/**
* $Id: mxCellCodec.java,v 1.14 2011-07-07 10:12:24 gaudenz Exp $
* Copyright (c) 2006, Gaudenz Alder
*/
package com.mxgraph.io;
import java.util.Iterator;
import java.util.Map;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import com.mxgraph.model.mxCell;
/**
* Codec for mxCells. This class is created and registered
* dynamically at load time and used implicitely via mxCodec
* and the mxCodecRegistry.
*/
public class mxCellCodec extends mxObjectCodec
{
/**
* Constructs a new cell codec.
*/
public mxCellCodec()
{
this(new mxCell(), null, new String[] { "parent", "source", "target" },
null);
}
/**
* Constructs a new cell codec for the given template.
*/
public mxCellCodec(Object template)
{
this(template, null, null, null);
}
/**
* Constructs a new cell codec for the given arguments.
*/
public mxCellCodec(Object template, String[] exclude, String[] idrefs,
Map<String, String> mapping)
{
super(template, exclude, idrefs, mapping);
}
/**
* Excludes user objects that are XML nodes.
*/
public boolean isExcluded(Object obj, String attr, Object value,
boolean write)
{
return exclude.contains(attr)
|| (write && attr.equals("value") && value instanceof Node && ((Node) value)
.getNodeType() == Node.ELEMENT_NODE);
}
/**
* Encodes an mxCell and wraps the XML up inside the
* XML of the user object (inversion).
*/
public Node afterEncode(mxCodec enc, Object obj, Node node)
{
if (obj instanceof mxCell)
{
mxCell cell = (mxCell) obj;
if (cell.getValue() instanceof Node)
{
// Wraps the graphical annotation up in the
// user object (inversion) by putting the
// result of the default encoding into
// a clone of the user object (node type 1)
// and returning this cloned user object.
Element tmp = (Element) node;
node = enc.getDocument().importNode((Node) cell.getValue(),
true);
node.appendChild(tmp);
// Moves the id attribute to the outermost
// XML node, namely the node which denotes
// the object boundaries in the file.
String id = tmp.getAttribute("id");
((Element) node).setAttribute("id", id);
tmp.removeAttribute("id");
}
}
return node;
}
/**
* Decodes an mxCell and uses the enclosing XML node as
* the user object for the cell (inversion).
*/
public Node beforeDecode(mxCodec dec, Node node, Object obj)
{
Element inner = (Element) node;
if (obj instanceof mxCell)
{
mxCell cell = (mxCell) obj;
String classname = getName();
String nodeName = node.getNodeName();
// Handles aliased names
if (!nodeName.equals(classname))
{
String tmp = mxCodecRegistry.aliases.get(nodeName);
if (tmp != null)
{
nodeName = tmp;
}
}
if (!nodeName.equals(classname))
{
// Passes the inner graphical annotation node to the
// object codec for further processing of the cell.
Node tmp = inner.getElementsByTagName(classname).item(0);
if (tmp != null && tmp.getParentNode() == node)
{
inner = (Element) tmp;
// Removes annotation and whitespace from node
Node tmp2 = tmp.getPreviousSibling();
while (tmp2 != null && tmp2.getNodeType() == Node.TEXT_NODE)
{
Node tmp3 = tmp2.getPreviousSibling();
if (tmp2.getTextContent().trim().length() == 0)
{
tmp2.getParentNode().removeChild(tmp2);
}
tmp2 = tmp3;
}
// Removes more whitespace
tmp2 = tmp.getNextSibling();
while (tmp2 != null && tmp2.getNodeType() == Node.TEXT_NODE)
{
Node tmp3 = tmp2.getPreviousSibling();
if (tmp2.getTextContent().trim().length() == 0)
{
tmp2.getParentNode().removeChild(tmp2);
}
tmp2 = tmp3;
}
tmp.getParentNode().removeChild(tmp);
}
else
{
inner = null;
}
// Creates the user object out of the XML node
Element value = (Element) node.cloneNode(true);
cell.setValue(value);
String id = value.getAttribute("id");
if (id != null)
{
cell.setId(id);
value.removeAttribute("id");
}
}
else
{
cell.setId(((Element) node).getAttribute("id"));
}
// Preprocesses and removes all Id-references
// in order to use the correct encoder (this)
// for the known references to cells (all).
if (inner != null && idrefs != null)
{
Iterator<String> it = idrefs.iterator();
while (it.hasNext())
{
String attr = it.next();
String ref = inner.getAttribute(attr);
if (ref != null && ref.length() > 0)
{
inner.removeAttribute(attr);
Object object = dec.objects.get(ref);
if (object == null)
{
object = dec.lookup(ref);
}
if (object == null)
{
// Needs to decode forward reference
Node element = dec.getElementById(ref);
if (element != null)
{
mxObjectCodec decoder = mxCodecRegistry
.getCodec(element.getNodeName());
if (decoder == null)
{
decoder = this;
}
object = decoder.decode(dec, element);
}
}
setFieldValue(obj, attr, object);
}
}
}
}
return inner;
}
}