conn.getMetaData()获取列名重复问题解决

步骤

DriverManager.registerDriver (new oracle.jdbc.driver.OracleDriver());
Connection conn = DriverManager.getConnection(
  "jdbc:oracle:thin:@<server>:1521:<sid>", <username>, <password>);

DatabaseMetaData meta = conn.getMetaData();
ResultSet columns = meta.getColumns(null, null, "EMPLOYEES", null);
int i = 1;
while (columns.next())
{
  System.out.printf("%d: %s (%d)\n", i++, columns.getString("COLUMN_NAME"), 
    columns.getInt("ORDINAL_POSITION"));
}

ResultSet中包含着一套复制所有的列，即每列返回两次。 下面是我得到的输出：

1: ID (1)
2: NAME (2)
3: CITY (3)
4: ID (1)
5: NAME (2)
6: CITY (3)

解决办法，用数组判断列名，防止重复列

//这里是为了防止获取重复的列；
List<String> fieldList = new ArrayList<>();
if(fieldList.size()>0){
    for (String field:fieldList){
        String COLUM = resultSet.getString("COLUMN_NAME");
        String colum = StringUtils.underScoreCase2CamelCase((COLUM.toLowerCase()));
        if(colum.equals(field)){
            return;
        }
    }
}