Java - 连接到 MYSQL 数据库 try/catch 的代码出错？

Question

我一生都无法弄清楚我的代码中的错误是什么。有人有主意吗？所有错误均来自距底部约 5 行的 catch 语句。

public void connectToDB(){
    try {
    // this will load the MySQL driver, each DB has its own driver
      Class.forName(dbDriver);
      // setup the connection with the DB.
      connect = DriverManager
          .getConnection("jdbc:mysql://localhost/?"
              + "user=root&password=");
    ResultSet resultSet = connect.getMetaData().getCatalogs();

    //iterate each catalog in the ResultSet
    while (resultSet.next()) {
      // Get the database name, which is at position 1
      String databaseName = resultSet.getString(1);
      if (databaseName.equals("Ballers")) {
          preparedStatement = connect.prepareStatement("DROP DATABASE Ballers");
          preparedStatement.execute();
      }
    }
          ScriptRunner runner = new ScriptRunner(connect, false, false);
          try {
            runner.runScript(new BufferedReader(new FileReader(dumpPath)));
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    } catch (ClassNotFoundException | SQLException e) {
        System.out.println("not connecting");
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

}

错误内容如下:

DatabaseHelper.java:64: <identifier> expected
        } catch (ClassNotFoundException | SQLException e) {
                                       ^
DatabaseHelper.java:64: '{' expected
        } catch (ClassNotFoundException | SQLException e) {
                                         ^
DatabaseHelper.java:64: not a statement
        } catch (ClassNotFoundException | SQLException e) {
                                                       ^
DatabaseHelper.java:64: ';' expected
        } catch (ClassNotFoundException | SQLException e) {

需要什么标识符？这不是一个有效的陈述吗？

Answer 1

您必须拥有旧版本的 Java

从 Java 7 开始支持多个异常捕获。您必须单独捕获它们。

转换

} catch (ClassNotFoundException | SQLException e) {
        System.out.println("not connecting");
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

到

} catch (ClassNotFoundException  e) {
        System.out.println("not connecting");
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
} catch ( SQLException e) {
        System.out.println("not connecting");
        // TODO Auto-generated catch block
        e.printStackTrace();
    }