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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

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 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

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 *

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package com.sun.xml.internal.bind.v2.runtime.unmarshaller;

import java.util.Collection;

import java.util.HashMap;

import java.util.Map;

import javax.xml.namespace.QName;

import com.sun.xml.internal.bind.api.AccessorException;

import com.sun.xml.internal.bind.v2.WellKnownNamespace;

import com.sun.xml.internal.bind.v2.runtime.ClassBeanInfoImpl;

import com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl;

import com.sun.xml.internal.bind.v2.runtime.JaxBeanInfo;

import com.sun.xml.internal.bind.v2.runtime.property.AttributeProperty;

import com.sun.xml.internal.bind.v2.runtime.property.Property;

import com.sun.xml.internal.bind.v2.runtime.property.StructureLoaderBuilder;

import com.sun.xml.internal.bind.v2.runtime.property.UnmarshallerChain;

import com.sun.xml.internal.bind.v2.runtime.reflect.Accessor;

import com.sun.xml.internal.bind.v2.runtime.reflect.TransducedAccessor;

import com.sun.xml.internal.bind.v2.util.QNameMap;

import java.util.Iterator;

import org.xml.sax.Attributes;

import org.xml.sax.SAXException;

/**

 * Loads children of an element.

 *

 * <p>

 * This loader works with a single {@link JaxBeanInfo} and handles

 * attributes, child elements, or child text.

 *

 * @author Kohsuke Kawaguchi

 */

public final class StructureLoader extends Loader {

    /**

     * This map statically stores information of the

     * unmarshaller loader and can be used while unmarshalling

     * Since creating new QNames is expensive use this optimized

     * version of the map

     */

    private final QNameMap<ChildLoader> childUnmarshallers = new QNameMap<ChildLoader>();

    /**

     * Loader that processes elements that didn't match anf of the {@link #childUnmarshallers}.

     * Can be null.

     */

    private /*final*/ ChildLoader catchAll;

    /**

     * If we have a loader for processing text. Otherwise null.

     */

    private /*final*/ ChildLoader textHandler;

    /**

     * Unmarshallers for attribute values.

     * May be null if no attribute is expected and {@link #attCatchAll}==null.

     */

    private /*final*/ QNameMap<TransducedAccessor> attUnmarshallers;

    /**

     * This will receive all the attributes

     * that were not processed. Never be null.

     */

    private /*final*/ Accessor<Object,Map<QName,String>> attCatchAll;

    private final JaxBeanInfo beanInfo;

    /**

     * The number of scopes this dispatcher needs to keep active.

     */

    private /*final*/ int frameSize;

    // this class is potentially useful for general audience, not just for ClassBeanInfoImpl,

    // but since right now that is the only user, we make the construction code very specific

    // to ClassBeanInfoImpl. See rev.1.5 of this file for the original general purpose definition.

    public StructureLoader(ClassBeanInfoImpl beanInfo) {

        super(true);

        this.beanInfo = beanInfo;

    }

    /**

     * Completes the initialization.

     *

     * <p>

     * To fix the cyclic reference issue, the main part of the initialization needs to be done

     * after a {@link StructureLoader} is set to {@link ClassBeanInfoImpl#loader}.

     */

    public void init( JAXBContextImpl context, ClassBeanInfoImpl beanInfo, Accessor<?,Map<QName,String>> attWildcard) {

        UnmarshallerChain chain = new UnmarshallerChain(context);

        for (ClassBeanInfoImpl bi = beanInfo; bi != null; bi = bi.superClazz) {

            for (int i = bi.properties.length - 1; i >= 0; i--) {

                Property p = bi.properties[i];

                switch(p.getKind()) {

                case ATTRIBUTE:

                    if(attUnmarshallers==null)

                        attUnmarshallers = new QNameMap<TransducedAccessor>();

                    AttributeProperty ap = (AttributeProperty) p;

                    attUnmarshallers.put(ap.attName.toQName(),ap.xacc);

                    break;

                case ELEMENT:

                case REFERENCE:

                case MAP:

                case VALUE:

                    p.buildChildElementUnmarshallers(chain,childUnmarshallers);

                    break;

                }

            }

        }

        this.frameSize = chain.getScopeSize();

        textHandler = childUnmarshallers.get(StructureLoaderBuilder.TEXT_HANDLER);

        catchAll = childUnmarshallers.get(StructureLoaderBuilder.CATCH_ALL);

        if(attWildcard!=null) {

            attCatchAll = (Accessor<Object,Map<QName,String>>) attWildcard;

            // we use attUnmarshallers==null as a sign to skip the attribute processing

            // altogether, so if we have an att wildcard we need to have an empty qname map.

            if(attUnmarshallers==null)

                attUnmarshallers = EMPTY;

        } else {

            attCatchAll = null;

        }

    }

    @Override

    public void startElement(UnmarshallingContext.State state, TagName ea) throws SAXException {

        UnmarshallingContext context = state.getContext();

        // create the object to unmarshal

        Object child;

        assert !beanInfo.isImmutable();

        // let's see if we can reuse the existing peer object

        child = context.getInnerPeer();

        if(child != null && beanInfo.jaxbType!=child.getClass())

            child = null;   // unexpected type.

        if(child != null)

            beanInfo.reset(child,context);

        if(child == null)

            child = context.createInstance(beanInfo);

        context.recordInnerPeer(child);

        state.target = child;

        fireBeforeUnmarshal(beanInfo, child, state);

        context.startScope(frameSize);

        if(attUnmarshallers!=null) {

            Attributes atts = ea.atts;

            for (int i = 0; i < atts.getLength(); i ++){

                String auri = atts.getURI(i);

                // may be empty string based on parser settings

                String alocal = atts.getLocalName(i);

                if ("".equals(alocal)) {

                    alocal = atts.getQName(i);

                }

                String avalue = atts.getValue(i);

                TransducedAccessor xacc = attUnmarshallers.get(auri, alocal);

                try {

                    if(xacc!=null) {

                        xacc.parse(child,avalue);

                    } else if (attCatchAll!=null) {

                        String qname = atts.getQName(i);

                        if(atts.getURI(i).equals(WellKnownNamespace.XML_SCHEMA_INSTANCE))

                            continue;   // xsi:* attributes are meant to be processed by us, not by user apps.

                        Object o = state.target;

                        Map<QName,String> map = attCatchAll.get(o);

                        if(map==null) {

                            // TODO: use  ClassFactory.inferImplClass(sig,knownImplClasses)

                            // if null, create a new map.

                            if(attCatchAll.valueType.isAssignableFrom(HashMap.class))

                                map = new HashMap<QName,String>();

                            else {

                                // we don't know how to create a map for this.

                                // report an error and back out

                                context.handleError(Messages.UNABLE_TO_CREATE_MAP.format(attCatchAll.valueType));

                                return;

                            }

                            attCatchAll.set(o,map);

                        }

                        String prefix;

                        int idx = qname.indexOf(':');

                        if(idx<0)   prefix="";

                        else        prefix=qname.substring(0,idx);

                        map.put(new QName(auri,alocal,prefix),avalue);

                    }

                } catch (AccessorException e) {

                   handleGenericException(e,true);

                }

            }

        }

    }

    @Override

    public void childElement(UnmarshallingContext.State state, TagName arg) throws SAXException {

        ChildLoader child = childUnmarshallers.get(arg.uri,arg.local);

        if(child==null) {

            if ((beanInfo != null) && (beanInfo.getTypeNames() != null)) {

                Iterator typeNamesIt = beanInfo.getTypeNames().iterator();

                QName parentQName = null;

                if ((typeNamesIt != null) && (typeNamesIt.hasNext()) && (catchAll == null)) {

                    parentQName = (QName) typeNamesIt.next();

                    String parentUri = parentQName.getNamespaceURI();

                    child = childUnmarshallers.get(parentUri, arg.local);

                }

            }

            if (child == null) {

                child = catchAll;

                if(child==null) {

                    super.childElement(state,arg);

                    return;

                }

            }

        }

        state.loader = child.loader;

        state.receiver = child.receiver;

    }

    @Override

    public Collection<QName> getExpectedChildElements() {

        return childUnmarshallers.keySet();

    }

    @Override

    public Collection<QName> getExpectedAttributes() {

        return attUnmarshallers.keySet();

    }

    @Override

    public void text(UnmarshallingContext.State state, CharSequence text) throws SAXException {

        if(textHandler!=null)

            textHandler.loader.text(state,text);

    }

    @Override

    public void leaveElement(UnmarshallingContext.State state, TagName ea) throws SAXException {

        state.getContext().endScope(frameSize);

        fireAfterUnmarshal(beanInfo, state.target, state.prev);

    }

    private static final QNameMap<TransducedAccessor> EMPTY = new QNameMap<TransducedAccessor>();

    public JaxBeanInfo getBeanInfo() {

        return beanInfo;

    }

}