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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package com.sun.xml.internal.ws.server;

import com.sun.xml.internal.ws.api.message.Packet;
import com.sun.xml.internal.ws.api.message.AttachmentSet;
import com.sun.xml.internal.ws.api.message.Attachment;

import java.util.*;
import javax.xml.ws.handler.MessageContext;
import javax.xml.ws.WebServiceContext;
import javax.activation.DataHandler;

Implements WebServiceContext's MessageContext on top of Packet. 
 This class creates a Map view for APPLICATION scoped properties that gets exposed to endpoint implementations during the invocation of web methods. The implementations access this map using WebServiceContext.getMessageContext(). 
 Some of the Map methods requre this class to build the complete Set of properties, but we try to avoid that as much as possible. 
Author:
Jitendra Kotamraju/**
 * Implements {@link WebServiceContext}'s {@link MessageContext} on top of {@link Packet}.
 *
 * <p>
 * This class creates a {@link Map} view for APPLICATION scoped properties that
 * gets exposed to endpoint implementations during the invocation
 * of web methods. The implementations access this map using
 * WebServiceContext.getMessageContext().
 *
 * <p>
 * Some of the {@link Map} methods requre this class to
 * build the complete {@link Set} of properties, but we
 * try to avoid that as much as possible.
 *
 *
 * @author Jitendra Kotamraju
 */
public final class EndpointMessageContextImpl extends AbstractMap<String,Object> implements MessageContext {

    
Lazily computed.
/**
     * Lazily computed.
     */
    private Set<Map.Entry<String,Object>> entrySet;
    private final Packet packet;

    
Params:
packet –  The Packet to wrap./**
     * @param packet
     *      The {@link Packet} to wrap.
     */
    public EndpointMessageContextImpl(Packet packet) {
        this.packet = packet;
    }

    @Override
    @SuppressWarnings("element-type-mismatch")
    public Object get(Object key) {
        if (packet.supports(key)) {
            return packet.get(key);    // strongly typed
        }
        if (packet.getHandlerScopePropertyNames(true).contains(key)) {
            return null;            // no such application-scope property
        }
        Object value =  packet.invocationProperties.get(key);

        //add the attachments from the Message to the corresponding attachment property
        if(key.equals(MessageContext.OUTBOUND_MESSAGE_ATTACHMENTS) ||
                key.equals(MessageContext.INBOUND_MESSAGE_ATTACHMENTS)){
            Map<String, DataHandler> atts = (Map<String, DataHandler>) value;
            if(atts == null)
                atts = new HashMap<String, DataHandler>();
            AttachmentSet attSet = packet.getMessage().getAttachments();
            for(Attachment att : attSet){
                atts.put(att.getContentId(), att.asDataHandler());
            }
            return atts;
        }
        return value;
    }

    @Override
    public Object put(String key, Object value) {
        if (packet.supports(key)) {
            return packet.put(key, value);     // strongly typed
        }
        Object old = packet.invocationProperties.get(key);
        if (old != null) {
            if (packet.getHandlerScopePropertyNames(true).contains(key)) {
                throw new IllegalArgumentException("Cannot overwrite property in HANDLER scope");
            }
            // Overwrite existing APPLICATION scoped property
            packet.invocationProperties.put(key, value);
            return old;
        }
        // No existing property. So Add a new property
        packet.invocationProperties.put(key, value);
        return null;
    }

    @Override
    @SuppressWarnings("element-type-mismatch")
    public Object remove(Object key) {
         if (packet.supports(key)) {
             return packet.remove(key);
        }
        Object old = packet.invocationProperties.get(key);
        if (old != null) {
            if (packet.getHandlerScopePropertyNames(true).contains(key)) {
                throw new IllegalArgumentException("Cannot remove property in HANDLER scope");
            }
            // Remove existing APPLICATION scoped property
            packet.invocationProperties.remove(key);
            return old;
        }
        // No existing property.
        return null;
    }

    public Set<Map.Entry<String, Object>> entrySet() {
        if (entrySet == null) {
            entrySet = new EntrySet();
        }
        return entrySet;
    }

    public void setScope(String name, MessageContext.Scope scope) {
        throw new UnsupportedOperationException(
                "All the properties in this context are in APPLICATION scope. Cannot do setScope().");
    }

    public MessageContext.Scope getScope(String name) {
        throw new UnsupportedOperationException(
                "All the properties in this context are in APPLICATION scope. Cannot do getScope().");
    }

    private class EntrySet extends AbstractSet<Map.Entry<String, Object>> {

        public Iterator<Map.Entry<String, Object>> iterator() {
            final Iterator<Map.Entry<String, Object>> it = createBackupMap().entrySet().iterator();

            return new Iterator<Map.Entry<String, Object>>() {
                Map.Entry<String, Object> cur;

                public boolean hasNext() {
                    return it.hasNext();
                }

                public Map.Entry<String, Object> next() {
                    cur = it.next();
                    return cur;
                }

                public void remove() {
                    it.remove();
                    EndpointMessageContextImpl.this.remove(cur.getKey());
                }
            };
        }

        public int size() {
            return createBackupMap().size();
        }

    }

    private Map<String, Object> createBackupMap() {
        Map<String, Object> backupMap = new HashMap<String, Object>();
        backupMap.putAll(packet.createMapView());
        Set<String> handlerProps = packet.getHandlerScopePropertyNames(true);
        for(Map.Entry<String, Object> e : packet.invocationProperties.entrySet()) {
            if (!handlerProps.contains(e.getKey())) {
                backupMap.put(e.getKey(), e.getValue());
            }
        }
        return backupMap;
    }

}