import org.apache.poi.xwpf.usermodel.*;

                Iterator <XWPFTable> it = doc.getTablesIterator();
                while (it.hasNext()) {
                    XWPFTable table = (XWPFTable) it.next();
                    int rcount = table.getNumberOfRows();
                    for (int i = 0; i < rcount; i++) {
                        XWPFTableRow row = table.getRow(i);
                        List<XWPFTableCell> cells = row.getTableCells();
                        for (XWPFTableCell cell : cells) {
                            String cellTextString = cell.getText();
                            for (Entry<String, String> e : map.entrySet()) {
                                if (cellTextString.contains(e.getKey()))
                                    cellTextString = cellTextString
                                            .replace(e.getKey(),
                                                    e.getValue());
                            }                            
                            cell.removeParagraph(0);                            
                            cell.setText(cellTextString);
                        }
                    }
                }

cell.removeParagraph(0);  
cell.setText(cellTextString);