Read and Write Excel using Java

To run this u will require jxl.jar

Create.java
------------------------
import java.io.*;
import jxl.*;
import java.util.*;
import jxl.Workbook;
import jxl.write.Number;
import jxl.write.*;

class Create {
public static void main(String[] args) {
try {
String filename = "input.xls";
WorkbookSettings ws = new WorkbookSettings();
ws.setLocale(new Locale("en", "EN"));
WritableWorkbook workbook = Workbook.createWorkbook(new File(
filename), ws);
WritableSheet s = workbook.createSheet("Sheet1", 0);
WritableSheet s1 = workbook.createSheet("Sheet1", 0);
writeDataSheet(s);
writeImageSheet(s1);
workbook.write();
workbook.close();
} catch (IOException e) {
e.printStackTrace();
} catch (WriteException e) {
e.printStackTrace();
}
}

private static void writeDataSheet(WritableSheet s) throws WriteException {

/* Format the Font */
WritableFont wf = new WritableFont(WritableFont.ARIAL, 10,
WritableFont.BOLD);
WritableCellFormat cf = new WritableCellFormat(wf);
cf.setWrap(true);

/* Creates Label and writes date to one cell of sheet */
Label l = new Label(0, 0, "Date", cf);
s.addCell(l);
WritableCellFormat cf1 = new WritableCellFormat(DateFormats.FORMAT9);

DateTime dt = new DateTime(0, 1, new Date(), cf1, DateTime.GMT);

s.addCell(dt);

/* Creates Label and writes float number to one cell of sheet */
l = new Label(2, 0, "Float", cf);
s.addCell(l);
WritableCellFormat cf2 = new WritableCellFormat(NumberFormats.FLOAT);
Number n = new Number(2, 1, 3.1415926535, cf2);
s.addCell(n);

n = new Number(2, 2, -3.1415926535, cf2);
s.addCell(n);

/*
* Creates Label and writes float number upto 3 decimal to one cell of
* sheet
*/
l = new Label(3, 0, "3dps", cf);
s.addCell(l);
NumberFormat dp3 = new NumberFormat("#.###");
WritableCellFormat dp3cell = new WritableCellFormat(dp3);
n = new Number(3, 1, 3.1415926535, dp3cell);
s.addCell(n);

/* Creates Label and adds 2 cells of sheet */
l = new Label(4, 0, "Add 2 cells", cf);
s.addCell(l);
n = new Number(4, 1, 10);
s.addCell(n);
n = new Number(4, 2, 16);
s.addCell(n);
Formula f = new Formula(4, 3, "E1+E2");
s.addCell(f);

/* Creates Label and multipies value of one cell of sheet by 2 */
l = new Label(5, 0, "Multipy by 2", cf);
s.addCell(l);
n = new Number(5, 1, 10);
s.addCell(n);
f = new Formula(5, 2, "F1 * 3");
s.addCell(f);

/* Creates Label and divide value of one cell of sheet by 2.5 */
l = new Label(6, 0, "Divide", cf);
s.addCell(l);
n = new Number(6, 1, 12);
s.addCell(n);
f = new Formula(6, 2, "F1/2.5");
s.addCell(f);
}

private static void writeImageSheet(WritableSheet s) throws WriteException {
/* Creates Label and writes image to one cell of sheet */
Label l = new Label(0, 0, "Image");
s.addCell(l);
WritableImage wi = new WritableImage(0, 3, 5, 7, new File(
"D:\\eclipseWorkspace1\\Excel\\src\\ad_flag.png"));
s.addImage(wi);

/* Creates Label and writes hyperlink to one cell of sheet */
l = new Label(0, 15, "HYPERLINK");
s.addCell(l);
Formula f = new Formula(1, 15,
"HYPERLINK(\"http://www.google.com\", "
+ "\"Anuj\")");
s.addCell(f);

}

}


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Using StringBuffer different methods you can :
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  5. set character at Specific index
  6. delete character at specific index
  7. get subString using specific index
  8. delete characters within String
  9. find String buffer capacity
Java Program to StringBuffer methods example :

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