如何动态填充二维数组

Question

我想用这种模式显示结果集值：

Object rowData[][] = { { url , tags , text }, { url , tags , text } };

我的代码是：

while (res.next()) {
    String url = res.getString(1);
    String tags = res.getString(2);
    String text = res.getString(3);
}
Object rowData[][] = { { "Row1-Column1", "Row1-Column2", "Row1-Column3" },
                { "Row2-Column1", "Row2-Column2", "Row2-Column3" } };

Object columnNames[] = { "URL", "Tag Information", "Text" };
JTable table = new JTable(rowData, columnNames);`

Answer 1

使用列表存储数据的每个文件，然后将列表转换为数组：

List<Object[]> data = new ArrayList<Object[]>();
while (res.next()) {
    data.add(new Object[]{res.getString(1), res.getString(2),res.getString(3)});
}

Object[][] rowData = data.toArray(new Object[0][0]);
JTable table = new JTable(rowData, columnNames);

Answer 2

看这个简单的例子：

public static void main(String[] args) {

    int rows    = 3; //res.getCount() ?
    int columns = 3;

    Object[][] rawData = new Object[rows][columns];

    for(int row = 0; row < rows; row++){
        rawData[row][0] = row + " - url";
        rawData[row][1] = row + " - tags";
        rawData[row][2] = row + " - text";
    }

    System.out.println(Arrays.toString(rawData[0])); // print first row
}

循环内的字符串连接是一个非常糟糕的主意，但这仅是示例

Answer 3

下面是conde片段，可用于实现您想要的内容。

int rowcount = 0;
if (res.last()) {
    rowcount = res.getRow();
    res.beforeFirst();
}
Object rowData[][] = new Object[rowcount][];
int count = 0;
while (res.next()) {
    rowData[count] = new Object[]    {res.getString(1),res.getString(1),res.getString(3)};  
    count++;
}
Object columnNames[] = { "URL", "Tag Information", "Text" };
JTable table = new JTable(rowData, columnNames);