jxl WritableCellFormat 实例不能太多

读写文件，一个输出流《——》一个文件，对应一个读写操作。
jxl写文件，一个输出流flush后，WritableCellFormat 需要重新初始化。
即使，这个变量是类静态变量，这个object仍存在，但写excel时格式化信息失效。
所以如下提供format没任何意义，要提供每次请求都实例话的方法
public static WritableCell getNormalAlignLeftContentCell(int column, int row,
            String content) {
        return new jxl.write.Label(column, row, content,
                CellFormat.initNormalAlignLeftCellFormat());
    }

jxl对format实例数量有限制，百个左右。
所以要处理好，文件操作和重新实例化方法调用。
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cell 格式实例 < 100, 否则回抛
Warning:  Maximum number of format records exceeded.  Using default format.

使用静态变量

public abstract class CellFormat {

    private CellFormat() { }
    //format 格式
    private static WritableCellFormat defaultFormat1;
    private static WritableCellFormat defaultFormat2;
    private static WritableCellFormat dateFormat1;
    private static WritableCellFormat dateFormat2;
    private static WritableCellFormat numFormat1;
    private static WritableCellFormat numFormat2;
    static {
        try {
            defaultFormat1 = new WritableCellFormat();
            defaultFormat1.setAlignment(jxl.format.Alignment.CENTRE);
            defaultFormat1.setVerticalAlignment(jxl.format.VerticalAlignment.CENTRE);
          
            defaultFormat2 = new WritableCellFormat();
            defaultFormat2.setAlignment(jxl.format.Alignment.LEFT);
            defaultFormat2.setVerticalAlignment(jxl.format.VerticalAlignment.CENTRE);
          
            dateFormat1 = new WritableCellFormat(new jxl.write.DateFormat("yyyy-MM-dd hh:mm:ss"));
            dateFormat1.setAlignment(jxl.format.Alignment.CENTRE);
            dateFormat1.setVerticalAlignment(jxl.format.VerticalAlignment.CENTRE);
          
            dateFormat2 =  new WritableCellFormat(new jxl.write.DateFormat("yyyy年MM月dd日"));
            dateFormat2.setAlignment(jxl.format.Alignment.CENTRE);
            dateFormat2.setVerticalAlignment(jxl.format.VerticalAlignment.CENTRE);
          
            numFormat1 = new WritableCellFormat(new NumberFormat("￥0.00"));
            numFormat1.setAlignment(jxl.format.Alignment.CENTRE);
            numFormat1.setVerticalAlignment(jxl.format.VerticalAlignment.CENTRE);
          
            numFormat2 =  new WritableCellFormat(new NumberFormat("0.00"));
            numFormat2.setAlignment(jxl.format.Alignment.CENTRE);
            numFormat2.setVerticalAlignment(jxl.format.VerticalAlignment.CENTRE);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
  
    public static WritableCellFormat initNormalCellFormat() {
        return defaultFormat1;
    }

  
    public static WritableCellFormat initNormalAlignLeftCellFormat() {
        return defaultFormat2;
    }

  
    public static WritableCellFormat initDateCellFormat() {
        return dateFormat1;
    }

  
    public static WritableCellFormat initBirthdayCellFormat() {
        return dateFormat2;
    }
  
  
    public static WritableCellFormat initAmountCellFormat() {
        return numFormat1;
    }

  
    public static WritableCellFormat initFloatMiscCellFormat() {
        return numFormat2;
    }

}

评论

1 楼 sky00800 2009-08-18  

[color=white][/color]热热热