comment.java

来自「FuncPlotter is a combined Java applicati」· Java 代码 · 共 289 行

/*====================================================================*\

Comment.java

Comment class.

------------------------------------------------------------------------

This file is part of FuncPlotter, a combined Java application and applet
for plotting explicit functions in one variable.
Copyright 2005-2007 Andy Morgan-Richards.

FuncPlotter is free software: you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your
option) any later version.

This program 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 for more details.

You should have received a copy of the GNU General Public License along
with this program.  If not, see <http://www.gnu.org/licenses/>.

\*====================================================================*/


// PACKAGE


package xml;

//----------------------------------------------------------------------


// IMPORTS


import exception.AppException;

import java.io.IOException;

import java.util.ArrayList;
import java.util.List;

import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

//----------------------------------------------------------------------


// COMMENT CLASS


public class Comment
{

////////////////////////////////////////////////////////////////////////
//  Constants
////////////////////////////////////////////////////////////////////////

    private interface ElementName
    {
        String  COMMENT = "comment";
    }

    private interface AttrName
    {
        String  INDENT  = "indent";
    }

////////////////////////////////////////////////////////////////////////
//  Enumeration types
////////////////////////////////////////////////////////////////////////


    // ERROR IDENTIFIERS


    private enum ErrorId
        implements AppException.Id
    {

    ////////////////////////////////////////////////////////////////////
    //  Constants
    ////////////////////////////////////////////////////////////////////

        NO_ATTRIBUTE
        ( "The element does not have such an attribute." ),
        INVALID_ATTRIBUTE
        ( "The attribute is invalid." ),
        ATTRIBUTE_OUT_OF_BOUNDS
        ( "The attribute value is out of bounds." );

    ////////////////////////////////////////////////////////////////////
    //  Constructors
    ////////////////////////////////////////////////////////////////////

        private ErrorId( String message )
        {
            this.message = message;
        }

        //--------------------------------------------------------------

    ////////////////////////////////////////////////////////////////////
    //  Instance methods : AppException.Id interface
    ////////////////////////////////////////////////////////////////////

        public String getMessage( )
        {
            return message;
        }

        //--------------------------------------------------------------

    ////////////////////////////////////////////////////////////////////
    //  Instance variables
    ////////////////////////////////////////////////////////////////////

        private String  message;

    }

    //==================================================================

////////////////////////////////////////////////////////////////////////
//  Constructors
////////////////////////////////////////////////////////////////////////

    public Comment( )
    {
        text = new String( );
    }

    //------------------------------------------------------------------

    public Comment( String text )
    {
        setText( text );
    }

    //------------------------------------------------------------------

    public Comment( Element element )
        throws XmlParseException
    {

        String elementPath = XmlUtilities.getElementPath( element );

        // Attribute: indent

        String paramName = elementPath + "." + AttrName.INDENT;
        String paramValue = XmlUtilities.getAttribute( element, AttrName.INDENT );
        int indent = 0;
        if ( paramValue != null )
        {
            try
            {
                indent = Integer.parseInt( paramValue );
                if ( indent < 0 )
                    throw new XmlParseException( ErrorId.ATTRIBUTE_OUT_OF_BOUNDS, paramName, paramValue );
            }
            catch ( NumberFormatException e )
            {
                throw new XmlParseException( ErrorId.INVALID_ATTRIBUTE, paramName, paramValue );
            }
        }

        // Merge text nodes

        StringBuilder buffer = new StringBuilder( );
        NodeList nodes = element.getChildNodes( );
        for ( int i = 0; i < nodes.getLength( ); ++i )
        {
            if ( nodes.item( i ).getNodeType( ) == Node.TEXT_NODE )
                buffer.append( nodes.item( i ).getNodeValue( ) );
        }
        String str = buffer.toString( );

        // Remove indent from each line of comment

        buffer.setLength( 0 );
        int index = 0;
        while ( index < str.length( ) )
        {
            int startIndex = index;
            index = str.indexOf( '\n', index );
            if ( index < 0 )
                index = str.length( );

            int indentEndIndex = Math.min( startIndex + indent, index );
            while ( startIndex < indentEndIndex )
            {
                if ( str.charAt( startIndex ) != ' ' )
                    break;
                ++startIndex;
            }

            if ( index > startIndex )
                buffer.append( str.substring( startIndex, index ) );
            buffer.append( '\n' );
            ++index;
        }

        text = buffer.toString( ).trim( );

    }

    //------------------------------------------------------------------

////////////////////////////////////////////////////////////////////////
//  Class methods
////////////////////////////////////////////////////////////////////////

    public static String getElementName( )
    {
        return ElementName.COMMENT;
    }

    //------------------------------------------------------------------

////////////////////////////////////////////////////////////////////////
//  Instance methods
////////////////////////////////////////////////////////////////////////

    public String getText( )
    {
        return text;
    }

    //------------------------------------------------------------------

    public void setText( String text )
    {
        this.text = text.trim( );
    }

    //------------------------------------------------------------------

    public boolean isEmpty( )
    {
        return ( text.length( ) == 0 );
    }

    //------------------------------------------------------------------

    public void write( XmlWriter writer,
                       int       elementIndent,
                       int       textIndent )
        throws IOException
    {
        List<XmlWriter.Attribute> attributes = new ArrayList<XmlWriter.Attribute>( );
        attributes.add( new XmlWriter.Attribute( AttrName.INDENT, textIndent ) );
        writer.writeElementStart( ElementName.COMMENT, attributes, elementIndent, true, true );

        int index = 0;
        while ( index < text.length( ) )
        {
            int startIndex = index;
            index = text.indexOf( '\n', startIndex );
            if ( index < 0 )
                index = text.length( );
            if ( startIndex < index )
            {
                writer.writeSpaces( textIndent );
                writer.writeEscaped( text.substring( startIndex, index ) );
            }
            writer.writeLineSeparator( );
            ++index;
        }

        writer.writeElementEnd( ElementName.COMMENT, elementIndent );
    }

    //------------------------------------------------------------------

////////////////////////////////////////////////////////////////////////
//  Instance variables
////////////////////////////////////////////////////////////////////////

    private String  text;

}

//----------------------------------------------------------------------