CompositeData (Java SE 15 & JDK 15) (original) (raw)

All Known Implementing Classes:

[CompositeDataSupport](CompositeDataSupport.html "class in javax.management.openmbean"), [GcInfo](../../../../jdk.management/com/sun/management/GcInfo.html "class in com.sun.management")

public interface CompositeData

The CompositeData interface specifies the behavior of a specific type of complex open data objects which represent composite data structures.

Since:

1.5

• Method Summary

• Method Details

  • getCompositeType

  Returns the composite type of this composite data instance.
  Returns:
  the type of this CompositeData.

  • get

  Returns the value of the item whose name is key.
  Parameters:
  key - the name of the item.
  Returns:
  the value associated with this key.
  Throws:
  [IllegalArgumentException](../../../../java.base/java/lang/IllegalArgumentException.html "class in java.lang") - if key is a null or empty String.
  [InvalidKeyException](InvalidKeyException.html "class in javax.management.openmbean") - if key is not an existing item name for this CompositeData instance.

  • getAll

  Returns an array of the values of the items whose names are specified by keys, in the same order as keys.
  Parameters:
  keys - the names of the items.
  Returns:
  the values corresponding to the keys.
  Throws:
  [IllegalArgumentException](../../../../java.base/java/lang/IllegalArgumentException.html "class in java.lang") - if an element in keys is a null or empty String.
  [InvalidKeyException](InvalidKeyException.html "class in javax.management.openmbean") - if an element in keys is not an existing item name for this CompositeData instance.

  • containsKey

  boolean containsKey​(String key)
  Returns true if and only if this CompositeData instance contains an item whose name is key. If key is a null or empty String, this method simply returns false.
  Parameters:
  key - the key to be tested.
  Returns:
  true if this CompositeData contains the key.

  • containsValue

  boolean containsValue​(Object value)
  Returns true if and only if this CompositeData instance contains an item whose value is value.
  Parameters:
  value - the value to be tested.
  Returns:
  true if this CompositeData contains the value.

  • values

  Returns an unmodifiable Collection view of the item values contained in this CompositeData instance. The returned collection's iterator will return the values in the ascending lexicographic order of the corresponding item names.
  Returns:
  the values.

  • equals

  boolean equals​(Object obj)
  Compares the specified obj parameter with thisCompositeData instance for equality.
  Returns true if and only if all of the following statements are true:
  * obj is non null,
  * obj also implements the CompositeData interface,
  * their composite types are equal
  * their contents, i.e. (name, value) pairs are equal. If a value contained in the content is an array, the value comparison is done as if by calling the deepEquals method for arrays of object reference types or the appropriate overloading ofArrays.equals(e1,e2) for arrays of primitive types
  This ensures that this equals method works properly forobj parameters which are different implementations of theCompositeData interface, with the restrictions mentioned in theequals method of the java.util.Collection interface.
  Overrides:
  [equals](../../../../java.base/java/lang/Object.html#equals%28java.lang.Object%29) in class [Object](../../../../java.base/java/lang/Object.html "class in java.lang")
  Parameters:
  obj - the object to be compared for equality with thisCompositeData instance.
  Returns:
  true if the specified object is equal to thisCompositeData instance.
  See Also:
  Object.hashCode(), HashMap

  • hashCode

  int hashCode()
  Returns the hash code value for this CompositeData instance.
  The hash code of a CompositeData instance is the sum of the hash codes of all elements of information used in equals comparisons (ie: its composite type and all the item values).
  This ensures that t1.equals(t2) implies that t1.hashCode()==t2.hashCode() for any two CompositeData instances t1 and t2, as required by the general contract of the methodObject.hashCode().
  Each item value's hash code is added to the returned hash code. If an item value is an array, its hash code is obtained as if by calling thedeepHashCode method for arrays of object reference types or the appropriate overloading of Arrays.hashCode(e) for arrays of primitive types.
  Overrides:
  [hashCode](../../../../java.base/java/lang/Object.html#hashCode%28%29) in class [Object](../../../../java.base/java/lang/Object.html "class in java.lang")
  Returns:
  the hash code value for this CompositeData instance
  See Also:
  Object.equals(java.lang.Object), System.identityHashCode(java.lang.Object)

  • toString

  Returns a string representation of this CompositeData instance.
  The string representation consists of the name of the implementing class, the string representation of the composite type of this instance, and the string representation of the contents (ie list the itemName=itemValue mappings).
  Overrides:
  [toString](../../../../java.base/java/lang/Object.html#toString%28%29) in class [Object](../../../../java.base/java/lang/Object.html "class in java.lang")
  Returns:
  a string representation of this CompositeData instance