javax.management.openmbean

Class TabularDataSupport

public class TabularDataSupport extends Object implements TabularData, Serializable, Cloneable, Map<Object,Object>

Provides an implementation of the TabularData interface using a java.util.HashMap.

Since: 1.5

Constructor Summary
TabularDataSupport(TabularType type)
Constructs a new empty TabularDataSupport with the specified type.
TabularDataSupport(TabularType type, int cap, float lf)
Constructs a new empty TabularDataSupport with the specified type and the supplied initial capacity and load factor being used for the underlying java.util.HashMap.
Method Summary
Object[]calculateIndex(CompositeData val)
Calculates the index the specified CompositeData value would have, if it was to be added to this TabularData instance.
voidclear()
Removes all CompositeData values from the table.
booleancontainsKey(Object key)
Returns true iff this instance of the TabularData class contains a CompositeData value at the specified index.
booleancontainsKey(Object[] key)
Returns true iff this instance of the TabularData class contains a CompositeData value at the specified index.
booleancontainsValue(Object val)
Returns true iff this instance of the TabularData class contains the specified CompositeData value.
booleancontainsValue(CompositeData val)
Returns true iff this instance of the TabularData class contains the specified CompositeData value.
Set<Entry<Object,Object>>entrySet()

Returns a set view of the mappings in this Map.

booleanequals(Object obj)
Compares the specified object with this object for equality.
Objectget(Object key)
Retrieves the value for the specified key by simply calling get((Object[]) key).
CompositeDataget(Object[] key)
Retrieves the CompositeData value for the specified key, or null if no such mapping exists.
TabularTypegetTabularType()
Returns the tabular type which corresponds to this instance of TabularData.
inthashCode()
Returns the hash code of the composite data type.
booleanisEmpty()
Returns true if this TabularData instance contains no CompositeData values.
Set<Object>keySet()
Returns a set view of the keys in this Map.
voidput(CompositeData val)
Adds the specified CompositeData value to the table.
Objectput(Object key, Object val)
Adds the specified CompositeData value to the table, ignoring the supplied key, by simply calling put((CompositeData) val).
voidputAll(CompositeData[] vals)
Adds each of the specified CompositeData values to the table.
voidputAll(Map<?,?> m)
Converts each value from the specified map to a member of an array of CompositeData values and adds them using (CompositeData[]), if possible.
Objectremove(Object key)
Removes the value for the specified key by simply calling remove((Object[]) key).
CompositeDataremove(Object[] key)
Removes the CompositeData value located at the specified index.
intsize()
Returns the number of CompositeData values or rows in the table.
StringtoString()
Returns a textual representation of this instance.
Collection<Object>values()
Returns a collection (or bag) view of the values in this Map.

Constructor Detail

TabularDataSupport

public TabularDataSupport(TabularType type)
Constructs a new empty TabularDataSupport with the specified type. The type may not be null. This constructor simply calls the other, with the default initial capacity of 101 and default load factor of 0.75.

Parameters: type the tabular type of this tabular data instance.

Throws: IllegalArgumentException if type is null.

TabularDataSupport

public TabularDataSupport(TabularType type, int cap, float lf)
Constructs a new empty TabularDataSupport with the specified type and the supplied initial capacity and load factor being used for the underlying java.util.HashMap. The type may not be null and the initial capacity and load factor must be positive.

Parameters: type the tabular type of this tabular data instance. cap the initial capacity of the underlying map. lf the load factor of the underlying map.

Throws: IllegalArgumentException if type is null, or cap or lf are negative.

Method Detail

calculateIndex

public Object[] calculateIndex(CompositeData val)
Calculates the index the specified CompositeData value would have, if it was to be added to this TabularData instance. This method includes a check that the type of the given value is the same as the row type of this instance, but not a check for existing instances of the given value. The value must also not be null. Possible indices are selected by the getIndexNames method of this instance's tabular type. The returned indices are the values of the fields in the supplied CompositeData instance that match the names given in the TabularType.

Parameters: val the CompositeData value whose index should be calculated.

Returns: the index the value would take on, if it were to be added.

Throws: NullPointerException if the value is null. InvalidOpenTypeException if the value does not match the row type of this instance.

clear

public void clear()
Removes all CompositeData values from the table.

containsKey

public boolean containsKey(Object key)
Returns true iff this instance of the TabularData class contains a CompositeData value at the specified index. The method returns false if the given key can not be cast to an java.lang.Object array; otherwise it returns the result of (java.lang.Object[]).

Parameters: key the key to test for.

Returns: true if the key maps to a CompositeData value.

containsKey

public boolean containsKey(Object[] key)
Returns true iff this instance of the TabularData class contains a CompositeData value at the specified index. In any other circumstance, including if the given key is null or of the incorrect type, according to the TabularType of this instance, this method returns false.

Parameters: key the key to test for.

Returns: true if the key maps to a CompositeData value.

containsValue

public boolean containsValue(Object val)
Returns true iff this instance of the TabularData class contains the specified CompositeData value. If the given value is not an instance of CompositeData, this method simply returns false.

Parameters: val the value to test for.

Returns: true if the value exists.

containsValue

public boolean containsValue(CompositeData val)
Returns true iff this instance of the TabularData class contains the specified CompositeData value. In any other circumstance, including if the given value is null or of the incorrect type, according to the TabularType of this instance, this method returns false.

Parameters: val the value to test for.

Returns: true if the value exists.

entrySet

public Set<Entry<Object,Object>> entrySet()

Returns a set view of the mappings in this Map. Each element in the set is a Map.Entry. The set is backed by the map, so that changes in one show up in the other. Modifications made while an iterator is in progress cause undefined behavior. If the set supports removal, these methods remove the underlying mapping from the map: Iterator.remove, Set.remove, removeAll, retainAll, and clear. Element addition, via add or addAll, is not supported via this set.

Note: using the java.util.Map.Entry#setValue(Object) will cause corruption of the index to row mappings.

Returns: the set view of all mapping entries

See Also: java.util.Map.Entry

equals

public boolean equals(Object obj)
Compares the specified object with this object for equality. The object is judged equivalent if it is non-null, and also an instance of TabularData with the same row type, and CompositeData values. The two compared instances may be equivalent even if they represent different implementations of TabularData.

Parameters: obj the object to compare for equality.

Returns: true if obj is equal to this.

get

public Object get(Object key)
Retrieves the value for the specified key by simply calling get((Object[]) key).

Parameters: key the key whose value should be returned.

Returns: the matching CompositeData value, or null if one does not exist.

Throws: NullPointerException if the key is null. ClassCastException if the key is not an instance of Object[]. InvalidKeyException if the key does not match the TabularType of this instance.

get

public CompositeData get(Object[] key)
Retrieves the CompositeData value for the specified key, or null if no such mapping exists.

Parameters: key the key whose value should be returned.

Returns: the matching CompositeData value, or null if one does not exist.

Throws: NullPointerException if the key is null. InvalidKeyException if the key does not match the TabularType of this instance.

getTabularType

public TabularType getTabularType()
Returns the tabular type which corresponds to this instance of TabularData.

Returns: the tabular type for this instance.

hashCode

public int hashCode()
Returns the hash code of the composite data type. This is computed as the sum of the hash codes of each value, together with the hash code of the tabular type. These are the same elements of the type that are compared as part of the TabularDataSupport method, thus ensuring that the hashcode is compatible with the equality test.

Returns: the hash code of this instance.

isEmpty

public boolean isEmpty()
Returns true if this TabularData instance contains no CompositeData values.

Returns: true if the instance is devoid of rows.

keySet

public Set<Object> keySet()
Returns a set view of the keys in this Map. The set is backed by the map, so that changes in one show up in the other. Modifications made while an iterator is in progress cause undefined behavior. If the set supports removal, these methods remove the underlying mapping from the map: Iterator.remove, Set.remove, removeAll, retainAll, and clear. Element addition, via add or addAll, is not supported via this set.

Returns: the set view of all keys

put

public void put(CompositeData val)
Adds the specified CompositeData value to the table. The value must be non-null, of the same type as the row type of this instance, and must not have the same index as an existing value. The index is calculated using the index names of the TabularType for this instance.

Parameters: val the CompositeData value to add.

Throws: NullPointerException if val is null. InvalidOpenTypeException if the type of the given value does not match the row type. KeyAlreadyExistsException if the value has the same calculated index as an existing value.

put

public Object put(Object key, Object val)
Adds the specified CompositeData value to the table, ignoring the supplied key, by simply calling put((CompositeData) val).

Parameters: key ignored. val the CompositeData value to add.

Returns: the CompositeData value.

Throws: NullPointerException if val is null. InvalidOpenTypeException if the type of the given value does not match the row type. KeyAlreadyExistsException if the value has the same calculated index as an existing value.

putAll

public void putAll(CompositeData[] vals)
Adds each of the specified CompositeData values to the table. Each element of the array must meet the conditions given for the put method. In addition, the index of each value in the array must be distinct from the index of the other values in the array, as well as from the existing values in the table. The operation should be atomic; if one value can not be added, then none of the values should be. If the array is null or empty, the method simply returns.

Parameters: vals the CompositeData values to add.

Throws: NullPointerException if a value from the array is null. InvalidOpenTypeException if the type of a given value does not match the row type. KeyAlreadyExistsException if a value has the same calculated index as an existing value or of one of the other specified values.

putAll

public void putAll(Map<?,?> m)
Converts each value from the specified map to a member of an array of CompositeData values and adds them using (CompositeData[]), if possible. As in put, the keys are simply ignored. This method is useful for adding the CompositeData values from a different TabularData instance, which uses the same TabularType but a different selection of index names, to this one. If the map is null or empty, the method simply returns.

Parameters: m the map to add. Only the values are used and must all be instances of CompositeData.

Throws: NullPointerException if a value from the map is null. ClassCastException if a value from the map is not an instance of CompositeData. InvalidOpenTypeException if the type of the given value does not match the row type. KeyAlreadyExistsException if the value has the same calculated index as an existing value or of one of the other specified values.

remove

public Object remove(Object key)
Removes the value for the specified key by simply calling remove((Object[]) key).

Parameters: key the key whose value should be removed.

Returns: the removed value, or null if there is no value for the given key.

Throws: NullPointerException if the key is null. ClassCastException if the key is not an instance of Object[]. InvalidOpenTypeException if the key does not match the TabularType of this instance.

remove

public CompositeData remove(Object[] key)
Removes the CompositeData value located at the specified index. null is returned if the value does not exist. Otherwise, the removed value is returned.

Parameters: key the key of the value to remove.

Returns: the removed value, or null if there is no value for the given key.

Throws: NullPointerException if the key is null. InvalidOpenTypeException if the key does not match the TabularType of this instance.

size

public int size()
Returns the number of CompositeData values or rows in the table.

Returns: the number of rows in the table.

toString

public String toString()
Returns a textual representation of this instance. This is constructed using the class name (javax.management.openmbean.TabularDataSupport) and the result of calling toString() on the tabular type and underlying hash map instance.

Returns: a java.lang.String representation of the object.

values

public Collection<Object> values()
Returns a collection (or bag) view of the values in this Map. The collection is backed by the map, so that changes in one show up in the other. Modifications made while an iterator is in progress cause undefined behavior. If the collection supports removal, these methods remove the underlying mapping from the map: Iterator.remove, Collection.remove, removeAll, retainAll, and clear. Element addition, via add or addAll, is not supported via this collection.

Returns: the collection view of all values