问题
I have an existing excel spreadsheet, which I am accesssing and reading values from, I am using Apache POI HSSF.
It is initialised like this:
HSSFSheet sheet;
FileInputStream fis = new FileInputStream(this.file);
POIFSFileSystem fs = new POIFSFileSystem(fis);
HSSFWorkbook wb = new HSSFWorkbook(fs);
this.sheet = wb.getSheet(exsheet);
I am iterating over all the cells that exist in the sheet, which makes a cell object:
HSSFCell cell = (HSSFCell) cells.next();
Please can someone familiar with the framework explain how to create an (HSSFColor) object to represent the backround color of each cell in the sheet.
Many thanks
EDIT, UPDATE
To be clear what I want to know is: how do I create/get an HSSFColor object for the background color of an existing cell?
cell.getCellStyle().getFillBackgroundColor();
This code only returns a short number, not an HSSFColor object. Thanks for the answers so far.
回答1:
There are static color classes provided by the HSSFCell class, listed here:
http://poi.apache.org/apidocs/org/apache/poi/hssf/util/HSSFColor.html
If you want to create your own custom colors, you will need to create and modify a custom palette. Apache provides a very clear guide to this as well:
http://poi.apache.org/spreadsheet/quick-guide.html#CustomColors
回答2:
To get the color : The short value returned by the getFillBackgroundColor is the Excel index of the color. You can get the color corresponding to the index in the HSSFColor HashTable, using the last code RMorrisey indicated.
To set a color : You create a custom palette, and change the color at a given index. Then, you apply the color to the style.
//creating a custom palette for the workbook
HSSFPalette palette = wb.getCustomPalette();
//replacing the standard red with freebsd.org red
palette.setColorAtIndex(HSSFColor.RED.index,
(byte) 153, //RGB red (0-255)
(byte) 0, //RGB green
(byte) 0 //RGB blue
);
// or creating a new Color
HSSFColor myColor = palette.addColor((byte) 153, (byte) 0, (byte) 0);
HSSFCellStyle style = wb.createCellStyle();
style.setFillForegroundColor(myColor);
Regards
Guillaume
回答3:
The backgroundcolor information of XSSFCellStyle can get from the method:
XSSFCellStyle.getFillForegroundXSSFColor().getCTColor()
You can print it out and you will see it's structure.
回答4:
You would do something like:
HSSFCell myCell = ...;
HSSFCellStyle myStyle = workbook.createCellStyle();
myStyle.setFillBackgroundColor(HSSFColor.BLUE);
myCell.setCellStyle(myStyle);
I believe there is a limited number of styles for a given workbook; you will want to reuse the same style object where possible.
[Edit: Sorry, that would be to set the color on a cell. To get the color, use like:
myCell.getCellStyle().getFillBackgroundColor();
]
[Edit 2: Looking at the custom color information craig posted, maybe you can try:
HSSFColor.getIndexHash().get(myCell.getCellStyle().getFillBackgroundColor())
]
回答5:
To get the background color of the specific cell in HEX, use this:
cell.getCellStyle().getFillForegroundColorColor().getARGBHex()
Notice the word Color is used twice
回答6:
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Iterator;
import org.apache.poi.hssf.usermodel.HSSFPalette;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.util.HSSFColor;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.CellStyle;
import org.apache.poi.ss.usermodel.Row;
/**
* @author mohdasif_2688@rocketmail.com
*
*/
public class ExcelPractice {
/**
* Must Read :
*
* Code to get the background color from an excel sheet in RGB Format and display on the console
* Save the content of the xls file into another OUTPUT.xls file.
* Using a sample sheet with only first row filled with background color.
* Code uses HSSF which means i am only using xls format.
* Using poi-3.5-FINAL.jar
* Solution with the output provided
* Observation : Some Custom color's are not recognized as they may not be defined
* in the excel color palette thus the code returns the almost similar color code.
*/
public static void main(String[] args) {
try {
FileInputStream fileInputStream=new FileInputStream(new File("D:\\Excel_File.xls"));
HSSFWorkbook workbook=new HSSFWorkbook(fileInputStream);
HSSFSheet sheet=workbook.getSheetAt(0);
Iterator<Row> rowIterator= sheet.iterator();
while (rowIterator.hasNext()) {
Row row=rowIterator.next();
Iterator<Cell> cellIterator=row.cellIterator();
while (cellIterator.hasNext()) {
Cell cell = (Cell) cellIterator.next();
switch (cell.getCellType()) {
case Cell.CELL_TYPE_BOOLEAN:
System.out.println(cell.getBooleanCellValue()+"\t\t");
System.out.println(cell.getCellStyle().getFillForegroundColor());
break;
case Cell.CELL_TYPE_NUMERIC:
System.out.println(cell.getNumericCellValue()+"\t\t");
System.out.println(cell.getCellStyle().getFillForegroundColor());
break;
case Cell.CELL_TYPE_STRING:
System.out.println(cell.getStringCellValue()+"\t\t");
//System.out.println(HSSFColor.getIndexHash().get(cell.getCellStyle().getFillBackgroundColor()));
int num=cell.getColumnIndex();
Cell cell1 = row.getCell(num);
CellStyle cellStyle = cell1.getCellStyle();
getColorPattern(cellStyle.getFillForegroundColor());
break;
default:
break;
}
}
System.out.println();
fileInputStream.close();
FileOutputStream fileOutputStream=new FileOutputStream(new File("D:\\OUTPUT.xls"));
workbook.write(fileOutputStream);
fileInputStream.close();
}
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.toString();
}
catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
//Method to identify the color pattern
private static short[] getColorPattern(short colorIdx){
short[] triplet = null;
HSSFWorkbook workbook=new HSSFWorkbook();
HSSFPalette palette = workbook.getCustomPalette();
HSSFColor color = palette.getColor(colorIdx);
triplet = color.getTriplet();
System.out.println("color : " + triplet[0] +"," + triplet[1] + "," + triplet[2]);
return triplet;
}
}
/** Output of the above code as executed in my system
S.NO.
color : 255,255,0
VTU Number
color : 0,128,0
First Name
color : 51,204,204
Middle Name
color : 255,0,0
Last Name
color : 102,102,153
Branch
color : 255,102,0
E-mail id
color : 0,255,0
Mobile Number
color : 255,255,255
*/
回答7:
The following is for XSSF and is in Scala but it does show exactly how to get the colour from the object model. I wanted to instantiate a java.awt.Color object from the actual rgb values (which is useful partly because my debugger displays for me the actual colour of the object when I stop at breakpoints, and partly because this is for export to systems that have nothing to do with Excel). I'm ignoring the colour's alpha value and my Scala may be a bit naive. I'd suggest that if this doesn't work for you, you should set a break-point and examine the result of closely related method calls such as getFillBackgroundColorColor()
val rgb: Array[Byte] = cell.getCellStyle.getFillForegroundColorColor.getRgb
def toInt(b: Byte): Int = {
if (b<0) 256+b else b
}
val rgbInts = rgb.map(toInt)
val color = new Color(rgbInts(0),rgbInts(1),rgbInts(2))
回答8:
For XSSF reading xlsx file (tried the HSSF as well) ,after struggle for a while, i just found getFillBackgroundXSSFColor() method actually returned the "Pattern Color" in the Fill tab of "Format Cells" in Excel, not the so-called "Background" color in that tab. I am not sure if this expected.
See my below screenshot. The returned RGB is actually FF0000 ,i.e. RED.
XSSFColor backgroundColor = cell.getCellStyle().
getFillBackgroundXSSFColor();
System.out.println("backgroundColor is "+backgroundColor.getARGBHex());
Output: FFFF0000 //the first FF should be ignored.
So right now, I do not have a way for this case and just request user to fill the "Pattern Color" as well.
来源：https://stackoverflow.com/questions/1499739/how-do-i-get-the-java-apache-poi-hssf-background-color-for-a-given-cell