headersTabItem.setControl(container);
final TableViewer tableViewer = new TableViewer(container, SWT.BORDER
| SWT.FULL_SELECTION);
TableViewerColumn column = new TableViewerColumn(tableViewer, SWT.NONE);
column.setLabelProvider(new ReassignmentUsersLabelProvider());
column.setEditingSupport(new ReassignmentUsersEditing(tableViewer));
column.getColumn().setText("Users");
column.getColumn().setWidth(100);
column.getColumn().setMoveable(true);
TableViewerColumn column2 = new TableViewerColumn(tableViewer, SWT.NONE);
column2.setLabelProvider(new ReassignmentGroupsLabelProvider());
column2.setEditingSupport(new ReassignmentGroupsEditing(tableViewer));
column2.getColumn().setText("Groups");
column2.getColumn().setWidth(100);
column2.getColumn().setMoveable(true);
TableViewerColumn column3 = new TableViewerColumn(tableViewer, SWT.NONE);
column3.setLabelProvider(new ReassignmentExpiresAtLabelProvider());
column3.setEditingSupport(new ReassignmentExpiresAtEditing(tableViewer));
column3.getColumn().setText("Expires At");
column3.getColumn().setWidth(100);
column3.getColumn().setMoveable(true);
TableViewerColumn column4 = new TableViewerColumn(tableViewer, SWT.NONE);
column4.setLabelProvider(new ReassignmentTypeLabelProvider());
column4.setEditingSupport(new ReassignmentTypeEditing(tableViewer));
column4.getColumn().setText("Type");
column4.getColumn().setWidth(100);
column4.getColumn().setMoveable(true);
final Table table = tableViewer.getTable();
final GridData gd_table = new GridData(SWT.FILL, SWT.CENTER, true, false, 2, 1);
gd_table.heightHint = 128;
table.setLayoutData(gd_table);