error: value skill is not a member of object Person private def getSkill() = name + "'s skill is: " + Person.skill
时间: 2024-04-15 13:29:42 浏览: 103
这个错误是因为在Person类中,你尝试访问一个名为skill的静态属性,但是该属性不存在。
在你的代码中,你没有定义一个名为skill的静态属性。如果你想在Person类中定义一个静态属性,你可以使用伴生对象来实现。
以下是一个修正后的示例代码:
```scala
class Person private(val name: String) {
private def getSkill() = name + "'s skill is: " + Person.skill
}
object Person {
private val skill = "Programming"
def create(name: String): Person = {
new Person(name)
}
}
```
在这个修正后的代码中,我们在伴生对象Person中定义了一个名为skill的私有静态属性。现在,你可以在Person类的私有方法getSkill()中访问这个属性,并构建Person类的对象。
请确保在使用Person类之前,先创建它的对象,例如通过调用`Person.create("John")`方法来创建一个名为"John"的Person对象。
相关问题
error: value normal is not a member of breeze.linalg.DenseVector[Double]
This error message is indicating that you are trying to access a member called "normal" on an object of type breeze.linalg.DenseVector[Double], but this member does not exist on that type.
Without more context or code to review, it's difficult to provide a more specific explanation of what might be causing this issue. However, some possible causes could include:
- You may have misspelled the member name, or it may be defined on a different type.
- The object you are trying to access may not actually be a DenseVector[Double], but some other type that does not have a member called "normal".
- There may be a problem with your import statements or dependency setup, causing a missing member or type definition.
To resolve this error, you will need to review your code and ensure that you are accessing the correct member on the correct object. If you are still having trouble, you may need to provide additional context or seek further assistance from a colleague or online community.
error: value toDF is not a member of org.apache.spark.rdd.RDD
这个错误通常是由于没有正确导入 Spark SQL 相关的库而导致的。请确保你的代码中包含以下导入语句:
```scala
import org.apache.spark.sql.SparkSession
import spark.implicits._
```
并且在创建 SparkSession 后,使用 `toDF()` 方法将 RDD 转换为 DataFrame,例如:
```scala
val spark = SparkSession.builder()
.appName("example")
.master("local[*]")
.getOrCreate()
val rdd = spark.sparkContext.parallelize(Seq((1, "John"), (2, "Jane"), (3, "Jim")))
val df = rdd.toDF("id", "name")
df.show()
```
如果仍然遇到问题,请检查 Spark 版本是否与代码兼容,并确保所有依赖项都已正确导入。