compiler.compile(extern, input, options);
+    private int theB;
-        return compiler.toSource();
+
+    private JSMin(InputStream in, OutputStream out) {
+        this.in = new PushbackInputStream(in);
+        this.out = out;
+    }
+
+    /**
+     * isAlphanum -- return true if the character is a letter, digit,
+     * underscore, dollar sign, or non-ASCII character.
+     */
+    private static boolean isAlphanum(int c) {
+        return ((c >= 'a' && c <= 'z') ||
+                (c >= '0' && c <= '9') ||
+                (c >= 'A' && c <= 'Z') ||
+                c == '_' ||
+                c == '$' ||
+                c == '\\' ||
+                c > 126);
+    }
+
+    /**
+     * get -- return the next character from stdin. Watch out for lookahead. If
+     * the character is a control character, translate it to a space or
+     * linefeed.
+     */
+    private int get() throws IOException {
+        int c = in.read();
+
+        if (c >= ' ' || c == '\n' || c == EOF) {
+            return c;
+        }
+
+        if (c == '\r') {
+            return '\n';
+        }
+
+        return ' ';
+    }
+
+
+    /**
+     * Get the next character without getting it.
+     */
+    private int peek() throws IOException {
+        int lookaheadChar = in.read();
+        in.unread(lookaheadChar);
+        return lookaheadChar;
+    }
+
+    /**
+     * next -- get the next character, excluding comments. peek() is used to see
+     * if a '/' is followed by a '/' or '*'.
+     */
+    private int next() throws IOException, UnterminatedCommentException {
+        int c = get();
+        if (c == '/') {
+            switch (peek()) {
+                case '/':
+                    for (; ; ) {
+                        c = get();
+                        if (c <= '\n') {
+                            return c;
                         }
                     }
+
+                case '*':
+                    get();
+                    for (; ; ) {
+                        switch (get()) {
+                            case '*':
+                                if (peek() == '/') {
+                                    get();
+                                    return ' ';
+                                }
+                                break;
+                            case EOF:
+                                throw new UnterminatedCommentException();
+                        }
+                    }
+
+                default:
+                    return c;
+            }
+
+        }
+        return c;
+    }
+
+    /**
+     * action -- do something! What you do is determined by the argument: 1
+     * Output A. Copy B to A. Get the next B. 2 Copy B to A. Get the next B.
+     * (Delete A). 3 Get the next B. (Delete B). action treats a string as a
+     * single character. Wow! action recognizes a regular expression if it is
+     * preceded by ( or , or =.
+     */
+
+    private void action(int d) throws IOException, UnterminatedRegExpLiteralException,
+                                      UnterminatedCommentException, UnterminatedStringLiteralException {
+        switch (d) {
+            case 1:
+                out.write(theA);
+            case 2:
+                theA = theB;
+
+                if (theA == '\'' || theA == '"') {
+                    for (; ; ) {
+                        out.write(theA);
+                        theA = get();
+                        if (theA == theB) {
+                            break;
+                        }
+                        if (theA <= '\n') {
+                            throw new UnterminatedStringLiteralException();
+                        }
+                        if (theA == '\\') {
+                            out.write(theA);
+                            theA = get();
+                        }
+                    }
+                }
+
+            case 3:
+                theB = next();
+                if (theB == '/' && (theA == '(' || theA == ',' || theA == '=')) {
+                    out.write(theA);
+                    out.write(theB);
+                    for (; ; ) {
+                        theA = get();
+                        if (theA == '/') {
+                            break;
+                        } else if (theA == '\\') {
+                            out.write(theA);
+                            theA = get();
+                        } else if (theA <= '\n') {
+                            throw new UnterminatedRegExpLiteralException();
+                        }
+                        out.write(theA);
+                    }
+                    theB = next();
+                }
+        }
+    }
+
+    /**
+     * jsmin -- Copy the input to the output, deleting the characters which are
+     * insignificant to JavaScript. Comments will be removed. Tabs will be
+     * replaced with spaces. Carriage returns will be replaced with linefeeds.
+     * Most spaces and linefeeds will be removed.
+     */
+    public void jsmin() throws IOException, UnterminatedRegExpLiteralException, UnterminatedCommentException, UnterminatedStringLiteralException {
+        theA = '\n';
+        action(3);
+        while (theA != EOF) {
+            switch (theA) {
+                case ' ':
+                    if (isAlphanum(theB)) {
+                        action(1);
+                    } else {
+                        action(2);
+                    }
+                    break;
+                case '\n':
+                    switch (theB) {
+                        case '{':
+                        case '[':
+                        case '(':
+                        case '+':
+                        case '-':
+                            action(1);
+                            break;
+                        case ' ':
+                            action(3);
+                            break;
+                        default:
+                            if (isAlphanum(theB)) {
+                                action(1);
+                            } else {
+                                action(2);
+                            }
+                    }
+                    break;
+                default:
+                    switch (theB) {
+                        case ' ':
+                            if (isAlphanum(theA)) {
+                                action(1);
+                                break;
+                            }
+                            action(3);
+                            break;
+                        case '\n':
+                            switch (theA) {
+                                case '}':
+                                case ']':
+                                case ')':
+                                case '+':
+                                case '-':
+                                case '"':
+                                case '\'':
+                                    action(1);
+                                    break;
+                                default:
+                                    if (isAlphanum(theA)) {
+                                        action(1);
+                                    } else {
+                                        action(3);
+                                    }
+                            }
+                            break;
+                        default:
+                            action(1);
+                            break;
+                    }
+            }
+        }
+        out.flush();
+    }
+
+    private class UnterminatedCommentException extends Exception {
+    }
+
+    private class UnterminatedStringLiteralException extends Exception {
+    }
+
+    private class UnterminatedRegExpLiteralException extends Exception {
+    }
+
+}

src/test/java/j2html/tags/TagCreatorTest.java

@@ -70,7 +70,7 @@ public class TagCreatorTest {
         assertEquals(text("<script> and \"</script>\"").render(), "&lt;script&gt; and &quot;&lt;/script&gt;&quot;");
         assertEquals(unsafeHtml("<script>").render(), "<script>");
         assertEquals(styleWithInlineFile_min("/test.css").render(), "<style>body{background:#daa520;margin-bottom:10px;margin-left:10px;margin-right:10px;margin-top:10px}</style>");
-        assertEquals(scriptWithInlineFile_min("/test.js").render(), "<script>(function(){console.log(15)})();</script>");
+        assertEquals(scriptWithInlineFile_min("/test.js").render(), "<script>(function(){var test=5;var tast=10;var testTast=test+tast;console.log(testTast);})();</script>");
         assertEquals(fileAsString("/test.html").render(), "<body>" + EOL + "    Any content" + EOL + "</body>" + EOL);
         assertEquals(fileAsEscapedString("/test.html").render(), "&lt;body&gt;" + EOL + "    Any content" + EOL + "&lt;/body&gt;" + EOL);
         assertEquals(fileAsString("/AnyContent.java").render(), "public class AnyContent{}" + EOL);