Move ad hoc serializer to an "Unparser" class (ugly and unfinished).

2 files changed, 92 insertions, 47 deletions

diff --git a/org/madore/damlengine/DamlEngine.java b/org/madore/damlengine/DamlEngine.java
index ecbdefd..e5454da 100644
--- a/org/madore/damlengine/DamlEngine.java
+++ b/org/madore/damlengine/DamlEngine.java
@@ -1,5 +1,6 @@
 package org.madore.damlengine;
 
+import java.io.OutputStreamWriter;
 import javax.xml.parsers.DocumentBuilderFactory;
 import javax.xml.parsers.DocumentBuilder;
 import org.w3c.dom.*;
@@ -33,53 +34,9 @@ public final class DamlEngine {
 	for (String fname : args) {
 	    doc = db.parse(fname);
 	    processDocument();
-	    Node node0 = null;
-	    Node node = doc;
-	    while ( node != null || node0 != null ) {
-		if ( node != null && node.getNodeType() == Node.ELEMENT_NODE ) {
-		    Element elt = (Element)node;
-		    System.out.print("<"+elt.getTagName());
-		    if ( elt.hasAttributes() ) {
-			NamedNodeMap attrs = elt.getAttributes();
-			Node n2;
-			for ( int i=0 ; (n2=attrs.item(i)) != null ; i++ ) {
-			    Attr attr = (Attr)n2;
-			    System.out.print(" "+attr.getName()
-					     +"=\"(value)\"");
-			}
-		    }
-		    if ( ! elt.hasChildNodes() ) {
-			System.out.print(" />");
-			node = node.getNextSibling();
-		    } else {
-			System.out.print(">");
-			node0 = node;
-			node = node0.getFirstChild();
-		    }
-		} else if ( node != null && node.getNodeType() == Node.DOCUMENT_NODE ) {
-		    node0 = node;
-		    node = node0.getFirstChild();
-		} else if ( node != null ) {
-		    if ( node.getNodeType() == Node.TEXT_NODE ) {
-			System.out.print("(text)");
-		    } else if ( node.getNodeType() == Node.COMMENT_NODE ) {
-			System.out.print("<!--(comment)-->");
-		    } else if ( node.getNodeType() == Node.CDATA_SECTION_NODE ) {
-			System.out.print("<![CDATA[(cdata)]]>");
-		    } else {
-			System.out.print("<!--(some other kind of node)-->");
-		    }
-		    node = node.getNextSibling();
-		} else {
-		    node = node0;
-		    node0 = node.getParentNode();
-		    if ( node.getNodeType() == Node.ELEMENT_NODE ) {
-			Element elt = (Element)node;
-			System.out.print("</"+elt.getTagName()+">");
-		    }
-		    node = node.getNextSibling();
-		}
-	    }
+	    Unparser unparser
+		= new Unparser(doc, new OutputStreamWriter(System.out));
+	    unparser.unparse();
 	}
 
     }
diff --git a/org/madore/damlengine/Unparser.java b/org/madore/damlengine/Unparser.java
new file mode 100644
index 0000000..a903523
--- /dev/null
+++ b/org/madore/damlengine/Unparser.java
@@ -0,0 +1,88 @@
+package org.madore.damlengine;
+
+import java.io.Writer;
+import java.io.IOException;
+import org.w3c.dom.*;
+
+public final class Unparser {
+
+    private Node cursor;
+    private enum Dir { PUSHING, POPPING };
+    private Dir dir;
+    private Writer out;
+
+    public Unparser(Document doc, Writer out) {
+	cursor = doc;
+	dir = Dir.PUSHING;
+	this.out = out;
+    }
+
+    protected void skip() {
+	Node nsib = cursor.getNextSibling();
+	if ( nsib == null ) {
+	    cursor = cursor.getParentNode();
+	    dir = Dir.POPPING;
+	} else {
+	    cursor = nsib;
+	    dir = Dir.PUSHING;
+	}
+    }
+
+    protected void unparseOne()
+	throws IOException {
+	switch ( dir ) {
+	case PUSHING:
+	    if ( cursor.getNodeType() == Node.ELEMENT_NODE ) {
+		Element elt = (Element)cursor;
+		out.write("<"+elt.getTagName());
+		if ( elt.hasAttributes() ) {
+		    NamedNodeMap attrs = elt.getAttributes();
+		    Node n2;
+		    for ( int i=0 ; (n2=attrs.item(i)) != null ; i++ ) {
+			Attr attr = (Attr)n2;
+			out.write(" "+attr.getName()
+				  +"=\"(value)\"");
+		    }
+		}
+		if ( ! elt.hasChildNodes() ) {
+		    out.write(" />");
+		    skip();
+		} else {
+		    out.write(">");
+		    cursor = elt.getFirstChild();
+		}
+	    } else if ( cursor.getNodeType() == Node.DOCUMENT_NODE ) {
+		cursor = cursor.getFirstChild();
+		skip();
+	    } else if ( cursor.getNodeType() == Node.TEXT_NODE ) {
+		out.write("(text)");
+		skip();
+	    } else if ( cursor.getNodeType() == Node.COMMENT_NODE ) {
+		out.write("<!--(comment)-->");
+		skip();
+	    } else if ( cursor.getNodeType() == Node.CDATA_SECTION_NODE ) {
+		out.write("<![CDATA[(cdata)]]>");
+		skip();
+	    } else {
+		out.write("<!--(some other kind of node)-->");
+		skip();
+	    }
+	    break;
+	case POPPING:
+	    if ( cursor.getNodeType() == Node.ELEMENT_NODE ) {
+		Element elt = (Element)cursor;
+		out.write("</"+elt.getTagName()+">");
+	    }
+	    skip();
+	    break;
+	}
+    }
+
+    public void unparse()
+	throws IOException {
+	while ( cursor != null ) {
+	    unparseOne();
+	}
+    }
+
+}