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Java-如何获取结果集上的列名

问题内容：

您好，当没有匹配的学生时，我正在尝试犯一个错误…它将以这种方式显示， No matching records found并且我希望列名保持不变，但仍无法弄清楚…可以有人告诉我这是否是对？？

这是我的函数…并且在其中添加错误的地方添加了注释…但是我不知道如何获取列名

public void SearchTableStudent() {
        String tempSearchValue = searchStudent.getText().trim();
        boolean empty = true;
        sql = "SELECT student_id as 'Student ID',"
                + "concat(lastname, '  ,  ', firstname, ' ', middlename) as 'Name'"
                + "FROM user "
                + "WHERE CAST(student_id as CHAR) LIKE '%" + tempSearchValue + "%'";
        try {
            pst = conn.prepareStatement(sql);
            rs = pst.executeQuery();
            while(rs.next()) {
                table.setModel(DbUtils.resultSetToTableModel(rs));
                empty = false;
            }
            if(empty) {
                String error = "";
                table.setModel(new javax.swing.table.DefaultTableModel(
                    new Object [][] {
                        {"No matching records found",null}
                    },
                    new String [] {
     /** I WANT TO PUT THE SAME COLUMN NAME ON MY DATABASE SELECTED BUT DON't Know
 WHAT FUNCTION TO DO*/
                    }
                ));
            }
        } catch (Exception e) {
            JOptionPane.showMessageDialog(null, e.getMessage());
        }
    }

我这样尝试，但仍然给了我NULL！该代码在以下empty = false;

for(int i=0; i<table.getColumnCount(); i++) {
    test[i] = table.getColumnName(i);
}

问题答案：

ResultSetMetaData metaData = resultSet.getMetaData();
int count = metaData.getColumnCount(); //number of column
String columnName[] = new String[count];

for (int i = 1; i <= count; i++)
{
   columnName[i-1] = metaData.getColumnLabel(i);
   System.out.println(columnName[i-1]);
}