list.java

iText是一个能够快速产生PDF文件的java类库。iText的java类对于那些要产生包含文本

/*
 * $Id: List.java 2744 2007-05-09 22:51:47Z xlv $
 * $Name$
 *
 * Copyright 1999, 2000, 2001, 2002 by Bruno Lowagie.
 *
 * The contents of this file are subject to the Mozilla Public License Version 1.1
 * (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.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the License.
 *
 * The Original Code is 'iText, a free JAVA-PDF library'.
 *
 * The Initial Developer of the Original Code is Bruno Lowagie. Portions created by
 * the Initial Developer are Copyright (C) 1999, 2000, 2001, 2002 by Bruno Lowagie.
 * All Rights Reserved.
 * Co-Developer of the code is Paulo Soares. Portions created by the Co-Developer
 * are Copyright (C) 2000, 2001, 2002 by Paulo Soares. All Rights Reserved.
 *
 * Contributor(s): all the names of the contributors are added in the source code
 * where applicable.
 *
 * Alternatively, the contents of this file may be used under the terms of the
 * LGPL license (the "GNU LIBRARY GENERAL PUBLIC LICENSE"), in which case the
 * provisions of LGPL are applicable instead of those above.  If you wish to
 * allow use of your version of this file only under the terms of the LGPL
 * License and not to allow others to use your version of this file under
 * the MPL, indicate your decision by deleting the provisions above and
 * replace them with the notice and other provisions required by the LGPL.
 * If you do not delete the provisions above, a recipient may use your version
 * of this file under either the MPL or the GNU LIBRARY GENERAL PUBLIC LICENSE.
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the MPL as stated above or under the terms of the GNU
 * Library General Public License as published by the Free Software Foundation;
 * either version 2 of the License, or any later version.
 *
 * This library 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 Library general Public License for more
 * details.
 *
 * If you didn't download this code from the following link, you should check if
 * you aren't using an obsolete version:
 * http://www.lowagie.com/iText/
 */

package com.lowagie.text;

import java.util.ArrayList;
import java.util.Iterator;

import com.lowagie.text.factories.RomanAlphabetFactory;

/**
 * A <CODE>List</CODE> contains several <CODE>ListItem</CODE>s.
 * <P>
 * <B>Example 1:</B>
 * <BLOCKQUOTE><PRE>
 * <STRONG>List list = new List(true, 20);</STRONG>
 * <STRONG>list.add(new ListItem("First line"));</STRONG>
 * <STRONG>list.add(new ListItem("The second line is longer to see what happens once the end of the line is reached. Will it start on a new line?"));</STRONG>
 * <STRONG>list.add(new ListItem("Third line"));</STRONG>
 * </PRE></BLOCKQUOTE>
 *
 * The result of this code looks like this:
 *	<OL>
 *		<LI>
 *			First line
 *		</LI>
 *		<LI>
 *			The second line is longer to see what happens once the end of the line is reached. Will it start on a new line?
 *		</LI>
 *		<LI>
 *			Third line
 *		</LI>
 *	</OL>
 *
 * <B>Example 2:</B>
 * <BLOCKQUOTE><PRE>
 * <STRONG>List overview = new List(false, 10);</STRONG>
 * <STRONG>overview.add(new ListItem("This is an item"));</STRONG>
 * <STRONG>overview.add("This is another item");</STRONG>
 * </PRE></BLOCKQUOTE>
 *
 * The result of this code looks like this:
 *	<UL>
 *		<LI>
 *			This is an item
 *		</LI>
 *		<LI>
 *			This is another item
 *		</LI>
 *	</UL>
 *
 * @see		Element
 * @see		ListItem
 */

public class List implements TextElementArray {
    
    // constants
	
	/** a possible value for the numbered parameter */
	public static final boolean ORDERED = true;
	/** a possible value for the numbered parameter */
	public static final boolean UNORDERED = false;
	/** a possible value for the lettered parameter */
	public static final boolean NUMERICAL = false;
	/** a possible value for the lettered parameter */
	public static final boolean ALPHABETICAL = true;
	/** a possible value for the lettered parameter */
	public static final boolean UPPERCASE = false;
	/** a possible value for the lettered parameter */
	public static final boolean LOWERCASE = true;
	
    // member variables
	
	/** This is the <CODE>ArrayList</CODE> containing the different <CODE>ListItem</CODE>s. */
    protected ArrayList list = new ArrayList();
    
    /** Indicates if the list has to be numbered. */
    protected boolean numbered = false;
    /** Indicates if the listsymbols are numerical or alphabetical. */
    protected boolean lettered = false;
    /** Indicates if the listsymbols are lowercase or uppercase. */
    protected boolean lowercase = false;
    /** Indicates if the indentation has to be set automatically. */
    protected boolean autoindent = false;
    /** Indicates if the indentation of all the items has to be aligned. */
    protected boolean alignindent = false;
    
    /** This variable indicates the first number of a numbered list. */
    protected int first = 1;
    /** This is the listsymbol of a list that is not numbered. */
    protected Chunk symbol = new Chunk("- ");
    
    /** The indentation of this list on the left side. */
    protected float indentationLeft = 0;
    /** The indentation of this list on the right side. */
    protected float indentationRight = 0;
    /** The indentation of the listitems. */
    protected float symbolIndent = 0;
    
    // constructors

    /** Constructs a <CODE>List</CODE>. */
    public List() {
        this(false, false);
    }
    
    /**
     * Constructs a <CODE>List</CODE>.
     * @param	numbered		a boolean
     */
    public List(boolean numbered) {
      	this(numbered, false);
    }
        
    /**
     * Constructs a <CODE>List</CODE>.
     * @param	numbered		a boolean
     * @param lettered has the list to be 'numbered' with letters
     */
    public List(boolean numbered, boolean lettered) {
    	this.numbered = numbered;
        this.lettered = lettered;
        this.autoindent = true;
        this.alignindent = true;
    }
    
    /**
     * Constructs a <CODE>List</CODE>.
     * <P>
     * Remark: the parameter <VAR>symbolIndent</VAR> is important for instance when
     * generating PDF-documents; it indicates the indentation of the listsymbol.
     * It is not important for HTML-documents.
     *
     * @param	numbered		a boolean
     * @param	symbolIndent	the indentation that has to be used for the listsymbol
     */
    public List(boolean numbered, float symbolIndent) {
        this(numbered, false, symbolIndent);
    }
    
    /**
     * Creates a list
     * @param numbered has the list to be numbered?
     * @param lettered has the list to be 'numbered' with letters
     * @param symbolIndent the indentation of the symbol
     */
    public List(boolean numbered, boolean lettered, float symbolIndent) {
        this.numbered = numbered;
        this.lettered = lettered;
        this.symbolIndent = symbolIndent;
    }
    
    // implementation of the Element-methods
    
    /**
     * Processes the element by adding it (or the different parts) to an
     * <CODE>ElementListener</CODE>.
     *
     * @param	listener	an <CODE>ElementListener</CODE>
     * @return	<CODE>true</CODE> if the element was processed successfully
     */
    public boolean process(ElementListener listener) {
        try {
            for (Iterator i = list.iterator(); i.hasNext(); ) {
                listener.add((Element) i.next());
            }
            return true;
        }
        catch(DocumentException de) {
            return false;
        }
    }
    
    /**
     * Gets the type of the text element.
     *
     * @return	a type
     */
    public int type() {
        return Element.LIST;
    }
    
    /**
     * Gets all the chunks in this element.
     *
     * @return	an <CODE>ArrayList</CODE>
     */
    public ArrayList getChunks() {
        ArrayList tmp = new ArrayList();
        for (Iterator i = list.iterator(); i.hasNext(); ) {
            tmp.addAll(((Element) i.next()).getChunks());
        }
        return tmp;
    }
    
    // methods to set the membervariables
    
    /**
     * Adds an <CODE>Object</CODE> to the <CODE>List</CODE>.
     *
     * @param	o		the object to add.
     * @return true if adding the object succeeded
     */
    public boolean add(Object o) {
        if (o instanceof ListItem) {
            ListItem item = (ListItem) o;
            if (numbered || lettered) {
                Chunk chunk;
                int index = first + list.size();
                if ( lettered )
                    chunk = new Chunk(RomanAlphabetFactory.getString(index, lowercase), symbol.getFont());
                else
                    chunk = new Chunk(String.valueOf(index), symbol.getFont());
                chunk.append(". ");
                item.setListSymbol(chunk);
            }
            else {
                item.setListSymbol(symbol);
            }
            item.setIndentationLeft(symbolIndent, autoindent);
            item.setIndentationRight(0);
            list.add(item);
        }
        else if (o instanceof List) {
            List nested = (List) o;
            nested.setIndentationLeft(nested.getIndentationLeft() + symbolIndent);
            first--;
            return list.add(nested);
        }
        else if (o instanceof String) {
            return this.add(new ListItem((String) o));
        }
        return false;
    }
    
    // extra methods
	
	/** Makes sure all the items in the list have the same indentation. */
    public void normalizeIndentation() {
        float max = 0;
    	Element o;
        for (Iterator i = list.iterator(); i.hasNext(); ) {
        	o = (Element)i.next();
            if (o instanceof ListItem) {
            	max = Math.max(max, ((ListItem)o).getIndentationLeft());
            }
        }
        for (Iterator i = list.iterator(); i.hasNext(); ) {
        	o = (Element)i.next();
            if (o instanceof ListItem) {
            	((ListItem)o).setIndentationLeft(max);
            }