Java tutorial
/* * $Id: Row.java 3373 2008-05-12 16:21:24Z xlv $ * * 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; /** * A <CODE>Row</CODE> is part of a <CODE>Table</CODE> * and contains some <CODE>Cells</CODE>. * <P> * All <CODE>Row</CODE>s are constructed by a <CODE>Table</CODE>-object. * You don't have to construct any <CODE>Row</CODE> yourself. * In fact you can't construct a <CODE>Row</CODE> outside the package. * <P> * Since a <CODE>Cell</CODE> can span several rows and/or columns * a row can contain reserved space without any content. * * @see Element * @see Cell * @see Table */ public class Row implements Element { // constants /** id of a null element in a Row*/ public static final int NULL = 0; /** id of the Cell element in a Row*/ public static final int CELL = 1; /** id of the Table element in a Row*/ public static final int TABLE = 2; // member variables /** This is the number of columns in the <CODE>Row</CODE>. */ protected int columns; /** This is a valid position the <CODE>Row</CODE>. */ protected int currentColumn; /** This is the array that keeps track of reserved cells. */ protected boolean[] reserved; /** This is the array of Objects (<CODE>Cell</CODE> or <CODE>Table</CODE>). */ protected Object[] cells; /** This is the vertical alignment. */ protected int horizontalAlignment; // constructors /** * Constructs a <CODE>Row</CODE> with a certain number of <VAR>columns</VAR>. * * @param columns a number of columns */ protected Row(int columns) { this.columns = columns; reserved = new boolean[columns]; cells = new Object[columns]; currentColumn = 0; } // implementation of the Element-methods /** * Processes the element by adding it (or the different parts) to a * <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 { return listener.add(this); } catch (DocumentException de) { return false; } } /** * Gets the type of the text element. * * @return a type */ public int type() { return Element.ROW; } /** * Gets all the chunks in this element. * * @return an <CODE>ArrayList</CODE> */ public ArrayList getChunks() { return new ArrayList(); } /** * @see com.lowagie.text.Element#isContent() * @since iText 2.0.8 */ public boolean isContent() { return true; } /** * @see com.lowagie.text.Element#isNestable() * @since iText 2.0.8 */ public boolean isNestable() { return false; } // method to delete a column /** * Returns a <CODE>Row</CODE> that is a copy of this <CODE>Row</CODE> * in which a certain column has been deleted. * * @param column the number of the column to delete */ void deleteColumn(int column) { if ((column >= columns) || (column < 0)) { throw new IndexOutOfBoundsException("getCell at illegal index : " + column); } columns--; boolean newReserved[] = new boolean[columns]; Object newCells[] = new Cell[columns]; for (int i = 0; i < column; i++) { newReserved[i] = reserved[i]; newCells[i] = cells[i]; if (newCells[i] != null && (i + ((Cell) newCells[i]).getColspan() > column)) { ((Cell) newCells[i]).setColspan(((Cell) cells[i]).getColspan() - 1); } } for (int i = column; i < columns; i++) { newReserved[i] = reserved[i + 1]; newCells[i] = cells[i + 1]; } if (cells[column] != null && ((Cell) cells[column]).getColspan() > 1) { newCells[column] = cells[column]; ((Cell) newCells[column]).setColspan(((Cell) newCells[column]).getColspan() - 1); } reserved = newReserved; cells = newCells; } // methods /** * Adds a <CODE>Cell</CODE> to the <CODE>Row</CODE>. * * @param element the element to add (currently only Cells and Tables supported) * @return the column position the <CODE>Cell</CODE> was added, * or <CODE>-1</CODE> if the <CODE>element</CODE> couldn't be added. */ int addElement(Object element) { return addElement(element, currentColumn); } /** * Adds an element to the <CODE>Row</CODE> at the position given. * * @param element the element to add. (currently only Cells and Tables supported * @param column the position where to add the cell. * @return the column position the <CODE>Cell</CODE> was added, * or <CODE>-1</CODE> if the <CODE>Cell</CODE> couldn't be added. */ int addElement(Object element, int column) { if (element == null) throw new NullPointerException("addCell - null argument"); if ((column < 0) || (column > columns)) throw new IndexOutOfBoundsException("addCell - illegal column argument"); if (!((getObjectID(element) == CELL) || (getObjectID(element) == TABLE))) throw new IllegalArgumentException("addCell - only Cells or Tables allowed"); int lColspan = ((Cell.class.isInstance(element)) ? ((Cell) element).getColspan() : 1); if (!reserve(column, lColspan)) { return -1; } cells[column] = element; currentColumn += lColspan - 1; return column; } /** * Puts <CODE>Cell</CODE> to the <CODE>Row</CODE> at the position given, doesn't reserve colspan. * * @param aElement the cell to add. * @param column the position where to add the cell. */ void setElement(Object aElement, int column) { if (reserved[column]) throw new IllegalArgumentException("setElement - position already taken"); cells[column] = aElement; if (aElement != null) { reserved[column] = true; } } /** * Reserves a <CODE>Cell</CODE> in the <CODE>Row</CODE>. * * @param column the column that has to be reserved. * @return <CODE>true</CODE> if the column was reserved, <CODE>false</CODE> if not. */ boolean reserve(int column) { return reserve(column, 1); } /** * Reserves a <CODE>Cell</CODE> in the <CODE>Row</CODE>. * * @param column the column that has to be reserved. * @param size the number of columns * @return <CODE>true</CODE> if the column was reserved, <CODE>false</CODE> if not. */ boolean reserve(int column, int size) { if ((column < 0) || ((column + size) > columns)) throw new IndexOutOfBoundsException("reserve - incorrect column/size"); for (int i = column; i < column + size; i++) { if (reserved[i]) { // undo reserve for (int j = i; j >= column; j--) { reserved[j] = false; } return false; } reserved[i] = true; } return true; } // methods to retrieve information /** * Returns true/false when this position in the <CODE>Row</CODE> has been reserved, either filled or through a colspan of an Element. * * @param column the column. * @return <CODE>true</CODE> if the column was reserved, <CODE>false</CODE> if not. */ boolean isReserved(int column) { return reserved[column]; } /** * Returns the type-id of the element in a Row. * * @param column the column of which you'd like to know the type * @return the type-id of the element in the row */ int getElementID(int column) { if (cells[column] == null) return NULL; else if (Cell.class.isInstance(cells[column])) return CELL; else if (Table.class.isInstance(cells[column])) return TABLE; return -1; } /** * Returns the type-id of an Object. * * @param element the object of which you'd like to know the type-id, -1 if invalid * @return the type-id of an object */ int getObjectID(Object element) { if (element == null) return NULL; else if (Cell.class.isInstance(element)) return CELL; else if (Table.class.isInstance(element)) return TABLE; return -1; } /** * Gets a <CODE>Cell</CODE> or <CODE>Table</CODE> from a certain column. * * @param column the column the <CODE>Cell/Table</CODE> is in. * @return the <CODE>Cell</CODE>,<CODE>Table</CODE> or <VAR>Object</VAR> if the column was * reserved or null if empty. */ public Object getCell(int column) { if ((column < 0) || (column > columns)) { throw new IndexOutOfBoundsException("getCell at illegal index :" + column + " max is " + columns); } return cells[column]; } /** * Checks if the row is empty. * * @return <CODE>true</CODE> if none of the columns is reserved. */ public boolean isEmpty() { for (int i = 0; i < columns; i++) { if (cells[i] != null) { return false; } } return true; } /** * Gets the number of columns. * * @return a value */ public int getColumns() { return columns; } /** * Sets the horizontal alignment. * * @param value the new value */ public void setHorizontalAlignment(int value) { horizontalAlignment = value; } /** * Gets the horizontal alignment. * * @return a value */ public int getHorizontalAlignment() { return horizontalAlignment; } }