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1   /**
2    * BSD-style license; for more info see http://pmd.sourceforge.net/license.html
3    */
4   
5   package net.sourceforge.pmd.renderers;
6   
7   import java.io.ByteArrayInputStream;
8   import java.io.File;
9   import java.io.FileInputStream;
10  import java.io.FileNotFoundException;
11  import java.io.IOException;
12  import java.io.InputStream;
13  import java.io.StringWriter;
14  import java.io.Writer;
15  
16  import javax.xml.parsers.DocumentBuilder;
17  import javax.xml.parsers.DocumentBuilderFactory;
18  import javax.xml.parsers.ParserConfigurationException;
19  import javax.xml.transform.Transformer;
20  import javax.xml.transform.TransformerConfigurationException;
21  import javax.xml.transform.TransformerException;
22  import javax.xml.transform.TransformerFactory;
23  import javax.xml.transform.dom.DOMSource;
24  import javax.xml.transform.stream.StreamResult;
25  import javax.xml.transform.stream.StreamSource;
26  
27  import org.w3c.dom.Document;
28  import org.xml.sax.SAXException;
29  
30  /**
31   * @author Romain Pelisse, belaran@gmail.com
32   *
33   */
34  public class XSLTRenderer extends XMLRenderer {
35  
36  	private Transformer transformer;
37  	private String xsltFilename = "/etc/pmd-nicerhtml.xsl";
38  	private Writer outputWriter;
39  
40  	public XSLTRenderer() {
41  
42  	}
43  	/**
44  	 * This constuctor provides a way to override default stylesheet
45  	 * @param xsltFilename
46  	 */
47  	public XSLTRenderer(String xsltFilename) {
48  		File file = new File(xsltFilename);
49  		if ( xsltFilename != null && file.exists() && file.canRead() ) {
50  			this.xsltFilename = xsltFilename;
51  		}
52  	}
53  
54  	@Override
55  	public void start() throws IOException {
56  		// We keep the inital writer to put the final html output
57  		this.outputWriter = getWriter();
58  		// We use a new one to store the XML...
59  		Writer w = new StringWriter();
60  		setWriter(w);
61  		// If don't find the xsl no need to bother doing the all report,
62  		// so we check this here...
63  		InputStream xslt = null;
64  		File file = new File(this.xsltFilename);
65  		if ( file.exists() && file.canRead() ) {
66  			xslt = new FileInputStream(file);
67  		}
68  		else {
69  			xslt = this.getClass().getResourceAsStream(xsltFilename);
70  		}
71  		if ( xslt == null ) {
72  			throw new FileNotFoundException("Can't file XSLT sheet :" + xsltFilename);
73  		}
74  		this.prepareTransformer(xslt);
75  		// Now we build the XML file
76  		super.start();
77  	}
78  
79  	/**
80  	 * Prepare the transformer, doing the proper "building"...
81  	 *
82  	 * @param xslt, the xslt provided as an InputStream
83  	 */
84  	private void prepareTransformer(InputStream xslt) {
85  		if ( xslt != null ) {
86  			try {
87  		    //Get a TransformerFactory object
88  		    TransformerFactory factory = TransformerFactory.newInstance();
89  		    StreamSource src = new StreamSource(xslt);
90  		    //Get an XSL Transformer object
91  		    this.transformer = factory.newTransformer(src);
92  			} catch (TransformerConfigurationException e) {
93  				e.printStackTrace();
94  			}
95  		}
96  	}
97  
98  	@Override
99  	public void end() throws IOException {
100 		// First we finish the XML report
101 		super.end();
102 		// Now we transform it using XSLT
103 		Writer writer = super.getWriter();
104 		if ( writer instanceof StringWriter ) {
105 			StringWriter w = (StringWriter)writer;
106 			StringBuffer buffer = w.getBuffer();
107 			// FIXME: If we change the encoding in XMLRenderer, we should change this too !
108 			InputStream xml =  new ByteArrayInputStream(buffer.toString().getBytes(this.encoding));
109 			Document doc = this.getDocument(xml);
110 			this.transform(doc);
111 		}
112 		else {
113 			// Should not happen !
114 			new RuntimeException("Wrong writer").printStackTrace();
115 		}
116 
117 	}
118 
119 	private void transform(Document doc) {
120 		DOMSource source = new DOMSource(doc);
121 		this.setWriter(new StringWriter());
122 		StreamResult result = new StreamResult(this.outputWriter);
123 		try {
124 			transformer.transform(source, result);
125 		} catch (TransformerException e) {
126 			e.printStackTrace();
127 		}
128 	}
129 
130 	private Document getDocument(InputStream xml) {
131 		try {
132 			DocumentBuilder parser = DocumentBuilderFactory.newInstance().newDocumentBuilder();
133 			return parser.parse(xml);
134 		} catch (ParserConfigurationException e) {
135 			e.printStackTrace();
136 		} catch (SAXException e) {
137 			e.printStackTrace();
138 		} catch (IOException e) {
139 			e.printStackTrace();
140 		}
141 		return null;
142 	}
143 }