From 0db6721bd0aae195872f71bc58c4a3a3e3a5b61d Mon Sep 17 00:00:00 2001 From: Mark Beardsley Date: Fri, 7 Aug 2009 15:36:35 +0000 Subject: [PATCH] New HSSF example. git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@802052 13f79535-47bb-0310-9956-ffa450edef68 --- .../examples/AddDimensionedImage.java | 926 ++++++++++++++++++ 1 file changed, 926 insertions(+) create mode 100644 src/examples/src/org/apache/poi/hssf/usermodel/examples/AddDimensionedImage.java diff --git a/src/examples/src/org/apache/poi/hssf/usermodel/examples/AddDimensionedImage.java b/src/examples/src/org/apache/poi/hssf/usermodel/examples/AddDimensionedImage.java new file mode 100644 index 0000000000..b16fe41f16 --- /dev/null +++ b/src/examples/src/org/apache/poi/hssf/usermodel/examples/AddDimensionedImage.java @@ -0,0 +1,926 @@ +/* ==================================================================== + Licensed to the Apache Software Foundation (ASF) under one or more + contributor license agreements. See the NOTICE file distributed with + this work for additional information regarding copyright ownership. + The ASF licenses this file to You 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 org.apache.poi.hssf.usermodel.examples; + +import java.io.File; +import java.io.FileInputStream; +import java.io.FileOutputStream; +import java.io.ByteArrayOutputStream; +import java.io.FileNotFoundException; +import java.io.IOException; + +import org.apache.poi.hssf.usermodel.HSSFWorkbook; +import org.apache.poi.hssf.usermodel.HSSFSheet; +import org.apache.poi.hssf.usermodel.HSSFRow; +import org.apache.poi.hssf.usermodel.HSSFClientAnchor; +import org.apache.poi.hssf.usermodel.HSSFPatriarch; +import org.apache.poi.hssf.util.CellReference; + + +/** + * Demonstrates how to add an image to a worksheet and set that image's size + * to a specific number of milimetres irrespective of the width of the columns + * or height of the rows. Overridden methods are provided so that the location + * of the image - the cells row and column co-ordinates that define the top + * left hand corners of the image - can be identified either in the familiar + * Excel manner - A1 for instance - or using POI's methodolody of a column and + * row index where 0, 0 would indicate cell A1. + * + * The best way to make use of these techniques is to delay adding the image to + * the sheet until all other work has been completed. That way, the sizes of + * all rows and columns will have been adjusted - assuming that step was + * necessary. Even though the anchors type is set to prevent the image moving + * or re-sizing, this setting does not have any effect until the sheet is being + * viewed using the Excel application. + * + * The key to the process is the HSSFClientAnchor class. It accepts eight + * parameters that define, in order; + * + * * How far - in terms of co-ordinate position - the image should be inset + * from the left hand border of a cell. + * * How far - in terms of co-ordinate positions - the image should be inset + * from the from the top of the cell. + * * How far - in terms of co-ordinate positions - the right hand edge of + * the image should protrude into a cell (measured from the cell's left hand + * edge to the image's right hand edge). + * * How far - in terms of co-ordinate positions - the bottm edge of the + * image should protrude into a row (measured from the cell's top edge to + * the image's bottom edge). + * * The index of the column that contains the cell whose top left hand + * corner should be aligned with the top left hand corner of the image. + * * The index of the row that contains the cell whose top left hand corner + * should be aligned with the image's top left hand corner. + * * The index of the column that contains the cell whose top left hand + * corner should be aligned with the image's bottom right hand corner + * * The index number of the row that contains the cell whose top left + * hand corner should be aligned with the images bottom right hand corner. + * + * It can be used to add an image into cell A1, for example, in the following + * manner; + * + * HSSFClientAnchor anchor = new HSSFClientAnchor(0, 0, 0, 0, + * (short)0, 0, (short)1, 1); + * + * The final four parameters determine that the top left hand corner should be + * aligned with the top left hand corner of cell A1 and it's bottom right + * hand corner with the top left hand corner of cell B2. Think of the image as + * being stretched so that it's top left hand corner is aligned with the top + * left hand corner of cell A1 and it's bottom right hand corner is aligned with + * the top left hand corner of cell B1. Interestingly, this would also produce + * the same results; + * + * anchor = new HSSFClientAnchor(0, 0, 1023, 255, + * (short)0, 0, (short)0, 0); + * + * Note that the final four parameters all contain the same value and seem to + * indicate that the images top left hand corner is aligned with the top left + * hand corner of cell A1 and that it's bottom right hand corner is also + * aligned with the top left hand corner of cell A1. Yet, running this code + * would see the image fully occupying cell A1. That is the result of the + * values passed to parameters three and four; these I have referred to as + * determing the images co-ordinates within the cell. They indicate that the + * image should occupy - in order - the full width of the column and the full + * height of the row. + * + * The co-ordinate values shown are the maxima; and they are independent of + * row height/column width and of the font used. Passing 255 will always result + * in the image occupying the full height of the row and passing 1023 will + * always result in the image occupying the full width of the column. They help + * in situations where an image is larger than a column/row and must overlap + * into the next column/row. Using them does mean, however, that it is often + * necessary to perform conversions between Excel's characters units, points, + * pixels and millimetres in order to establish how many rows/columns an image + * should occupy and just what the varous insets ought to be. + * + * Note that the first two parameters of the HSSFClientAchor classes constructor + * are not made use of in the code that follows. It would be fairly trivial + * however to extend these example further and provide methods that would centre + * an image within a cell or allow the user to specify that a plain border a + * fixed number of millimetres wide should wrap around the image. Those first + * two parameters would make this sort of functionality perfectly possible. + * + * Owing to the various conversions used, the actual size of the image may vary + * from that required; testing has so far found this to be in the region of + * plus or minus two millimetres. Most likely by modifying the way the + * calculations are performed - possibly using double(s) throughout and + * rounding the values at the correct point - it is likely that these errors + * could be reduced or removed. + * + * @author Mark Beardsley [msb at apache.org] + * @version 1.00 5th August 2009. + */ +public class AddDimensionedImage { + + // Four constants that determine how - and indeed whether - the rows + // and columns an image may overlie should be expanded to accomodate that + // image. + // Passing EXPAND_ROW will result in the height of a row being increased + // to accomodate the image if it is not already larger. The image will + // be layed across one or more columns. + // Passing EXPAND_COLUMN will result in the width of the column being + // increased to accomodate the image if it is not already larger. The image + // will be layed across one or many rows. + // Passing EXPAND_ROW_AND_COLUMN will result in the height of the row + // bing increased along with the width of the column to accomdate the + // image if either is not already larger. + // Passing OVERLAY_ROW_AND_COLUMN will result in the image being layed + // over one or more rows and columns. No row or column will be resized, + // instead, code will determine how many rows and columns the image should + // overlie. + public static final int EXPAND_ROW = 1; + public static final int EXPAND_COLUMN = 2; + public static final int EXPAND_ROW_AND_COLUMN = 3; + public static final int OVERLAY_ROW_AND_COLUMN = 7; + + /** + * Add an image to a worksheet. + * + * @param cellNumber A String that contains the location of the cell whose + * top left hand corner should be aligned with the top + * left hand corner of the image; for example "A1", "A2" + * etc. This is to support the familiar Excel syntax. + * Whilst images are are not actually inserted into cells + * this provides a convenient method of indicating where + * the image should be positioned on the sheet. + * @param sheet A reference to the sheet that contains the cell referenced + * above. + * @param imageFile A String that encapsulates the name of and path to + * the image that is to be 'inserted into' the sheet. + * @param reqImageWidthMM A primitive double that contains the required + * width of the image in millimetres. + * @param reqImageHeightMM A primitive double that contains the required + * height of the image in millimetres. + * @param resizeBehaviour A primitive int whose value will determine how + * the code should react if the image is larger than + * the cell referenced by the cellNumber parameter. + * Four constants are provided to determine what + * should happen; + * AddDimensionedImage.EXPAND_ROW + * AddDimensionedImage.EXPAND_COLUMN + * AddDimensionedImage.EXPAND_ROW_AND_COLUMN + * AddDimensionedImage.OVERLAY_ROW_AND_COLUMN + * @throws java.io.FileNotFoundException If the file containing the image + * cannot be located. + * @throws java.io.IOException If a problem occurs whilst reading the file + * of image data. + * @throws java.lang.IllegalArgumentException If an invalid value is passed + * to the resizeBehaviour + * parameter. + */ + public void addImageToSheet(String cellNumber, HSSFSheet sheet, + String imageFile, double reqImageWidthMM, double reqImageHeightMM, + int resizeBehaviour) throws FileNotFoundException, IOException, + IllegalArgumentException { + // Convert the String into column and row indices then chain the + // call to the overridden addImageToSheet() method. + CellReference cellRef = new CellReference(cellNumber); + this.addImageToSheet(cellRef.getCol(), cellRef.getRow(), sheet, + imageFile, reqImageWidthMM, reqImageHeightMM,resizeBehaviour); + } + + /** + * Add an image to a worksheet. + * + * @param colNumber A primitive int that contains the index number of a + * column on the worksheet; POI column indices are zero + * based. Together with the rowNumber parameter's value, + * this parameter identifies a cell on the worksheet. The + * image's top left hand corner will be aligned with the + * top left hand corner of this cell. + * @param rowNumber A primtive int that contains the index number of a row + * on the worksheet; POI row indices are zero based. + * Together with the rowNumber parameter's value, this + * parameter identifies a cell on the worksheet. The + * image's top left hand corner will be aligned with the + * top left hand corner of this cell. + * @param sheet A reference to the sheet that contains the cell identified + * by the two parameters above. + * @param imageFile A String that encapsulates the name of and path to + * the image that is to be 'inserted into' the sheet. + * @param reqImageWidthMM A primitive double that contains the required + * width of the image in millimetres. + * @param reqImageHeightMM A primitive double that contains the required + * height of the image in millimetres. + * @param resizeBehaviour A primitive int whose value will determine how + * the code should react if the image is larger than + * the cell referenced by the colNumber and + * rowNumber parameters. Four constants are provided + * to determine what should happen; + * AddDimensionedImage.EXPAND_ROW + * AddDimensionedImage.EXPAND_COLUMN + * AddDimensionedImage.EXPAND_ROW_AND_COLUMN + * AddDimensionedImage.OVERLAY_ROW_AND_COLUMN + * @throws java.io.FileNotFoundException If the file containing the image + * cannot be located. + * @throws java.io.IOException If a problem occurs whilst reading the file + * of image data. + * @throws java.lang.IllegalArgumentException If an invalid value is passed + * to the resizeBehaviour + * parameter. + */ + private void addImageToSheet(int colNumber, int rowNumber, HSSFSheet sheet, + String imageFile, double reqImageWidthMM, double reqImageHeightMM, + int resizeBehaviour) throws FileNotFoundException, IOException, + IllegalArgumentException { + HSSFRow row = null; + HSSFClientAnchor anchor = null; + HSSFPatriarch patriarch = null; + ClientAnchorDetail rowClientAnchorDetail = null; + ClientAnchorDetail colClientAnchorDetail = null; + + // Validate the resizeBehaviour parameter. + if((resizeBehaviour != AddDimensionedImage.EXPAND_COLUMN) && + (resizeBehaviour != AddDimensionedImage.EXPAND_ROW) && + (resizeBehaviour != AddDimensionedImage.EXPAND_ROW_AND_COLUMN) && + (resizeBehaviour != AddDimensionedImage.OVERLAY_ROW_AND_COLUMN)) { + throw new IllegalArgumentException("Invalid value passed to the " + + "resizeBehaviour parameter of AddDimensionedImage.addImageToSheet()"); + } + + // Call methods to calculate how the image and sheet should be + // manipulated to accomodate the image; columns and then rows. + colClientAnchorDetail = this.fitImageToColumns(sheet, colNumber, + reqImageWidthMM, resizeBehaviour); + rowClientAnchorDetail = this.fitImageToRows(sheet, rowNumber, + reqImageHeightMM, resizeBehaviour); + + // Having determined if and how to resize the rows, columns and/or the + // image, create the HSSFClientAnchor object to position the image on + // the worksheet. Note how the two ClientAnchorDetail records are + // interrogated to recover the row/column co-ordinates and any insets. + // The first two parameters are not used currently but could be if the + // need arose to extend the functionality of this code by adding the + // ability to specify that a clear 'border' be placed around the image. + anchor = new HSSFClientAnchor(0, + 0, + colClientAnchorDetail.getInset(), + rowClientAnchorDetail.getInset(), + (short)colClientAnchorDetail.getFromIndex(), + rowClientAnchorDetail.getFromIndex(), + (short)colClientAnchorDetail.getToIndex(), + rowClientAnchorDetail.getToIndex()); + + // For now, set the anchor type to do not move or resize the + // image as the size of the row/column is adjusted. This could easilly + // become another parameter passed to the method. + anchor.setAnchorType(HSSFClientAnchor.DONT_MOVE_AND_RESIZE); + + // Now, add the picture to the workbook. Note that the type is assumed + // to be a JPEG/JPG, this could easily (and should) be parameterised + // however. + int index = sheet.getWorkbook().addPicture(this.imageToBytes(imageFile), + HSSFWorkbook.PICTURE_TYPE_JPEG); + + // Get the drawing patriarch and create the picture. + patriarch = sheet.createDrawingPatriarch(); + patriarch.createPicture(anchor, index); + } + + /** + * Determines whether the sheets columns should be re-sized to accomodate + * the image, adjusts the columns width if necessary and creates then + * returns a ClientAnchorDetail object that facilitates construction of + * an HSSFClientAnchor that will fix the image on the sheet and establish + * it's size. + * + * @param sheet A reference to the sheet that will 'contain' the image. + * @param colNumber A primtive int that contains the index number of a + * column on the sheet. + * @param reqImageWidthMM A primtive double that contains the required + * width of the image in millimetres + * @param resizeBehaviour A primitve int whose value will indicate how the + * width of the column should be adjusted if the + * required width of the image is greater than the + * width of the column. + * @return An instance of the ClientAnchorDetail class that will contain + * the index number of the column containing the cell whose top + * left hand corner also defines the top left hand corner of the + * image, the index number column containing the cell whose top + * left hand corner also defines the bottom right hand corner of + * the image and an inset that determines how far the right hand + * edge of the image can protrude into the next column - expressed + * as a specific number of co-ordinate positions. + */ + private ClientAnchorDetail fitImageToColumns(HSSFSheet sheet, int colNumber, + double reqImageWidthMM, int resizeBehaviour) { + + double colWidthMM = 0.0D; + double colCoordinatesPerMM = 0.0D; + int pictureWidthCoordinates = 0; + ClientAnchorDetail colClientAnchorDetail = null; + + // Get the colum's width in millimetres + colWidthMM = ConvertImageUnits.widthUnits2Millimetres( + (short)sheet.getColumnWidth(colNumber)); + + // Check that the column's width will accomodate the image at the + // required dimension. If the width of the column is LESS than the + // required width of the image, decide how the application should + // respond - resize the column or overlay the image across one or more + // columns. + if(colWidthMM < reqImageWidthMM) { + + // Should the column's width simply be expanded? + if((resizeBehaviour == AddDimensionedImage.EXPAND_COLUMN) || + (resizeBehaviour == AddDimensionedImage.EXPAND_ROW_AND_COLUMN)) { + // Set the width of the column by converting the required image + // width from millimetres into Excel's column width units. + sheet.setColumnWidth(colNumber, + ConvertImageUnits.millimetres2WidthUnits(reqImageWidthMM)); + // To make the image occupy the full width of the column, convert + // the required width of the image into co-ordinates. This value + // will become the inset for the ClientAnchorDetail class that + // is then instantiated. + colWidthMM = reqImageWidthMM; + colCoordinatesPerMM = ConvertImageUnits.TOTAL_COLUMN_COORDINATE_POSITIONS / + colWidthMM; + pictureWidthCoordinates = (int)(reqImageWidthMM * colCoordinatesPerMM); + colClientAnchorDetail = new ClientAnchorDetail(colNumber, + colNumber, pictureWidthCoordinates); + } + // If the user has chosen to overlay both rows and columns or just + // to expand ONLY the size of the rows, then calculate how to lay + // the image out across one or more columns. + else if ((resizeBehaviour == AddDimensionedImage.OVERLAY_ROW_AND_COLUMN) || + (resizeBehaviour == AddDimensionedImage.EXPAND_ROW)) { + colClientAnchorDetail = this.calculateColumnLocation(sheet, + colNumber, reqImageWidthMM); + } + } + // If the column is wider than the image. + else { + // Mow many co-ordinate positions are there per millimetre? + colCoordinatesPerMM = ConvertImageUnits.TOTAL_COLUMN_COORDINATE_POSITIONS / + colWidthMM; + // Given the width of the image, what should be it's co-ordinate? + pictureWidthCoordinates = (int)(reqImageWidthMM * colCoordinatesPerMM); + colClientAnchorDetail = new ClientAnchorDetail(colNumber, + colNumber, pictureWidthCoordinates); + } + return(colClientAnchorDetail); + } + + /** + * Determines whether the sheet's row should be re-sized to accomodate + * the image, adjusts the rows height if necessary and creates then + * returns a ClientAnchorDetail object that facilitates construction of + * an HSSFClientAnchor that will fix the image on the sheet and establish + * it's size. + * + * @param sheet A reference to the sheet that will 'contain' the image. + * @param rowNumber A primtive int that contains the index number of a + * row on the sheet. + * @param reqImageHeightMM A primtive double that contains the required + * height of the image in millimetres + * @param resizeBehaviour A primitve int whose value will indicate how the + * height of the row should be adjusted if the + * required height of the image is greater than the + * height of the row. + * @return An instance of the ClientAnchorDetail class that will contain + * the index number of the row containing the cell whose top + * left hand corner also defines the top left hand corner of the + * image, the index number of the row containing the cell whose + * top left hand corner also defines the bottom right hand + * corner of the image and an inset that determines how far the + * bottom edge of the image can protrude into the next (lower) + * row - expressed as a specific number of co-ordinate positions. + */ + private ClientAnchorDetail fitImageToRows(HSSFSheet sheet, int rowNumber, + double reqImageHeightMM, int resizeBehaviour) { + HSSFRow row = null; + double rowHeightMM = 0.0D; + double rowCoordinatesPerMM = 0.0D; + int pictureHeightCoordinates = 0; + ClientAnchorDetail rowClientAnchorDetail = null; + + // Get the row and it's height + row = sheet.getRow(rowNumber); + if(row == null) { + // Create row if it does not exist. + row = sheet.createRow(rowNumber); + } + + // Get the row's height in millimetres + rowHeightMM = row.getHeightInPoints() / ConvertImageUnits.POINTS_PER_MILLIMETRE; + + // Check that the row's height will accomodate the image at the required + // dimensions. If the height of the row is LESS than the required height + // of the image, decide how the application should respond - resize the + // row or overlay the image across a series of rows. + if(rowHeightMM < reqImageHeightMM) { + if((resizeBehaviour == AddDimensionedImage.EXPAND_ROW) || + (resizeBehaviour == AddDimensionedImage.EXPAND_ROW_AND_COLUMN)) { + row.setHeightInPoints((float)(reqImageHeightMM * + ConvertImageUnits.POINTS_PER_MILLIMETRE)); + rowHeightMM = reqImageHeightMM; + rowCoordinatesPerMM = ConvertImageUnits.TOTAL_ROW_COORDINATE_POSITIONS / + rowHeightMM; + pictureHeightCoordinates = (int)(reqImageHeightMM * rowCoordinatesPerMM); + rowClientAnchorDetail = new ClientAnchorDetail(rowNumber, + rowNumber, pictureHeightCoordinates); + } + // If the user has chosen to overlay both rows and columns or just + // to expand ONLY the size of the columns, then calculate how to lay + // the image out ver one or more rows. + else if((resizeBehaviour == AddDimensionedImage.OVERLAY_ROW_AND_COLUMN) || + (resizeBehaviour == AddDimensionedImage.EXPAND_COLUMN)) { + rowClientAnchorDetail = this.calculateRowLocation(sheet, + rowNumber, reqImageHeightMM); + } + } + // Else, if the image is smaller than the space available + else { + rowCoordinatesPerMM = ConvertImageUnits.TOTAL_ROW_COORDINATE_POSITIONS / + rowHeightMM; + pictureHeightCoordinates = (int)(reqImageHeightMM * rowCoordinatesPerMM); + rowClientAnchorDetail = new ClientAnchorDetail(rowNumber, + rowNumber, pictureHeightCoordinates); + } + return(rowClientAnchorDetail); + } + + /** + * If the image is to overlie more than one column, calculations need to be + * performed to determine how many columns and whether the image will + * overlie just a part of one column in order to be presented at the + * required size. + * + * @param sheet The sheet that will 'contain' the image. + * @param startingColumn A primitive int whose value is the index of the + * column that contains the cell whose top left hand + * corner should be aligned with the top left hand + * corner of the image. + * @param reqImageWidthMM A primitive double whose value will indicate the + * required width of the image in millimetres. + * @return An instance of the ClientAnchorDetail class that will contain + * the index number of the column containing the cell whose top + * left hand corner also defines the top left hand corner of the + * image, the index number column containing the cell whose top + * left hand corner also defines the bottom right hand corner of + * the image and an inset that determines how far the right hand + * edge of the image can protrude into the next column - expressed + * as a specific number of co-ordinate positions. + */ + private ClientAnchorDetail calculateColumnLocation(HSSFSheet sheet, + int startingColumn, + double reqImageWidthMM) { + ClientAnchorDetail anchorDetail = null; + double totalWidthMM = 0.0D; + double colWidthMM = 0.0D; + double overlapMM = 0.0D; + double coordinatePositionsPerMM = 0.0D; + int fromNumber = startingColumn; + int toColumn = startingColumn; + int inset = 0; + + // Calculate how many columns the image will have to + // span in order to be presented at the required size. + while(totalWidthMM < reqImageWidthMM) { + colWidthMM = ConvertImageUnits.widthUnits2Millimetres( + (short)(sheet.getColumnWidth(toColumn))); + // Note use of the cell border width constant. Testing with an image + // declared to fit exactly into one column demonstrated that it's + // width was greater than the width of the column the POI returned. + // Further, this difference was a constant value that I am assuming + // related to the cell's borders. Either way, that difference needs + // to be allowed for in this calculation. + totalWidthMM += (colWidthMM + ConvertImageUnits.CELL_BORDER_WIDTH_MILLIMETRES); + toColumn++; + } + // De-crement by one the last column value. + toColumn--; + // Highly unlikely that this will be true but, if the width of a series + // of columns is exactly equal to the required width of the image, then + // simply build a ClientAnchorDetail object with an inset equal to the + // total number of co-ordinate positions available in a column, a + // from column co-ordinate (top left hand corner) equal to the value + // of the startingColumn parameter and a to column co-ordinate equal + // to the toColumn variable. + // + // Convert both values to ints to perform the test. + if((int)totalWidthMM == (int)reqImageWidthMM) { + // A problem could occur if the image is sized to fit into one or + // more columns. If that occurs, the value in the toColumn variable + // will be in error. To overcome this, there are two options, to + // ibcrement the toColumn variable's value by one or to pass the + // total number of co-ordinate positions to the third paramater + // of the ClientAnchorDetail constructor. For no sepcific reason, + // the latter option is used below. + anchorDetail = new ClientAnchorDetail(startingColumn, + toColumn, ConvertImageUnits.TOTAL_COLUMN_COORDINATE_POSITIONS); + } + // In this case, the image will overlap part of another column and it is + // necessary to calculate just how much - this will become the inset + // for the ClientAnchorDetail object. + else { + // Firstly, claculate how much of the image should overlap into + // the next column. + overlapMM = reqImageWidthMM - (totalWidthMM - colWidthMM); + + // When the required size is very close indded to the column size, + // the calcaulation above can produce a negative value. To prevent + // problems occuring in later caculations, this is simply removed + // be setting the overlapMM value to zero. + if(overlapMM < 0) { + overlapMM = 0.0D; + } + + // Next, from the columns width, calculate how many co-ordinate + // positons there are per millimetre + coordinatePositionsPerMM = ExcelUtil.TOTAL_COLUMN_COORDINATE_POSITIONS / + colWidthMM; + // From this figure, determine how many co-ordinat positions to + // inset the left hand or bottom edge of the image. + inset = (int)(coordinatePositionsPerMM * overlapMM); + + // Now create the ClientAnchorDetail object, setting the from and to + // columns and the inset. + anchorDetail = new ClientAnchorDetail(startingColumn, toColumn, inset); + } + return(anchorDetail); + } + + /** + * If the image is to overlie more than one rows, calculations need to be + * performed to determine how many rows and whether the image will + * overlie just a part of one row in order to be presented at the + * required size. + * + * @param sheet The sheet that will 'contain' the image. + * @param startingRow A primitive int whose value is the index of the row + * that contains the cell whose top left hand corner + * should be aligned with the top left hand corner of + * the image. + * @param reqImageHeightMM A primitive double whose value will indicate the + * required height of the image in millimetres. + * @return An instance of the ClientAnchorDetail class that will contain + * the index number of the row containing the cell whose top + * left hand corner also defines the top left hand corner of the + * image, the index number of the row containing the cell whose top + * left hand corner also defines the bottom right hand corner of + * the image and an inset that determines how far the bottom edge + * can protrude into the next (lower) row - expressed as a specific + * number of co-ordinate positions. + */ + private ClientAnchorDetail calculateRowLocation(HSSFSheet sheet, + int startingRow, double reqImageHeightMM) { + ClientAnchorDetail clientAnchorDetail = null; + HSSFRow row = null; + double rowHeightMM = 0.0D; + double totalRowHeightMM = 0.0D; + double overlapMM = 0.0D; + double rowCoordinatesPerMM = 0.0D; + int toRow = startingRow; + int inset = 0; + + // Step through the rows in the sheet and accumulate a total of their + // heights. + while(totalRowHeightMM < reqImageHeightMM) { + row = sheet.getRow(toRow); + // Note, if the row does not already exist on the sheet then create + // it here. + if(row == null) { + row = sheet.createRow(toRow); + } + // Get the row's height in millimetres and add to the running total. + rowHeightMM = row.getHeightInPoints() / + ConvertImageUnits.POINTS_PER_MILLIMETRE; + totalRowHeightMM += rowHeightMM; + toRow++; + } + // Owing to the way the loop above works, the rowNumber will have been + // incremented one row too far. Undo that here. + toRow--; + // Check to see whether the image should occupy an exact number of + // rows. If so, build the ClientAnchorDetail record to point + // to those rows and with an inset of the total number of co-ordinate + // position in the row. + // + // To overcome problems that can occur with comparing double values for + // equality, cast both to int(s) to truncate the value; VERY crude and + // I do not really like it!! + if((int)totalRowHeightMM == (int)reqImageHeightMM) { + clientAnchorDetail = new ClientAnchorDetail(startingRow, toRow, + ConvertImageUnits.TOTAL_ROW_COORDINATE_POSITIONS); + } + else { + // Calculate how far the image will project into the next row. Note + // that the height of the last row assessed is subtracted from the + // total height of all rows assessed so far. + overlapMM = reqImageHeightMM - (totalRowHeightMM - rowHeightMM); + + // To prevent an exception being thrown when the required width of + // the image is very close indeed to the column size. + if(overlapMM < 0) { + overlapMM = 0.0D; + } + + rowCoordinatesPerMM = ConvertImageUnits.TOTAL_ROW_COORDINATE_POSITIONS / + rowHeightMM; + inset = (int)(overlapMM * rowCoordinatesPerMM); + clientAnchorDetail = new ClientAnchorDetail(startingRow, + toRow, inset); + } + return(clientAnchorDetail); + } + + /** + * Loads - reads in and converts into an array of byte(s) - an image from + * a named file. + * + * Note: this method should be modified so that the type of the image may + * also be passed to it. Currently, it assumes that all images are + * JPG/JPEG(s). + * + * @param imageFilename A String that encapsulates the path to and name + * of the file that contains the image which is to be + * 'loaded'. + * @return An array of type byte that contains the raw data of the named + * image. + * @throws java.io.FileNotFoundException Thrown if it was not possible to + * open the specified file. + * @throws java.io.IOException Thrown if reading the file failed or was + * interrupted. + */ + private byte[] imageToBytes(String imageFilename) + throws FileNotFoundException, IOException { + File imageFile = null; + FileInputStream fis = null; + ByteArrayOutputStream bos = null; + int read = 0; + try { + imageFile = new File(imageFilename); + fis = new FileInputStream(imageFile); + bos = new ByteArrayOutputStream(); + while((read = fis.read()) != -1) { + bos.write(read); + } + return(bos.toByteArray()); + } + finally { + if(fis != null) { + try { + fis.close(); + fis = null; + } + catch(IOException ioEx) { + // Nothing to do here + } + } + } + } + + /** + * The main entry point to the program. It contains code that demonstrates + * one way to use the program. + * + * Note, the code is not restricted to use on new workbooks only. If an + * image is to be inserted into an existing workbook. just open that + * workbook, gat a reference to a sheet and pass that; + * + * AddDimensionedImage addImage = new AddDimensionedImage(); + * + * File file = new File("....... Existing Workbook ......."); + * FileInputStream fis = new FileInputStream(file); + * HSSFWorkbook workbook = new HSSFWorkbook(fis); + * HSSFSheet sheet = workbook.getSheetAt(0); + * addImage.addImageToSheet("C3", sheet, "image.jpg", 30, 20, + * AddDimensionedImage.EXPAND.ROW); + * + * @param args the command line arguments + */ + public static void main(String[] args) { + File file = null; + FileInputStream fis = null; + FileOutputStream fos = null; + HSSFWorkbook workbook = null; + HSSFSheet sheet = null; + try { + workbook = new HSSFWorkbook(); + sheet = workbook.createSheet("Picture Test"); + new AddDimensionedImage().addImageToSheet("B5", sheet, + "image.jpg", 25, 25, + AddDimensionedImage.OVERLAY_ROW_AND_COLUMN); + fos = new FileOutputStream("Workbook.xls"); + workbook.write(fos); + } + catch(FileNotFoundException fnfEx) { + System.out.println("Caught an: " + fnfEx.getClass().getName()); + System.out.println("Message: " + fnfEx.getMessage()); + System.out.println("Stacktrace follows..........."); + fnfEx.printStackTrace(System.out); + } + catch(IOException ioEx) { + System.out.println("Caught an: " + ioEx.getClass().getName()); + System.out.println("Message: " + ioEx.getMessage()); + System.out.println("Stacktrace follows..........."); + ioEx.printStackTrace(System.out); + } + finally { + if(fos != null) { + try { + fos.close(); + fos = null; + } + catch(IOException ioEx) { + // I G N O R E + } + } + } + } + + /** + * The HSSFClientAnchor class accepts eight parameters. In order, these are; + * + * * How far the left hand edge of the image is inset from the left hand + * edge of the cell + * * How far the top edge of the image is inset from the top of the cell + * * How far the right hand edge of the image is inset from the left + * hand edge of the cell + * * How far the bottom edge of the image is inset from the top of the + * cell. + * * Together, parameters five and six determine the column and row + * co-ordinates of the cell whose top left hand corner will be aligned + * with the image's top left hand corner. + * * Together, parameter seven and eight determine the column and row + * co-ordinates of the cell whose top left hand corner will be aligned + * with the images bottom right hand corner. + * + * An instance of the ClientAnchorDetail class provides three of the eight + * parameters, one of the co-ordinates for the images top left hand corner, + * one of the co-ordinates for the images bottom right hand corner and + * either how far the image should be inset from the top or the left hand + * edge of the cell. + * + * @author Mark Beardsley [msb at apache.org] + * @version 1.00 5th August 2009. + */ + public class ClientAnchorDetail { + + public int fromIndex = 0; + public int toIndex = 0; + public int inset = 0; + + /** + * Create a new instance of the ClientAnchorDetail class using the + * following parameters. + * + * @param fromIndex A primitive int that contains one of the + * co-ordinates (row or column index) for the top left + * hand corner of the image. + * @param toIndex A primitive int that contains one of the + * co-ordinates (row or column index) for the bottom + * right hand corner of the image. + * @param inset A primitive int that contains a value which indicates + * how far the image should be inset from the top or the + * left hand edge of a cell. + */ + public ClientAnchorDetail(int fromIndex, int toIndex, int inset) { + this.fromIndex = fromIndex; + this.toIndex = toIndex; + this.inset = inset; + } + + /** + * Get one of the number of the column or row that contains the cell + * whose top left hand corner will be aligned with the top left hand + * corner of the image. + * + * @return The value - row or column index - for one of the co-ordinates + * of the top left hand corner of the image. + */ + public int getFromIndex() { + return(this.fromIndex); + } + + /** + * Get one of the number of the column or row that contains the cell + * whose top left hand corner will be aligned with the bottom righ hand + * corner of the image. + * + * @return The value - row or column index - for one of the co-ordinates + * of the bottom right hand corner of the image. + */ + public int getToIndex() { + return(this.toIndex); + } + + /** + * Get the image's offset from the edge of a cell. + * + * @return How far either the right hand or bottom edge of the image is + * inset from the left hand or top edge of a cell. + */ + public int getInset() { + return(this.inset); + } + } + + /** + * Utility methods used to convert Excel's character based column and row + * size measurements into pixels and/or millimetres. The class also contains + * various constants that are required in other calculations. + * + * @author xio[darjino@hotmail.com] + * @version 1.01 30th July 2009. + * Added by Mark Beardsley [msb at apache.org]. + * Additional constants. + * widthUnits2Millimetres() and millimetres2Units() methods. + */ + public static class ConvertImageUnits { + + // Each cell conatins a fixed number of co-ordinate points; this number + // does not vary with row height or column width or with font. These two + // constants are defined below. + public static final int TOTAL_COLUMN_COORDINATE_POSITIONS = 1023; // MB + public static final int TOTAL_ROW_COORDINATE_POSITIONS = 255; // MB + // The resoultion of an image can be expressed as a specific number + // of pixels per inch. Displays and printers differ but 96 pixels per + // inch is an acceptable standard to beging with. + public static final int PIXELS_PER_INCH = 96; // MB + // Cnstants that defines how many pixels and points there are in a + // millimetre. These values are required for the conversion algorithm. + public static final double PIXELS_PER_MILLIMETRES = 3.78; // MB + public static final double POINTS_PER_MILLIMETRE = 2.83; // MB + // The column width returned by HSSF and the width of a picture when + // positioned to exactly cover one cell are different by almost exactly + // 2mm - give or take rounding errors. This constant allows that + // additional amount to be accounted for when calculating how many + // celles the image ought to overlie. + public static final double CELL_BORDER_WIDTH_MILLIMETRES = 2.0D; // MB + public static final short EXCEL_COLUMN_WIDTH_FACTOR = 256; + public static final int UNIT_OFFSET_LENGTH = 7; + public static final int[] UNIT_OFFSET_MAP = new int[] + { 0, 36, 73, 109, 146, 182, 219 }; + + /** + * pixel units to excel width units(units of 1/256th of a character width) + * @param pxs + * @return + */ + public static short pixel2WidthUnits(int pxs) { + short widthUnits = (short) (EXCEL_COLUMN_WIDTH_FACTOR * + (pxs / UNIT_OFFSET_LENGTH)); + widthUnits += UNIT_OFFSET_MAP[(pxs % UNIT_OFFSET_LENGTH)]; + return widthUnits; + } + + /** + * excel width units(units of 1/256th of a character width) to pixel + * units. + * + * @param widthUnits + * @return + */ + public static int widthUnits2Pixel(short widthUnits) { + int pixels = (widthUnits / EXCEL_COLUMN_WIDTH_FACTOR) + * UNIT_OFFSET_LENGTH; + int offsetWidthUnits = widthUnits % EXCEL_COLUMN_WIDTH_FACTOR; + pixels += Math.round((float) offsetWidthUnits / + ((float) EXCEL_COLUMN_WIDTH_FACTOR / UNIT_OFFSET_LENGTH)); + return pixels; + } + + /** + * Convert Excel's width units into millimetres. + * + * @param widthUnits The width of the column or the height of the + * row in Excel's units. + * @return A primitive double that contains the columns width or rows + * height in millimetres. + */ + public static double widthUnits2Millimetres(short widthUnits) { + return(ConvertImageUnits.widthUnits2Pixel(widthUnits) / + ConvertImageUnits.PIXELS_PER_MILLIMETRES); + } + + /** + * Convert into millimetres Excel's width units.. + * + * @param millimetres A primitive double that contains the columns + * width or rows height in millimetres. + * @return A primitive int that contains the columns width or rows + * height in Excel's units. + */ + public static int millimetres2WidthUnits(double millimetres) { + return(ConvertImageUnits.pixel2WidthUnits((int)(millimetres * + ConvertImageUnits.PIXELS_PER_MILLIMETRES))); + } + } +} \ No newline at end of file -- 2.39.5