Cassandra：無論數據類型如何，如何獲取列數據的字符串值

Question

我正在嘗試從com.datastax.driver.core.ResultSet獲取結果並進行打印：

ResultSet results = getSession().execute("Select * from test.table"); //getsession returns a session
int numcols = results.getColumnDefinitions().size();
for ( Row row : results ) {
    for (int colIndex = 0; colIndex < numcols; colIndex++) {
           System.out.println("data: " + row.getString(colIndex));
     }
}

如果數據類型不是String，則row.getString(colIndex)引發異常。 無論字符串是什么數據類型，我如何都能得到它？

Answer 1

此代碼將打印每列的類型和值

ResultSet results = getSession().execute("Select * from test.table");    
int numcols = results.getColumnDefinitions().size();
for ( Row row : results ) {
   for (int colIndex = 0; colIndex < numcols; colIndex++) {
         System.out.println("Type : "+row.getColumnDefinitions().getType(colIndex));
         Class c = row.getColumnDefinitions().getType(colIndex).asJavaClass();
         if(c == Integer.class) {
              System.out.println("Data :" + row.getInt(colIndex));
         }
         //similar for other type
   }
}