Package org.apache.spark.sql.types

Class Metadata

Object
org.apache.spark.sql.types.Metadata
All Implemented Interfaces:
Serializable
public class Metadata extends Object implements Serializable
Metadata is a wrapper over Map[String, Any] that limits the value type to simple ones: Boolean, Long, Double, String, Metadata, Array[Boolean], Array[Long], Array[Double], Array[String], and Array[Metadata]. JSON is used for serialization.

The default constructor is private. User should use either MetadataBuilder or Metadata.fromJson() to create Metadata instances.

param: map an immutable map that stores the data

Since:
1.3.0
See Also:

  • Method Details

    • empty

      public static Metadata empty()
      Returns an empty Metadata.

    • fromJson

      public static Metadata fromJson(String json)
      Creates a Metadata instance from JSON.

    • contains

      public boolean contains(String key)
      Tests whether this Metadata contains a binding for a key.

    • isEmpty

      public boolean isEmpty()
      Tests whether this Metadata is empty.

      Returns:
      (undocumented)
      Since:
      4.0.0

    • getLong

      public long getLong(String key)
      Gets a Long.

    • getDouble

      public double getDouble(String key)
      Gets a Double.

    • getBoolean

      public boolean getBoolean(String key)
      Gets a Boolean.

    • getString

      public String getString(String key)
      Gets a String.

    • getMetadata

      public Metadata getMetadata(String key)
      Gets a Metadata.

    • getLongArray

      public long[] getLongArray(String key)
      Gets a Long array.

    • getDoubleArray

      public double[] getDoubleArray(String key)
      Gets a Double array.

    • getBooleanArray

      public boolean[] getBooleanArray(String key)
      Gets a Boolean array.

    • getStringArray

      public String[] getStringArray(String key)
      Gets a String array.

    • getMetadataArray

      public Metadata[] getMetadataArray(String key)
      Gets a Metadata array.

    • json

      public String json()
      Converts to its JSON representation.

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • equals

      public boolean equals(Object obj)
      Overrides:
      equals in class Object

    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class Object