[Java] Web Resource Compressor Framework

Java 에서 쓸 수 있는 Web Resource Compressor  관련 Framework 에 대해 간단히 소개해보고자 한다.

Web Resource Compressor  란 html, javascript, css 파일에 대한 Minifier, Beautifier 등의 기능을 수행하는 것을 말한다.

일종의 Web Resource 최적화 Framework 중 하나이다.

- Introduction

• Minifier
• HTML / XML
• HTML Compressor and MinifierHTML
• Project Home: https://code.google.com/p/htmlcompressor/
• Library: htmlcompressor-1.5.3.jar (v 1.5.3)
• Release Date: 2012-03
• License: Apache License 2.0
• Javascript / CSS
• YUI Compressor
• Project Home: http://yui.github.io/yuicompressor/
• Library: yuicompressor-2.4.7.jar (v 2.4.7)
• Release Date: 2011-09-06
• License: BSD License

• Beautifier
• HTML / JavaScript / CSS
• js-beautify
• Project Home: http://jsbeautifier.org/
• Library: beautify.js, beautify-css.js, beautify-html.js (v 1.3.2)
• Release Date: 2013-04-29
• License: MIT License
• 참고
• js-beautify 는 javascript 라이브러리 이기때문에 JAVA 에서 사용하기 위해서는 Rhino 엔진을 사용한다.
• Rhino
• Project Home: https://developer.mozilla.org/en-US/docs/tag/Rhino
• Library: js.jar (Rhino 1.7R4)
• Release Date: 2012-06-18
• License: MPL 2.0 License

- How to use?

• HTML Minifier - HTML Compressor 

    public void compress(InputStream source, OutputStream target) throws IOException {
        HtmlCompressor compressor = new HtmlCompressor();
        compressor.setCompressJavaScript(true); // compress inline css
        compressor.setCompressCss(true);        // compress inline javascript

        String compressedHtml = compressor.compress( IOUtil.getString( source, true ) );
        target.write( compressedHtml.getBytes() );
    }

• XML Minifier - HTML Compressor 

    public void compress(InputStream source, OutputStream target) throws IOException {
        XmlCompressor compressor = new XmlCompressor();

        String compressedXml = compressor.compress( IOUtil.getString( source, true ) );
        target.write( compressedXml.getBytes() );
    }

• JavaScript Minifier - YUI Compressor 

    public void compress( InputStream source, OutputStream target ) throws EvaluatorException, IOException {
        InputStreamReader reader = null;
        OutputStreamWriter writer = null;
        try {
            reader = new InputStreamReader(source);
            writer = new OutputStreamWriter(target);
            JavaScriptCompressor compressor = new JavaScriptCompressor( reader,new ErrorReporter() {
                @Override
                public void warning(String message, String sourceName, int line, String lineSource, int lineOffset) {
                    if (line < 0) {
                        logger.warn(message);
                    } else {
                        String logMessage = line + " : " + lineOffset + " : " + message;
                        logger.warn(logMessage);
                    }
                }
                @Override
                public void error(String message, String sourceName, int line, String lineSource, int lineOffset)  {
                    if (line < 0) {
                        logger.error(message);
                    } else {
                        String logMessage = line + " : " + lineOffset + " : " + message;
                        logger.error(logMessage);
                    }
                }
                @Override
                public EvaluatorException runtimeError(String message, String sourceName, int line, String lineSource, int lineOffset) {
                    error(message, sourceName, line, lineSource, lineOffset);
                    return new EvaluatorException(message);
                }
            });

            // (out, linebreak, munge, verbose, preserveAllSemiColons, disableOptimizations)
            compressor.compress( writer, -1, true, false, true, false);

        } catch (EvaluatorException e) {
            throw e;
        } catch (IOException e) {
            throw e;
        } finally {
            if ( reader != null ) { reader.close() };
            if ( writer != null ) { writer.close() };
        }
    }

• CSS Minifier - YUI Compressor 

    public void compress(InputStream source, OutputStream target) throws IOException {
        InputStreamReader reader = null;
        OutputStreamWriter writer = null;
        try {
            reader = new InputStreamReader(source);
            writer = new OutputStreamWriter(target);
            CssCompressor compressor = new CssCompressor(reader);
            compressor.compress(writer, -1);
        } catch (IOException e) {
            throw e;
        } finally {
            if ( reader != null ) { reader.close() };
            if ( writer != null ) { writer.close() };
        }
    }