Module java.management

Package javax.management.openmbean

Interface CompositeData

All Known Implementing Classes:

CompositeDataSupport, GcInfo

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

Modifier and Type	Method	Description
boolean	containsKey(String key)	Returns true if and only if this CompositeData instance contains an item whose name is key.
boolean	containsValue(Object value)	Returns true if and only if this CompositeData instance contains an item whose value is value.
boolean	equals(Object obj)	Compares the specified obj parameter with this CompositeData instance for equality.
Object	get(String key)	Returns the value of the item whose name is key.
Object[]	getAll(String[] keys)	Returns an array of the values of the items whose names are specified by keys, in the same order as keys.
CompositeType	getCompositeType()	Returns the composite type of this composite data instance.
int	hashCode()	Returns the hash code value for this CompositeData instance.
String	toString()	Returns a string representation of this CompositeData instance.
Collection<?>	values()	Returns an unmodifiable Collection view of the item values contained in this CompositeData instance.

Method Details

getCompositeType

CompositeType getCompositeType()

Returns the composite type of this composite data instance.

Returns:

the type of this CompositeData.

get

Object get(String key)

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 - if key is a null or empty String.

InvalidKeyException - if key is not an existing item name for this CompositeData instance.

getAll

Object[] getAll(String[] keys)

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 - if an element in keys is a null or empty String.

InvalidKeyException - 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

Collection<?> 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 this CompositeData 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 of Arrays.equals(e1,e2) for arrays of primitive types

This ensures that this equals method works properly for obj parameters which are different implementations of the CompositeData interface, with the restrictions mentioned in the equals method of the java.util.Collection interface.

Overrides:

equals in class Object

Parameters:

obj - the object to be compared for equality with this CompositeData instance.

Returns:

true if the specified object is equal to this CompositeData 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 method Object.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 the deepHashCode method for arrays of object reference types or the appropriate overloading of Arrays.hashCode(e) for arrays of primitive types.

Overrides:

hashCode in class Object

Returns:

the hash code value for this CompositeData instance

See Also:

• Object.equals(java.lang.Object)
• System.identityHashCode(java.lang.Object)

toString

String 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 in class Object

Returns:

a string representation of this CompositeData instance