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 * reserved comment block
 * DO NOT REMOVE OR ALTER!
 */
/*
 * Copyright  1999-2004 The Apache Software Foundation.
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 */
package com.sun.org.apache.xml.internal.security.c14n.implementations;

import java.lang.reflect.Array;
import java.util.AbstractList;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;


import org.w3c.dom.Attr;
import org.w3c.dom.Node;


/**
 * A stack based Symble Table.
 *<br>For speed reasons all the symbols are introduced in the same map,
 * and at the same time in a list so it can be removed when the frame is pop back.
 * @author Raul Benito
 **/
public class NameSpaceSymbTable {

        /**The map betwen prefix-> entry table. */
        SymbMap symb = new SymbMap();
        /**The level of nameSpaces (for Inclusive visibility).*/
        int nameSpaces=0;
        /**The stacks for removing the definitions when doing pop.*/
        List level = new ArrayList();
    boolean cloned=true;
        static final String XMLNS="xmlns";
    /**
     * Default constractor
     **/
    public NameSpaceSymbTable() {
        //Insert the default binding for xmlns.
        NameSpaceSymbEntry ne=new NameSpaceSymbEntry("",null,true);
                ne.lastrendered="";
        symb.put(XMLNS,ne);
    }

    /**
         * Get all the unrendered nodes in the name space.
         * For Inclusive rendering
     * @param result the list where to fill the unrendered xmlns definitions.
         **/
        public  void getUnrenderedNodes(Collection result) {
           //List result=new ArrayList();
           Iterator it=symb.entrySet().iterator();
           while (it.hasNext()) {
                        NameSpaceSymbEntry n=(NameSpaceSymbEntry)(it.next());
                        //put them rendered?
                        if ((!n.rendered) && (n.n!=null)) {
                                result.add(n.n);
                                n.rendered=true;
                        }
           }
        }

        /**
     * Push a frame for visible namespace.
     * For Inclusive rendering.
     **/
        public void outputNodePush() {
                nameSpaces++;
                push();
        }

        /**
     * Pop a frame for visible namespace.
     **/
        public void outputNodePop() {
                nameSpaces--;
                pop();
        }

        /**
     * Push a frame for a node.
     * Inclusive or Exclusive.
     **/
        public void push() {
                //Put the number of namespace definitions in the stack.
        /**if (cloned) {
                Object ob[]= {symb,cloned ? symb : null};
                level.add(ob);
        } **/
        level.add(null);
        cloned=false;
        }

        /**
     * Pop a frame.
     * Inclusive or Exclusive.
     **/
        public void pop() {
        int size=level.size()-1;
        Object ob= level.remove(size);
        if (ob!=null) {
                symb=(SymbMap)ob;
            if (size==0) {
               cloned=false;
            } else
            cloned=(level.get(size-1)!=symb);
        } else {
                cloned=false;
        }


        }

        final void needsClone() {
                if (!cloned) {
            level.remove(level.size()-1);
            level.add(symb);
                        symb=(SymbMap) symb.clone();
            cloned=true;
        }
    }


        /**
         * Gets the attribute node that defines the binding for the prefix.
     * @param prefix the prefix to obtain the attribute.
     * @return null if there is no need to render the prefix. Otherwise the node of
     * definition.
     **/
        public Attr getMapping(String prefix) {
                NameSpaceSymbEntry entry=symb.get(prefix);
                if (entry==null) {
                        //There is no definition for the prefix(a bug?).
                        return null;
                }
                if (entry.rendered) {
                        //No need to render an entry already rendered.
                        return null;
                }
                // Mark this entry as render.
        entry=(NameSpaceSymbEntry) entry.clone();
        needsClone();
        symb.put(prefix,entry);
                entry.rendered=true;
                entry.level=nameSpaces;
                entry.lastrendered=entry.uri;
                // Return the node for outputing.
                return entry.n;
        }

        /**
     * Gets a definition without mark it as render.
     * For render in exclusive c14n the namespaces in the include prefixes.
     * @param prefix The prefix whose definition is neaded.
     * @return the attr to render, null if there is no need to render
     **/
        public Attr getMappingWithoutRendered(String prefix) {
                NameSpaceSymbEntry entry= symb.get(prefix);
                if (entry==null) {
                        return null;
                }
                if (entry.rendered) {
                        return null;
                }
                return entry.n;
        }

        /**
     * Adds the mapping for a prefix.
     * @param prefix the prefix of definition
     * @param uri the Uri of the definition
     * @param n the attribute that have the definition
     * @return true if there is already defined.
     **/
        public boolean addMapping(String prefix, String uri,Attr n) {
                NameSpaceSymbEntry ob = symb.get(prefix);
                if ((ob!=null) && uri.equals(ob.uri)) {
                        //If we have it previously defined. Don't keep working.
                        return false;
                }
                //Creates and entry in the table for this new definition.
                NameSpaceSymbEntry ne=new NameSpaceSymbEntry(uri,n,false);
        needsClone();
                symb.put(prefix, ne);
                if (ob != null) {
                        //We have a previous definition store it for the pop.
                        //Check if a previous definition(not the inmidiatly one) has been rendered.
                        ne.lastrendered=ob.lastrendered;
                        if ((ob.lastrendered!=null)&& (ob.lastrendered.equals(uri))) {
                                //Yes it is. Mark as rendered.
                                ne.rendered=true;
                        }
                }
        return true;
        }

    /**
     * Adds a definition and mark it as render.
     * For inclusive c14n.
     * @param prefix the prefix of definition
     * @param uri the Uri of the definition
     * @param n the attribute that have the definition
     * @return the attr to render, null if there is no need to render
     **/
    public Node addMappingAndRender(String prefix, String uri,Attr n) {
        NameSpaceSymbEntry ob = symb.get(prefix);

        if ((ob!=null) && uri.equals(ob.uri)) {
            if (!ob.rendered) {
                ob=(NameSpaceSymbEntry) ob.clone();
                needsClone();
                symb.put(prefix,ob);
                ob.lastrendered=uri;
                ob.rendered=true;
                return ob.n;
            }
            return null;
        }

        NameSpaceSymbEntry ne=new NameSpaceSymbEntry(uri,n,true);
        ne.lastrendered=uri;
        needsClone();
        symb.put(prefix, ne);
        if (ob != null) {

            if ((ob.lastrendered!=null)&& (ob.lastrendered.equals(uri))) {
                ne.rendered=true;
                return null;
            }
        }
        return ne.n;
    }
        /**
     * Adds & gets(if needed) the attribute node that defines the binding for the prefix.
     * Take on account if the rules of rendering in the inclusive c14n.
     * For inclusive c14n.
     * @param prefix the prefix to obtain the attribute.
     * @param outputNode the container element is an output element.
     * @param uri the Uri of the definition
     * @param n the attribute that have the definition
     * @return null if there is no need to render the prefix. Otherwise the node of
     * definition.
     **/
        public Node addMappingAndRenderXNodeSet(String prefix, String uri,Attr n,boolean outputNode) {
                NameSpaceSymbEntry ob = symb.get(prefix);
                int visibleNameSpaces=nameSpaces;
                if ((ob!=null) && uri.equals(ob.uri)) {
                        if (!ob.rendered) {
                                ob=(NameSpaceSymbEntry)ob.clone();
                needsClone();
                symb.put(prefix,ob);
                                ob.rendered=true;
                                ob.level=visibleNameSpaces;
                                return ob.n;
                        }
            ob=(NameSpaceSymbEntry)ob.clone();
            needsClone();
            symb.put(prefix,ob);
                        if (outputNode && (((visibleNameSpaces-ob.level)<2) || XMLNS.equals(prefix)) ) {
                                ob.level=visibleNameSpaces;
                                return null; //Already rendered, just return nulll
                        }
                        ob.level=visibleNameSpaces;
                        return ob.n;
                }

                NameSpaceSymbEntry ne=new NameSpaceSymbEntry(uri,n,true);
                ne.level=nameSpaces;
                ne.rendered=true;
        needsClone();
                symb.put(prefix, ne);
                if (ob != null) {
                        ne.lastrendered=ob.lastrendered;

                        if ((ob.lastrendered!=null)&& (ob.lastrendered.equals(uri))) {
                                ne.rendered=true;
                        }
                }
                return ne.n;
        }
}

/**
 * The internal structure of NameSpaceSymbTable.
 **/
class NameSpaceSymbEntry implements Cloneable {
    NameSpaceSymbEntry(String name,Attr n,boolean rendered) {
        this.uri=name;
        this.rendered=rendered;
        this.n=n;
    }
    /** @inheritDoc */
    public Object clone() {
        try {
            return super.clone();
        } catch (CloneNotSupportedException e) {
            return null;
        }
    }
    /** The level where the definition was rendered(Only for inclusive) */
    int level=0;
    /**The URI that the prefix defines */
    String uri;
    /**The last output in the URI for this prefix (This for speed reason).*/
    String lastrendered=null;
    /**This prefix-URI has been already render or not.*/
    boolean rendered=false;
    /**The attribute to include.*/
    Attr n;
};

class SymbMap implements Cloneable{
        int free=23;
        NameSpaceSymbEntry[] entries=new NameSpaceSymbEntry[free];
        String[] keys=new String[free];

        void put(String key, NameSpaceSymbEntry value) {
        int index = index(key);
                Object oldKey = keys[index];
                keys[index] = key;
                entries[index] = value;
        if (oldKey==null || !oldKey.equals(key)) {
                if (--free == 0) {
                                free=entries.length;
                    int newCapacity = free<<2;
                    rehash(newCapacity);
                }
        }
    }

    List entrySet() {
                List a=new ArrayList();
                for (int i=0;i<entries.length;i++) {
                        if ((entries[i]!=null) && !("".equals(entries[i]))) {
                                a.add(entries[i]);
                        }
                }
                return a;
        }


        protected int index(Object obj) {
        Object[] set = keys;
                int length = set.length;
                //abs of index
        int index = (obj.hashCode() & 0x7fffffff) %  length;
        Object cur = set[index];

        if (cur == null || (cur.equals( obj))) {
                        return index;
        }
        do {
                        index=index==length? 0:++index;
                        cur = set[index];
        } while (cur != null && (!cur.equals(obj)));
        return index;
    }
         /**
     * rehashes the map to the new capacity.
     *
     * @param newCapacity an <code>int</code> value
     */
    protected void rehash(int newCapacity) {
        int oldCapacity = keys.length;
        String oldKeys[] = keys;
                NameSpaceSymbEntry oldVals[] = entries;

                keys = new String[newCapacity];
                entries = new NameSpaceSymbEntry[newCapacity];

        for (int i = oldCapacity; i-- > 0;) {
            if(oldKeys[i] != null) {
                String o = oldKeys[i];
                int index = index(o);
                                keys[index] = o;
                                entries[index] = oldVals[i];
            }
        }
    }
         NameSpaceSymbEntry get(String key) {
                return  entries[index(key)];
            }
         protected Object clone()  {
                // TODO Auto-generated method stub
                try {
                        SymbMap copy=(SymbMap) super.clone();
                        copy.entries=new NameSpaceSymbEntry[entries.length];
                        System.arraycopy(entries,0,copy.entries,0,entries.length);
                        copy.keys=new String[keys.length];
                        System.arraycopy(keys,0,copy.keys,0,keys.length);

                        return copy;
                } catch (CloneNotSupportedException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                }
                return null;
        }
}