javax.management.openmbean

Class TabularDataSupport

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

Provides an implementation of the {@link TabularData} interface using a {@link java.util.HashMap}.

Since: 1.5

Constructor Summary
	TabularDataSupport(TabularType type) Constructs a new empty {@link TabularDataSupport} with the specified type.
	TabularDataSupport(TabularType type, int cap, float lf) Constructs a new empty {@link TabularDataSupport} with the specified type and the supplied initial capacity and load factor being used for the underlying {@link java.util.HashMap}.

Method Summary
Object[]	calculateIndex(CompositeData val) Calculates the index the specified {@link CompositeData} value would have, if it was to be added to this {@link TabularData} instance.
void	clear() Removes all {@link CompositeData} values from the table.
Object	clone() Returns a shallow clone of the information, as obtained by the {@link Object} implementation of {@link Object#clone()}.
boolean	containsKey(Object key) Returns true iff this instance of the {@link TabularData} class contains a {@link CompositeData} value at the specified index.
boolean	containsKey(Object[] key) Returns true iff this instance of the {@link TabularData} class contains a {@link CompositeData} value at the specified index.
boolean	containsValue(Object val) Returns true iff this instance of the {@link TabularData} class contains the specified {@link CompositeData} value.
boolean	containsValue(CompositeData val) Returns true iff this instance of the {@link TabularData} class contains the specified {@link CompositeData} value.
Set<Entry<Object,Object>>	entrySet() Returns a set view of the mappings in this Map.
boolean	equals(Object obj) Compares the specified object with this object for equality.
Object	get(Object key) Retrieves the value for the specified key by simply calling `get((Object[]) key)`.
CompositeData	get(Object[] key) Retrieves the {@link CompositeData} value for the specified key, or `null` if no such mapping exists.
TabularType	getTabularType() Returns the tabular type which corresponds to this instance of {@link TabularData}.
int	hashCode() Returns the hash code of the composite data type.
boolean	isEmpty() Returns true if this {@link TabularData} instance contains no {@link CompositeData} values.
Set<Object>	keySet() Returns a set view of the keys in this Map.
void	put(CompositeData val) Adds the specified {@link CompositeData} value to the table.
Object	put(Object key, Object val) Adds the specified {@link CompositeData} value to the table, ignoring the supplied key, by simply calling `put((CompositeData) val)`.
void	putAll(CompositeData[] vals) Adds each of the specified {@link CompositeData} values to the table.
void	putAll(Map<?,?> m) Converts each value from the specified map to a member of an array of {@link CompositeData} values and adds them using {@link #put(CompositeData[])}, if possible.
Object	remove(Object key) Removes the value for the specified key by simply calling `remove((Object[]) key)`.
CompositeData	remove(Object[] key) Removes the {@link CompositeData} value located at the specified index.
int	size() Returns the number of {@link CompositeData} values or rows in the table.
String	toString() 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 {@link 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 {@link TabularDataSupport} with the specified type and the supplied initial capacity and load factor being used for the underlying {@link 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 {@link CompositeData} value would have, if it was to be added to this {@link 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 {@link TabularType#getIndexNames()} method of this instance's tabular type. The returned indices are the values of the fields in the supplied {@link CompositeData} instance that match the names given in the {@link TabularType}.

Parameters: val the {@link 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 {@link CompositeData} values from the table.

clone

public Object clone()

Returns a shallow clone of the information, as obtained by the {@link Object} implementation of {@link Object#clone()}. The map is also cloned, but it still references the same objects.

Returns: a shallow clone of this {@link TabularDataSupport}.

containsKey

public boolean containsKey(Object key)

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

Parameters: key the key to test for.

Returns: true if the key maps to a {@link CompositeData} value.

containsKey

public boolean containsKey(Object[] key)

Returns true iff this instance of the {@link TabularData} class contains a {@link 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 {@link TabularType} of this instance, this method returns false.

Parameters: key the key to test for.

Returns: true if the key maps to a {@link CompositeData} value.

containsValue

public boolean containsValue(Object val)

Returns true iff this instance of the {@link TabularData} class contains the specified {@link CompositeData} value. If the given value is not an instance of {@link 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 {@link TabularData} class contains the specified {@link CompositeData} value. In any other circumstance, including if the given value is null or of the incorrect type, according to the {@link 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 {@link java.util.Map.Entry#setValue(Object) will cause corruption of the index to row mappings.

Returns: the set view of all mapping entries

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 {@link TabularData} with the same row type, and {@link CompositeData} values. The two compared instances may be equivalent even if they represent different implementations of {@link 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 {@link 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 {@link TabularType} of this instance.

get

public CompositeData get(Object[] key)

Retrieves the {@link 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 {@link CompositeData} value, or null if one does not exist.

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

getTabularType

public TabularType getTabularType()

Returns the tabular type which corresponds to this instance of {@link 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 {@link #equals(java.lang.Object)} 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 {@link TabularData} instance contains no {@link 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 {@link 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 {@link TabularType} for this instance.

Parameters: val the {@link 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 {@link CompositeData} value to the table, ignoring the supplied key, by simply calling put((CompositeData) val).

Parameters: key ignored. val the {@link CompositeData} value to add.

Returns: the {@link CompositeData} value.

putAll

public void putAll(CompositeData[] vals)

Adds each of the specified {@link CompositeData} values to the table. Each element of the array must meet the conditions given for the {@link #put(CompositeData)} 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 {@link 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 {@link CompositeData} values and adds them using {@link #put(CompositeData[])}, if possible. As in {@link #put(Object,Object)}, the keys are simply ignored. This method is useful for adding the {@link CompositeData} values from a different {@link TabularData} instance, which uses the same {@link 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 {@link CompositeData}.

Throws: NullPointerException if a value from the map is null. ClassCastException if a value from the map is not an instance of {@link 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 {@link TabularType} of this instance.

remove

public CompositeData remove(Object[] key)

Removes the {@link 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 {@link TabularType} of this instance.

size

public int size()

Returns the number of {@link 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 {@link 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