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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

 * under the terms of the GNU General Public License version 2 only, as

 * 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,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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

import java.io.IOException;

import java.util.HashMap;

import java.util.LinkedHashMap;

import java.util.Map;

import java.util.TreeMap;

import java.util.Collection;

import java.util.Collections;

import java.util.Arrays;

import java.util.Set;

import javax.xml.stream.XMLStreamException;

import javax.xml.namespace.QName;

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

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

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

import com.sun.xml.internal.bind.v2.model.core.PropertyKind;

import com.sun.xml.internal.bind.v2.model.runtime.RuntimeMapPropertyInfo;

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.Name;

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

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

import com.sun.xml.internal.bind.v2.runtime.unmarshaller.ChildLoader;

import com.sun.xml.internal.bind.v2.runtime.unmarshaller.TagName;

import com.sun.xml.internal.bind.v2.runtime.unmarshaller.Loader;

import com.sun.xml.internal.bind.v2.runtime.unmarshaller.Receiver;

import com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallingContext;

import com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallingContext.State;

import org.xml.sax.SAXException;

/**

 * @author Kohsuke Kawaguchi

 */

final class SingleMapNodeProperty<BeanT,ValueT extends Map> extends PropertyImpl<BeanT> {

    private final Accessor<BeanT,ValueT> acc;

    /**

     * The tag name that surrounds the whole property.

     */

    private final Name tagName;

    /**

     * The tag name that corresponds to the 'entry' element.

     */

    private final Name entryTag;

    private final Name keyTag;

    private final Name valueTag;

    private final boolean nillable;

    private JaxBeanInfo keyBeanInfo;

    private JaxBeanInfo valueBeanInfo;

    /**

     * The implementation class for this property.

     * If the property is null, we create an instance of this class.

     */

    private final Class<? extends ValueT> mapImplClass;

    public SingleMapNodeProperty(JAXBContextImpl context, RuntimeMapPropertyInfo prop) {

        super(context, prop);

        acc = prop.getAccessor().optimize(context);

        this.tagName = context.nameBuilder.createElementName(prop.getXmlName());

        this.entryTag = context.nameBuilder.createElementName("","entry");

        this.keyTag = context.nameBuilder.createElementName("","key");

        this.valueTag = context.nameBuilder.createElementName("","value");

        this.nillable = prop.isCollectionNillable();

        this.keyBeanInfo = context.getOrCreate(prop.getKeyType());

        this.valueBeanInfo = context.getOrCreate(prop.getValueType());

        // infer the implementation class

        //noinspection unchecked

        Class<ValueT> sig = (Class<ValueT>) Utils.REFLECTION_NAVIGATOR.erasure(prop.getRawType());

        mapImplClass = ClassFactory.inferImplClass(sig,knownImplClasses);

        // TODO: error check for mapImplClass==null

        // what is the error reporting path for this part of the code?

    }

    private static final Class[] knownImplClasses = {

        HashMap.class, TreeMap.class, LinkedHashMap.class

    };

    public void reset(BeanT bean) throws AccessorException {

        acc.set(bean,null);

    }

    /**

     * A Map property can never be ID.

     */

    public String getIdValue(BeanT bean) {

        return null;

    }

    public PropertyKind getKind() {

        return PropertyKind.MAP;

    }

    public void buildChildElementUnmarshallers(UnmarshallerChain chain, QNameMap<ChildLoader> handlers) {

        keyLoader = keyBeanInfo.getLoader(chain.context,true);

        valueLoader = valueBeanInfo.getLoader(chain.context,true);

        handlers.put(tagName,new ChildLoader(itemsLoader,null));

    }

    private Loader keyLoader;

    private Loader valueLoader;

    /**

     * Handles <items> and </items>.

     *

     * The target will be set to a {@link Map}.

     */

    private final Loader itemsLoader = new Loader(false) {

        @Override

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

            // create or obtain the Map object

            try {

            } catch (AccessorException e) {

                // recover from error by setting a dummy Map that receives and discards the values

                handleGenericException(e,true);

                state.target = new HashMap();

            }

        }

        @Override

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

            super.leaveElement(state, ea);

            try {

            } catch (AccessorException ex) {

                handleGenericException(ex,true);

            }

        }

        @Override

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

            if(ea.matches(entryTag)) {

                state.loader = entryLoader;

            } else {

                super.childElement(state,ea);

            }

        }

        @Override

        public Collection<QName> getExpectedChildElements() {

            return Collections.singleton(entryTag.toQName());

        }

    };

    /**

     * Handles <entry> and </entry>.

     *

     * The target will be set to a {@link Map}.

     */

    private final Loader entryLoader = new Loader(false) {

        @Override

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

            state.target = new Object[2];  // this is inefficient

        }

        @Override

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

            Object[] keyValue = (Object[])state.target;

            Map map = (Map) state.prev.target;

            map.put(keyValue[0],keyValue[1]);

        }

        @Override

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

            if(ea.matches(keyTag)) {

                state.loader = keyLoader;

                state.receiver = keyReceiver;

                return;

            }

            if(ea.matches(valueTag)) {

                state.loader = valueLoader;

                state.receiver = valueReceiver;

                return;

            }

            super.childElement(state,ea);

        }

        @Override

        public Collection<QName> getExpectedChildElements() {

            return Arrays.asList(keyTag.toQName(),valueTag.toQName());

        }

    };

    private static final class ReceiverImpl implements Receiver {

        private final int index;

        public ReceiverImpl(int index) {

            this.index = index;

        }

        public void receive(UnmarshallingContext.State state, Object o) {

            ((Object[])state.target)[index] = o;

        }

    }

    private static final Receiver keyReceiver = new ReceiverImpl(0);

    private static final Receiver valueReceiver = new ReceiverImpl(1);

    @Override

    public void serializeBody(BeanT o, XMLSerializer w, Object outerPeer) throws SAXException, AccessorException, IOException, XMLStreamException {

        ValueT v = acc.get(o);

        if(v!=null) {

            bareStartTag(w,tagName,v);

            for( Map.Entry e : (Set<Map.Entry>)v.entrySet() ) {

                bareStartTag(w,entryTag,null);

                Object key = e.getKey();

                if(key!=null) {

                    w.startElement(keyTag,key);

                    w.childAsXsiType(key,fieldName,keyBeanInfo, false);

                    w.endElement();

                }

                Object value = e.getValue();

                if(value!=null) {

                    w.startElement(valueTag,value);

                    w.childAsXsiType(value,fieldName,valueBeanInfo, false);

                    w.endElement();

                }

                w.endElement();

            }

            w.endElement();

        } else

        if(nillable) {

            w.startElement(tagName,null);

            w.writeXsiNilTrue();

            w.endElement();

        }

    }

    private void bareStartTag(XMLSerializer w, Name tagName, Object peer) throws IOException, XMLStreamException, SAXException {

        w.startElement(tagName,peer);

        w.endNamespaceDecls(peer);

        w.endAttributes();

    }

    @Override

    public Accessor getElementPropertyAccessor(String nsUri, String localName) {

        if(tagName.equals(nsUri,localName))

            return acc;

        return null;

    }

}