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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package com.sun.tools.internal.xjc.reader.internalizer;

import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.text.ParseException;

import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;

import com.sun.istack.internal.SAXParseException2;
import com.sun.istack.internal.NotNull;
import com.sun.istack.internal.Nullable;
import com.sun.tools.internal.xjc.ErrorReceiver;
import com.sun.tools.internal.xjc.reader.Const;
import com.sun.tools.internal.xjc.util.DOMUtils;
import com.sun.xml.internal.bind.v2.util.EditDistance;
import com.sun.xml.internal.bind.v2.util.XmlFactory;
import com.sun.xml.internal.xsom.SCD;
import java.io.File;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.xml.XMLConstants;

import org.w3c.dom.Attr;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXParseException;

Internalizes external binding declarations.
 The transform(DOMForest, boolean) method is the entry point. 
Author:

    Kohsuke Kawaguchi (kohsuke.kawaguchi@sun.com)/**
 * Internalizes external binding declarations.
 *
 * <p>
 * The {@link #transform(DOMForest,boolean)} method is the entry point.
 *
 * @author
 *     Kohsuke Kawaguchi (kohsuke.kawaguchi@sun.com)
 */
class Internalizer {

    private static final String WSDL_NS = "http://schemas.xmlsoap.org/wsdl/";

    private final XPath xpath;

    
Internalize all <jaxb:bindings> customizations in the given forest. 
Returns:

     if the SCD support is enabled, the return bindings need to be applied
     after schema components are parsed.
     If disabled, the returned binding set will be empty.
     SCDs are only for XML Schema, and doesn't make any sense for other
     schema languages./**
     * Internalize all {@code <jaxb:bindings>} customizations in the given forest.
     *
     * @return
     *      if the SCD support is enabled, the return bindings need to be applied
     *      after schema components are parsed.
     *      If disabled, the returned binding set will be empty.
     *      SCDs are only for XML Schema, and doesn't make any sense for other
     *      schema languages.
     */
    static SCDBasedBindingSet transform( DOMForest forest, boolean enableSCD, boolean disableSecureProcessing ) {
        return new Internalizer(forest, enableSCD, disableSecureProcessing).transform();
    }


    private Internalizer(DOMForest forest, boolean enableSCD, boolean disableSecureProcessing) {
        this.errorHandler = forest.getErrorHandler();
        this.forest = forest;
        this.enableSCD = enableSCD;
        xpath = XmlFactory.createXPathFactory(disableSecureProcessing).newXPath();
    }

    
DOMForest object currently being processed.
/**
     * DOMForest object currently being processed.
     */
    private final DOMForest forest;

    
All errors found during the transformation is sent to this object.
/**
     * All errors found during the transformation is sent to this object.
     */
    private ErrorReceiver errorHandler;

    
If true, the SCD-based target selection is supported.
/**
     * If true, the SCD-based target selection is supported.
     */
    private boolean enableSCD;


    private SCDBasedBindingSet transform() {

        // either target nodes are conventional DOM nodes (as per spec),
        Map<Element,List<Node>> targetNodes = new HashMap<Element,List<Node>>();
        // ... or it will be schema components by means of SCD (RI extension)
        SCDBasedBindingSet scd = new SCDBasedBindingSet(forest);

        //
        // identify target nodes for all <jaxb:bindings>
        //
        for (Element jaxbBindings : forest.outerMostBindings) {
            // initially, the inherited context is itself
            buildTargetNodeMap(jaxbBindings, jaxbBindings, null, targetNodes, scd);
        }

        //
        // then move them to their respective positions.
        //
        for (Element jaxbBindings : forest.outerMostBindings) {
            move(jaxbBindings, targetNodes);
        }

        return scd;
    }

    
Determines the target node of the "bindings" element
by using the inherited target node, then put
the result into the "result" map and the "scd" map.
Params:
inheritedTarget – 
     The current target node. This always exists, even if
     the user starts specifying targets via SCD (in that case
     this inherited target is just not going to be used.)
inheritedSCD –  If the ancestor <bindings> node specifies @scd to specify the target via SCD, then this parameter represents that context./**
     * Determines the target node of the "bindings" element
     * by using the inherited target node, then put
     * the result into the "result" map and the "scd" map.
     *
     * @param inheritedTarget
     *      The current target node. This always exists, even if
     *      the user starts specifying targets via SCD (in that case
     *      this inherited target is just not going to be used.)
     * @param inheritedSCD
     *      If the ancestor {@code <bindings>} node specifies @scd to
     *      specify the target via SCD, then this parameter represents that context.
     */
    private void buildTargetNodeMap( Element bindings, @NotNull Node inheritedTarget,
                                     @Nullable SCDBasedBindingSet.Target inheritedSCD,
                                     Map<Element,List<Node>> result, SCDBasedBindingSet scdResult ) {
        // start by the inherited target
        Node target = inheritedTarget;
        ArrayList<Node> targetMultiple = null;

        // validate this node ?
        // validate(bindings);

        boolean required = true;
        boolean multiple = false;

        if(bindings.getAttribute("required") != null) {
            String requiredAttr = bindings.getAttribute("required");

            if(requiredAttr.equals("no") || requiredAttr.equals("false") || requiredAttr.equals("0"))
                required = false;
        }

        if(bindings.getAttribute("multiple") != null) {
            String requiredAttr = bindings.getAttribute("multiple");

            if(requiredAttr.equals("yes") || requiredAttr.equals("true") || requiredAttr.equals("1"))
                multiple = true;
        }


        // look for @schemaLocation
        if( bindings.getAttributeNode("schemaLocation")!=null ) {
            String schemaLocation = bindings.getAttribute("schemaLocation");

            // enhancement - schemaLocation="*" = bind to all schemas..
            if(schemaLocation.equals("*")) {
                for(String systemId : forest.listSystemIDs()) {
                    if (result.get(bindings) == null)
                        result.put(bindings, new ArrayList<Node>());
                    result.get(bindings).add(forest.get(systemId).getDocumentElement());

                    Element[] children = DOMUtils.getChildElements(bindings, Const.JAXB_NSURI, "bindings");
                    for (Element value : children)
                        buildTargetNodeMap(value, forest.get(systemId).getDocumentElement(), inheritedSCD, result, scdResult);
                }
                return;
            } else {
                try {
                    // TODO: use the URI class
                    // TODO: honor xml:base
                    URL loc = new URL(
                                new URL(forest.getSystemId(bindings.getOwnerDocument())), schemaLocation
                              );
                    schemaLocation = loc.toExternalForm();
                    target = forest.get(schemaLocation);
                    if ((target == null) && (loc.getProtocol().startsWith("file"))) {
                        File f = new File(loc.getFile());
                        schemaLocation = new File(f.getCanonicalPath()).toURI().toString();
                    }
                } catch( MalformedURLException e ) {
                } catch( IOException e ) {
                    Logger.getLogger(Internalizer.class.getName()).log(Level.FINEST, e.getLocalizedMessage());
                }

                target = forest.get(schemaLocation);
                if(target==null) {
                    reportError( bindings,
                        Messages.format(Messages.ERR_INCORRECT_SCHEMA_REFERENCE,
                            schemaLocation,
                            EditDistance.findNearest(schemaLocation,forest.listSystemIDs())));

                    return; // abort processing this <jaxb:bindings>
                }

                target = ((Document)target).getDocumentElement();
            }
        }

        // look for @node
        if( bindings.getAttributeNode("node")!=null ) {
            String nodeXPath = bindings.getAttribute("node");

            // evaluate this XPath
            NodeList nlst;
            try {
                xpath.setNamespaceContext(new NamespaceContextImpl(bindings));
                nlst = (NodeList)xpath.evaluate(nodeXPath,target,XPathConstants.NODESET);
            } catch (XPathExpressionException e) {
                if(required) {
                    reportError( bindings,
                        Messages.format(Messages.ERR_XPATH_EVAL,e.getMessage()), e );
                    return; // abort processing this <jaxb:bindings>
                } else {
                    return;
                }
            }

            if( nlst.getLength()==0 ) {
                if(required)
                    reportError( bindings,
                        Messages.format(Messages.NO_XPATH_EVAL_TO_NO_TARGET, nodeXPath) );
                return; // abort
            }

            if( nlst.getLength()!=1 ) {
                if(!multiple) {
                    reportError( bindings,
                        Messages.format(Messages.NO_XPATH_EVAL_TOO_MANY_TARGETS, nodeXPath,nlst.getLength()) );

                    return; // abort
                } else {
                    if(targetMultiple == null) targetMultiple = new ArrayList<Node>();
                    for(int i = 0; i < nlst.getLength(); i++) {
                        targetMultiple.add(nlst.item(i));
                    }
                }
            }

            // check
            if(!multiple || nlst.getLength() == 1) {
                Node rnode = nlst.item(0);
                if (!(rnode instanceof Element)) {
                    reportError(bindings,
                            Messages.format(Messages.NO_XPATH_EVAL_TO_NON_ELEMENT, nodeXPath));
                    return; // abort
                }

                if (!forest.logic.checkIfValidTargetNode(forest, bindings, (Element) rnode)) {
                    reportError(bindings,
                            Messages.format(Messages.XPATH_EVAL_TO_NON_SCHEMA_ELEMENT,
                            nodeXPath, rnode.getNodeName()));
                    return; // abort
                }

                target = rnode;
            } else {
                for(Node rnode : targetMultiple) {
                    if (!(rnode instanceof Element)) {
                        reportError(bindings,
                                Messages.format(Messages.NO_XPATH_EVAL_TO_NON_ELEMENT, nodeXPath));
                        return; // abort
                    }

                    if (!forest.logic.checkIfValidTargetNode(forest, bindings, (Element) rnode)) {
                        reportError(bindings,
                                Messages.format(Messages.XPATH_EVAL_TO_NON_SCHEMA_ELEMENT,
                                nodeXPath, rnode.getNodeName()));
                        return; // abort
                    }
                }
            }
        }

        // look for @scd
        if( bindings.getAttributeNode("scd")!=null ) {
            String scdPath = bindings.getAttribute("scd");
            if(!enableSCD) {
                // SCD selector was found, but it's not activated. report an error
                // but recover by handling it anyway. this also avoids repeated error messages.
                reportError(bindings,
                    Messages.format(Messages.SCD_NOT_ENABLED));
                enableSCD = true;
            }

            try {
                inheritedSCD = scdResult.createNewTarget( inheritedSCD, bindings,
                        SCD.create(scdPath, new NamespaceContextImpl(bindings)) );
            } catch (ParseException e) {
                reportError( bindings, Messages.format(Messages.ERR_SCD_EVAL,e.getMessage()),e );
                return; // abort processing this bindings
            }
        }

        // update the result map
        if (inheritedSCD != null) {
            inheritedSCD.addBinidng(bindings);
        } else if (!multiple || targetMultiple == null) {
            if (result.get(bindings) == null)
                result.put(bindings, new ArrayList<Node>());
            result.get(bindings).add(target);
        } else {
            for (Node rnode : targetMultiple) {
                if (result.get(bindings) == null)
                    result.put(bindings, new ArrayList<Node>());

                result.get(bindings).add(rnode);
            }

        }


        // look for child <jaxb:bindings> and process them recursively
        Element[] children = DOMUtils.getChildElements( bindings, Const.JAXB_NSURI, "bindings" );
        for (Element value : children)
            if(!multiple || targetMultiple == null)
                buildTargetNodeMap(value, target, inheritedSCD, result, scdResult);
            else {
                for(Node rnode : targetMultiple) {
                    buildTargetNodeMap(value, rnode, inheritedSCD, result, scdResult);
                }
            }
    }

    
Moves JAXB customizations under their respective target nodes.
/**
     * Moves JAXB customizations under their respective target nodes.
     */
    private void move(Element bindings, Map<Element, List<Node>> targetNodes) {
        List<Node> nodelist = targetNodes.get(bindings);

        if(nodelist == null) {
                return; // abort
        }

        for (Node target : nodelist) {
            if (target == null) // this must be the result of an error on the external binding.
            // recover from the error by ignoring this node
            {
                return;
            }

            for (Element item : DOMUtils.getChildElements(bindings)) {
                String localName = item.getLocalName();

                if ("bindings".equals(localName)) {
                    // process child <jaxb:bindings> recursively
                    move(item, targetNodes);
                } else if ("globalBindings".equals(localName)) {
                        // <jaxb:globalBindings> always go to the root of document.
                    Element root = forest.getOneDocument().getDocumentElement();
                    if (root.getNamespaceURI().equals(WSDL_NS)) {
                        NodeList elements = root.getElementsByTagNameNS(XMLConstants.W3C_XML_SCHEMA_NS_URI, "schema");
                        if ((elements == null) || (elements.getLength() < 1)) {
                            reportError(item, Messages.format(Messages.ORPHANED_CUSTOMIZATION, item.getNodeName()));
                            return;
                        } else {
                            moveUnder(item, (Element)elements.item(0));
                        }
                    } else {
                        moveUnder(item, root);
                    }
                } else {
                    if (!(target instanceof Element)) {
                        reportError(item,
                                Messages.format(Messages.CONTEXT_NODE_IS_NOT_ELEMENT));
                        return; // abort
                    }

                    if (!forest.logic.checkIfValidTargetNode(forest, item, (Element) target)) {
                        reportError(item,
                                Messages.format(Messages.ORPHANED_CUSTOMIZATION, item.getNodeName()));
                        return; // abort
                    }

                    // move this node under the target
                    moveUnder(item, (Element) target);
                }
            }
        }
    }

    
Moves the "decl" node under the "target" node.
Params:
decl –  A JAXB customization element (e.g., <jaxb:class>)
target –  XML Schema element under which the declaration should move. For example, <xs:element>/**
     * Moves the "decl" node under the "target" node.
     *
     * @param decl
     *      A JAXB customization element (e.g., {@code <jaxb:class>})
     *
     * @param target
     *      XML Schema element under which the declaration should move.
     *      For example, {@code <xs:element>}
     */
    private void moveUnder( Element decl, Element target ) {
        Element realTarget = forest.logic.refineTarget(target);

        declExtensionNamespace( decl, target );

        // copy in-scope namespace declarations of the decl node
        // to the decl node itself so that this move won't change
        // the in-scope namespace bindings.
        Element p = decl;
        Set<String> inscopes = new HashSet<String>();
        while(true) {
            NamedNodeMap atts = p.getAttributes();
            for( int i=0; i<atts.getLength(); i++ ) {
                Attr a = (Attr)atts.item(i);
                if( Const.XMLNS_URI.equals(a.getNamespaceURI()) ) {
                    String prefix;
                    if( a.getName().indexOf(':')==-1 )  prefix = "";
                    else                                prefix = a.getLocalName();

                    if( inscopes.add(prefix) && p!=decl ) {
                        // if this is the first time we see this namespace bindings,
                        // copy the declaration.
                        // if p==decl, there's no need to. Note that
                        // we want to add prefix to inscopes even if p==Decl

                        decl.setAttributeNodeNS( (Attr)a.cloneNode(true) );
                    }
                }
            }

            if( p.getParentNode() instanceof Document )
                break;

            p = (Element)p.getParentNode();
        }

        if( !inscopes.contains("") ) {
            // if the default namespace was undeclared in the context of decl,
            // it must be explicitly set to "" since the new environment might
            // have a different default namespace URI.
            decl.setAttributeNS(Const.XMLNS_URI,"xmlns","");
        }


        // finally move the declaration to the target node.
        if( realTarget.getOwnerDocument()!=decl.getOwnerDocument() ) {
            // if they belong to different DOM documents, we need to clone them
            Element original = decl;
            decl = (Element)realTarget.getOwnerDocument().importNode(decl,true);

            // this effectively clones a ndoe,, so we need to copy locators.
            copyLocators( original, decl );
        }

        realTarget.appendChild( decl );
    }

    
Recursively visits sub-elements and declare all used namespaces.
TODO: the fact that we recognize all namespaces in the extension
is a bad design.
/**
     * Recursively visits sub-elements and declare all used namespaces.
     * TODO: the fact that we recognize all namespaces in the extension
     * is a bad design.
     */
    private void declExtensionNamespace(Element decl, Element target) {
        // if this comes from external namespaces, add the namespace to
        // @extensionBindingPrefixes.
        if( !Const.JAXB_NSURI.equals(decl.getNamespaceURI()) )
            declareExtensionNamespace( target, decl.getNamespaceURI() );

        NodeList lst = decl.getChildNodes();
        for( int i=0; i<lst.getLength(); i++ ) {
            Node n = lst.item(i);
            if( n instanceof Element )
                declExtensionNamespace( (Element)n, target );
        }
    }


    
Attribute name. /** Attribute name. */
    private static final String EXTENSION_PREFIXES = "extensionBindingPrefixes";

    
Adds the specified namespace URI to the jaxb:extensionBindingPrefixes
attribute of the target document.
/**
     * Adds the specified namespace URI to the jaxb:extensionBindingPrefixes
     * attribute of the target document.
     */
    private void declareExtensionNamespace( Element target, String nsUri ) {
        // look for the attribute
        Element root = target.getOwnerDocument().getDocumentElement();
        Attr att = root.getAttributeNodeNS(Const.JAXB_NSURI,EXTENSION_PREFIXES);
        if( att==null ) {
            String jaxbPrefix = allocatePrefix(root,Const.JAXB_NSURI);
            // no such attribute. Create one.
            att = target.getOwnerDocument().createAttributeNS(
                Const.JAXB_NSURI,jaxbPrefix+':'+EXTENSION_PREFIXES);
            root.setAttributeNodeNS(att);
        }

        String prefix = allocatePrefix(root,nsUri);
        if( att.getValue().indexOf(prefix)==-1 )
            // avoid redeclaring the same namespace twice.
            att.setValue( att.getValue()+' '+prefix);
    }

    
Declares a new prefix on the given element and associates it
with the specified namespace URI.

Note that this method doesn't use the default namespace
even if it can.
/**
     * Declares a new prefix on the given element and associates it
     * with the specified namespace URI.
     * <p>
     * Note that this method doesn't use the default namespace
     * even if it can.
     */
    private String allocatePrefix( Element e, String nsUri ) {
        // look for existing namespaces.
        NamedNodeMap atts = e.getAttributes();
        for( int i=0; i<atts.getLength(); i++ ) {
            Attr a = (Attr)atts.item(i);
            if( Const.XMLNS_URI.equals(a.getNamespaceURI()) ) {
                if( a.getName().indexOf(':')==-1 )  continue;

                if( a.getValue().equals(nsUri) )
                    return a.getLocalName();    // found one
            }
        }

        // none found. allocate new.
        while(true) {
            String prefix = "p"+(int)(Math.random()*1000000)+'_';
            if(e.getAttributeNodeNS(Const.XMLNS_URI,prefix)!=null)
                continue;   // this prefix is already allocated.

            e.setAttributeNS(Const.XMLNS_URI,"xmlns:"+prefix,nsUri);
            return prefix;
        }
    }


    
Copies location information attached to the "src" node to the "dst" node.
/**
     * Copies location information attached to the "src" node to the "dst" node.
     */
    private void copyLocators( Element src, Element dst ) {
        forest.locatorTable.storeStartLocation(
            dst, forest.locatorTable.getStartLocation(src) );
        forest.locatorTable.storeEndLocation(
            dst, forest.locatorTable.getEndLocation(src) );

        // recursively process child elements
        Element[] srcChilds = DOMUtils.getChildElements(src);
        Element[] dstChilds = DOMUtils.getChildElements(dst);

        for( int i=0; i<srcChilds.length; i++ )
            copyLocators( srcChilds[i], dstChilds[i] );
    }


    private void reportError( Element errorSource, String formattedMsg ) {
        reportError( errorSource, formattedMsg, null );
    }

    private void reportError( Element errorSource,
        String formattedMsg, Exception nestedException ) {

        SAXParseException e = new SAXParseException2( formattedMsg,
            forest.locatorTable.getStartLocation(errorSource),
            nestedException );
        errorHandler.error(e);
    }
}