Java - 如何获取结果集上的列名 [英] Java - How to get Column name on Result Set

问题描述

您好，我想在没有匹配的学生...
时出现错误，它将显示如下
找不到匹配的记录我希望列名仍然相同，但仍然没有想出来...可以有人告诉我，如果这是正确的

Hello I'm trying to make an error when there is no matched student... and it will display like this No matching records found and I want the column name still the same but still not figuring it out... can some one tell me if this is right??

我的函数... ...我在那里添加注释，我把错误...但我不知道如何获取列名

Heres my function for that... and I add comment there where I put the error... but i don't know how to get the columnname

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());
        }
    }

我尝试这样，但仍然给我NULL！ ！
此代码位于 empty = false;

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

推荐答案

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]);
}

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