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Diffstat (limited to 'id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/protocols/pvp2x/utils/PrettyPrinter.java')
| -rw-r--r-- | id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/protocols/pvp2x/utils/PrettyPrinter.java | 301 |
1 files changed, 301 insertions, 0 deletions
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/protocols/pvp2x/utils/PrettyPrinter.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/protocols/pvp2x/utils/PrettyPrinter.java new file mode 100644 index 000000000..807da0ebe --- /dev/null +++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/protocols/pvp2x/utils/PrettyPrinter.java @@ -0,0 +1,301 @@ +package at.gv.egovernment.moa.id.protocols.pvp2x.utils; + +import java.io.*; +import javax.xml.parsers.*; +import javax.xml.transform.*; +import javax.xml.transform.dom.*; +import javax.xml.transform.stream.*; + +import org.w3c.dom.Document; + +import org.xml.sax.*; +import org.xml.sax.helpers.*; + + +/** +This class "pretty prints" an XML stream to something more human-readable. +It duplicates the character content with some modifications to whitespace, +restoring line breaks and a simple pattern of indenting child elements. + +This version of the class acts as a SAX 2.0 <code>DefaultHandler</code>, +so to provide the unformatted XML just pass a new instance to a SAX parser. +Its output is via the {@link #toString toString} method. + +One major limitation: we gather character data for elements in a single +buffer, so mixed-content documents will lose a lot of data! This works +best with data-centric documents where elements either have single values +or child elements, but not both. + +@author Will Provost +*/ +/* +Copyright 2002-2003 by Will Provost. +All rights reserved. +*/ +public class PrettyPrinter + extends DefaultHandler +{ + /** + Convenience method to wrap pretty-printing SAX pass over existing content. + */ + public static String prettyPrint (byte[] content) + { + try + { + PrettyPrinter pretty = new PrettyPrinter (); + SAXParserFactory factory = SAXParserFactory.newInstance (); + factory.setFeature + ("http://xml.org/sax/features/namespace-prefixes", true); + factory.newSAXParser ().parse + (new ByteArrayInputStream (content), pretty); + return pretty.toString (); + } + catch (Exception ex) + { + ex.printStackTrace (); + return "EXCEPTION: " + ex.getClass ().getName () + " saying \"" + + ex.getMessage () + "\""; + } + } + + /** + Convenience method to wrap pretty-printing SAX pass over existing content. + */ + public static String prettyPrint (String content) + { + try + { + PrettyPrinter pretty = new PrettyPrinter (); + SAXParserFactory factory = SAXParserFactory.newInstance (); + factory.setFeature + ("http://xml.org/sax/features/namespace-prefixes", true); + factory.newSAXParser ().parse (content, pretty); + return pretty.toString (); + } + catch (Exception ex) + { + ex.printStackTrace (); + return "EXCEPTION: " + ex.getClass ().getName () + " saying \"" + + ex.getMessage () + "\""; + } + } + + /** + Convenience method to wrap pretty-printing SAX pass over existing content. + */ + public static String prettyPrint (InputStream content) + { + try + { + PrettyPrinter pretty = new PrettyPrinter (); + SAXParserFactory factory = SAXParserFactory.newInstance (); + factory.setFeature + ("http://xml.org/sax/features/namespace-prefixes", true); + factory.newSAXParser ().parse (content, pretty); + return pretty.toString (); + } + catch (Exception ex) + { + ex.printStackTrace (); + return "EXCEPTION: " + ex.getClass ().getName () + " saying \"" + + ex.getMessage () + "\""; + } + } + + /** + Convenience method to wrap pretty-printing SAX pass over existing content. + */ + public static String prettyPrint (Document doc) + throws TransformerException + { + try + { + ByteArrayOutputStream buffer = new ByteArrayOutputStream (); + TransformerFactory.newInstance ().newTransformer() + .transform (new DOMSource (doc), new StreamResult (buffer)); + byte[] rawResult = buffer.toByteArray (); + buffer.close (); + + return prettyPrint (rawResult); + } + catch (Exception ex) + { + ex.printStackTrace (); + return "EXCEPTION: " + ex.getClass ().getName () + " saying \"" + + ex.getMessage () + "\""; + } + } + + public static class StreamAdapter + extends OutputStream + { + public StreamAdapter (Writer finalDestination) + { + this.finalDestination = finalDestination; + } + + public void write (int b) + { + out.write (b); + } + + public void flushPretty () + throws IOException + { + PrintWriter finalPrinter = new PrintWriter (finalDestination); + finalPrinter.println + (PrettyPrinter.prettyPrint (out.toByteArray ())); + finalPrinter.close (); + out.close (); + } + + private ByteArrayOutputStream out = new ByteArrayOutputStream (); + Writer finalDestination; + } + + /** + Call this to get the formatted XML post-parsing. + */ + public String toString () + { + return output.toString (); + } + + /** + Prints the XML declaration. + */ + public void startDocument () + throws SAXException + { + output.append ("<?xml version=\"1.0\" encoding=\"UTF-8\" ?>") + .append (endLine); + } + + /** + Prints a blank line at the end of the reformatted document. + */ + public void endDocument () throws SAXException + { + output.append (endLine); + } + + /** + Writes the start tag for the element. + Attributes are written out, one to a text line. Starts gathering + character data for the element. + */ + public void startElement + (String URI, String name, String qName, Attributes attributes) + throws SAXException + { + if (justHitStartTag) + output.append ('>'); + + output.append (endLine) + .append (indent) + .append ('<') + .append (qName); + + int length = attributes.getLength (); + for (int a = 0; a < length; ++a) + output.append (endLine) + .append (indent) + .append (standardIndent) + .append (attributes.getQName (a)) + .append ("=\"") + .append (attributes.getValue (a)) + .append ('\"'); + + if (length > 0) + output.append (endLine) + .append (indent); + + indent += standardIndent; + currentValue = new StringBuffer (); + justHitStartTag = true; + } + + /** + Checks the {@link #currentValue} buffer to gather element content. + Writes this out if it is available. Writes the element end tag. + */ + public void endElement (String URI, String name, String qName) + throws SAXException + { + indent = indent.substring + (0, indent.length () - standardIndent.length ()); + + if (currentValue == null) + output.append (endLine) + .append (indent) + .append ("</") + .append (qName) + .append ('>'); + else if (currentValue.length () != 0) + output.append ('>') + .append (currentValue.toString ()) + .append ("</") + .append (qName) + .append ('>'); + else + output.append ("/>"); + + currentValue = null; + justHitStartTag = false; + } + + /** + When the {@link #currentValue} buffer is enabled, appends character + data into it, to be gathered when the element end tag is encountered. + */ + public void characters (char[] chars, int start, int length) + throws SAXException + { + if (currentValue != null) + currentValue.append (escape (chars, start, length)); + } + + /** + Filter to pass strings to output, escaping <b><</b> and <b>&</b> + characters to &lt; and &amp; respectively. + */ + private static String escape (char[] chars, int start, int length) + { + StringBuffer result = new StringBuffer (); + for (int c = start; c < start + length; ++c) + if (chars[c] == '<') + result.append ("<"); + else if (chars[c] == '&') + result.append ("&"); + else + result.append (chars[c]); + + return result.toString (); + } + + /** + This whitespace string is expanded and collapsed to manage the output + indenting. + */ + private String indent = ""; + + /** + A buffer for character data. It is "enabled" in + {@link #startElement startElement} by being initialized to a + new <b>StringBuffer</b>, and then read and reset to + <code>null</code> in {@link #endElement endElement}. + */ + private StringBuffer currentValue = null; + + /** + The primary buffer for accumulating the formatted XML. + */ + private StringBuffer output = new StringBuffer (); + + private boolean justHitStartTag; + + private static final String standardIndent = " "; + private static final String endLine = + System.getProperty ("line.separator"); +} + |