Package com.ericsson.otp.erlang

Class OtpErlangMap

java.lang.Object
com.ericsson.otp.erlang.OtpErlangObject
com.ericsson.otp.erlang.OtpErlangMap
All Implemented Interfaces:
Serializable, Cloneable
public class OtpErlangMap extends OtpErlangObject
Provides a Java representation of Erlang maps. Maps are created from one or more arbitrary Erlang terms.

The arity of the map is the number of elements it contains. The keys and values can be retrieved as arrays and the value for a key can be queried.

See Also:

  • Constructor Details

    • OtpErlangMap

      public OtpErlangMap()
      Create an empty map.

    • OtpErlangMap

      public OtpErlangMap(OtpErlangObject[] keys, OtpErlangObject[] values)
      Create a map from an array of keys and an array of values.
      Parameters:
      keys - the array of terms to create the map keys from.
      values - the array of terms to create the map values from.
      Throws:
      IllegalArgumentException - if any array is empty (null) or contains null elements.

    • OtpErlangMap

      public OtpErlangMap(OtpErlangObject[] keys, int kstart, int kcount, OtpErlangObject[] values, int vstart, int vcount)
      Create a map from an array of terms.
      Parameters:
      keys - the array of terms to create the map from.
      kstart - the offset of the first key to insert.
      kcount - the number of keys to insert.
      values - the array of values to create the map from.
      vstart - the offset of the first value to insert.
      vcount - the number of values to insert.
      Throws:
      IllegalArgumentException - if any array is empty (null) or contains null elements.
      IllegalArgumentException - if kcount and vcount differ.

    • OtpErlangMap

      public OtpErlangMap(OtpInputStream buf) throws OtpErlangDecodeException
      Create a map from a stream containing a map encoded in Erlang external format.
      Parameters:
      buf - the stream containing the encoded map.
      Throws:
      OtpErlangDecodeException - if the buffer does not contain a valid external representation of an Erlang map.

  • Method Details

    • arity

      public int arity()
      Get the arity of the map.
      Returns:
      the number of elements contained in the map.

    • put

      public OtpErlangObject put(OtpErlangObject key, OtpErlangObject value)
      Put value corresponding to key into the map. For detailed behavior description see Map.put(Object, Object).
      Parameters:
      key - key to associate value with
      value - value to associate with key
      Returns:
      previous value associated with key or null

    • remove

      public OtpErlangObject remove(OtpErlangObject key)
      removes mapping for the key if present.
      Parameters:
      key - key for which mapping is to be remove
      Returns:
      value associated with key or null

    • get

      public OtpErlangObject get(OtpErlangObject key)
      Get the specified value from the map.
      Parameters:
      key - the key of the requested value.
      Returns:
      the requested value, of null if key is not a valid key.

    • keys

      public OtpErlangObject[] keys()
      Get all the keys from the map as an array.
      Returns:
      an array containing all of the map's keys.

    • values

      public OtpErlangObject[] values()
      Get all the values from the map as an array.
      Returns:
      an array containing all of the map's values.

    • entrySet

      public Set<Map.Entry<OtpErlangObject,OtpErlangObject>> entrySet()
      make Set view of the map key-value pairs
      Returns:
      a set containing key-value pairs

    • toString

      public String toString()
      Get the string representation of the map.
      Specified by:
      toString in class OtpErlangObject
      Returns:
      the string representation of the map.

    • encode

      public void encode(OtpOutputStream buf)
      Convert this map to the equivalent Erlang external representation.
      Specified by:
      encode in class OtpErlangObject
      Parameters:
      buf - an output stream to which the encoded map should be written.

    • equals

      public boolean equals(Object o)
      Determine if two maps are equal. Maps are equal if they have the same arity and all of the elements are equal.
      Specified by:
      equals in class OtpErlangObject
      Parameters:
      o - the map to compare to.
      Returns:
      true if the maps have the same arity and all the elements are equal.

    • match

      public <T> boolean match(OtpErlangObject term, T binds)
      Description copied from class: OtpErlangObject
      Perform match operation against given term.
      Overrides:
      match in class OtpErlangObject
      Parameters:
      term - the object to match
      binds - variable bindings
      Returns:
      true if match succeeded

    • bind

      public <T> OtpErlangObject bind(T binds) throws OtpErlangException
      Description copied from class: OtpErlangObject
      Make new Erlang term replacing variables with the respective values from bindings argument(s).
      Overrides:
      bind in class OtpErlangObject
      Parameters:
      binds - variable bindings
      Returns:
      new term
      Throws:
      OtpErlangException

    • doHashCode

      protected int doHashCode()
      Overrides:
      doHashCode in class OtpErlangObject

    • clone

      public Object clone()
      Overrides:
      clone in class OtpErlangObject