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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.output;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Arrays;

import java.util.Collections;

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

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

import com.sun.istack.internal.FinalArrayList;

import com.sun.xml.internal.bind.marshaller.CharacterEscapeHandler;

/**

 * {@link XmlOutput} that generates canonical XML.

 *

 * @see com.sun.xml.internal.bind.api.C14nSupport_ArchitectureDocument

 * @author Kohsuke Kawaguchi

 */

public class C14nXmlOutput extends UTF8XmlOutput {

    public C14nXmlOutput(OutputStream out, Encoded[] localNames, boolean namedAttributesAreOrdered, CharacterEscapeHandler escapeHandler) {

        super(out, localNames, escapeHandler);

        this.namedAttributesAreOrdered = namedAttributesAreOrdered;

        for( int i=0; i<staticAttributes.length; i++ )

            staticAttributes[i] = new StaticAttribute();

    }

    /**

     * Hosts statically known attributes.

     *

     * {@link StaticAttribute} instances are reused.

     */

    private StaticAttribute[] staticAttributes = new StaticAttribute[8];

    private int len = 0;

    /**

     * Used to sort namespace declarations. Reused.

     */

    private int[] nsBuf = new int[8];

    /**

     * Hosts other attributes whose name are not statically known

     * (AKA attribute wildcard.)

     *

     * As long as this map is empty, there's no need for sorting.

     * see {@link com.sun.xml.internal.bind.api.C14nSupport_ArchitectureDocument} for more details.

     */

    private final FinalArrayList<DynamicAttribute> otherAttributes = new FinalArrayList<DynamicAttribute>();

    /**

     * True if {@link JAXBRIContext} is created with c14n support on,

     * in which case all named attributes are sorted by the marshaller

     * and we won't have to do it here.

     */

    private final boolean namedAttributesAreOrdered;

    final class StaticAttribute implements Comparable<StaticAttribute> {

        Name name;

        String value;

        public void set(Name name, String value) {

            this.name = name;

            this.value = value;

        }

        void write() throws IOException {

            C14nXmlOutput.super.attribute(name,value);

        }

        DynamicAttribute toDynamicAttribute() {

            int nsUriIndex = name.nsUriIndex;

            int prefix;

            if(nsUriIndex==-1)

                prefix = -1;

            else

                prefix = nsUriIndex2prefixIndex[nsUriIndex];

            return new DynamicAttribute(

                prefix, name.localName, value );

        }

        public int compareTo(StaticAttribute that) {

            return this.name.compareTo(that.name);

        }

    }

    final class DynamicAttribute implements Comparable<DynamicAttribute> {

        final int prefix;

        final String localName;

        final String value;

        public DynamicAttribute(int prefix, String localName, String value) {

            this.prefix = prefix;

            this.localName = localName;

            this.value = value;

        }

        private String getURI() {

            if(prefix==-1)  return "";

            else            return nsContext.getNamespaceURI(prefix);

        }

        public int compareTo(DynamicAttribute that) {

            int r = this.getURI().compareTo(that.getURI());

            if(r!=0)    return r;

            return this.localName.compareTo(that.localName);

        }

    }

    @Override

    public void attribute(Name name, String value) throws IOException {

        if(staticAttributes.length==len) {

            // reallocate

            int newLen = len*2;

            StaticAttribute[] newbuf = new StaticAttribute[newLen];

            System.arraycopy(staticAttributes,0,newbuf,0,len);

            for(int i=len;i<newLen;i++)

                staticAttributes[i] = new StaticAttribute();

            staticAttributes = newbuf;

        }

        staticAttributes[len++].set(name,value);

    }

    @Override

    public void attribute(int prefix, String localName, String value) throws IOException {

        otherAttributes.add(new DynamicAttribute(prefix,localName,value));

    }

    @Override

    public void endStartTag() throws IOException {

        if(otherAttributes.isEmpty()) {

            if(len!=0) {

                // sort is expensive even for size 0 array,

                // so it's worth checking len==0

                if(!namedAttributesAreOrdered)

                    Arrays.sort(staticAttributes,0,len);

                // this is the common case

                for( int i=0; i<len; i++ )

                    staticAttributes[i].write();

                len = 0;

            }

        } else {

            // this is the exceptional case

            // sort all the attributes, not just the other attributes

            for( int i=0; i<len; i++ )

                otherAttributes.add(staticAttributes[i].toDynamicAttribute());

            len = 0;

            Collections.sort(otherAttributes);

            // write them all

            int size = otherAttributes.size();

            for( int i=0; i<size; i++ ) {

                DynamicAttribute a = otherAttributes.get(i);

                super.attribute(a.prefix,a.localName,a.value);

            }

            otherAttributes.clear();

        }

        super.endStartTag();

    }

    /**

     * Write namespace declarations after sorting them.

     */

    @Override

    protected void writeNsDecls(int base) throws IOException {

        int count = nsContext.getCurrent().count();

        if(count==0)

            return; // quickly reject the most common case

        if(count>nsBuf.length)

            nsBuf = new int[count];

        for( int i=count-1; i>=0; i-- )

            nsBuf[i] = base+i;

        // do a bubble sort. Hopefully # of ns decls are small enough to justify bubble sort.

        // faster algorithm is more compliated to implement

        for( int i=0; i<count; i++ ) {

            for( int j=i+1; j<count; j++ ) {

                String p = nsContext.getPrefix(nsBuf[i]);

                String q = nsContext.getPrefix(nsBuf[j]);

                if( p.compareTo(q) > 0 ) {

                    // swap

                    int t = nsBuf[j];

                    nsBuf[j] = nsBuf[i];

                    nsBuf[i] = t;

                }

            }

        }

        // write them out

        for( int i=0; i<count; i++ )

            writeNsDecl(nsBuf[i]);

    }

}