javax.management.openmbean

Class TabularDataSupport

Implemented Interfaces:
Cloneable, Map<K,V>, Serializable, TabularData

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

Provides an implementation of the TabularData interface using a HashMap.
Since:
1.5
See Also:
Serialized Form

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 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.
void
clear()
Removes all CompositeData values from the table.
Object
clone()
Returns a shallow clone of the information, as obtained by the Object implementation of Object.clone().
boolean
containsKey(Object key)
Returns true iff this instance of the TabularData class contains a CompositeData value at the specified index.
boolean
containsKey(Object[] key)
Returns true iff this instance of the TabularData class contains a CompositeData value at the specified index.
boolean
containsValue(Object val)
Returns true iff this instance of the TabularData class contains the specified CompositeData value.
boolean
containsValue(CompositeData val)
Returns true iff this instance of the TabularData class contains the specified CompositeData value.
Set>
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 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 TabularData.
int
hashCode()
Returns the hash code of the composite data type.
boolean
isEmpty()
Returns true if this TabularData instance contains no CompositeData values.
Set
keySet()
Returns a set view of the keys in this Map.
Object
put(Object key, Object val)
Adds the specified CompositeData value to the table, ignoring the supplied key, by simply calling put((CompositeData) val).
void
put(CompositeData val)
Adds the specified CompositeData value to the table.
void
putAll(Map m)
Converts each value from the specified map to a member of an array of CompositeData values and adds them using put(CompositeData[]), if possible.
void
putAll(CompositeData[] vals)
Adds each of the specified CompositeData values to the table.
Object
remove(Object key)
Removes the value for the specified key by simply calling remove((Object[]) key).
CompositeData
remove(Object[] key)
Removes the CompositeData value located at the specified index.
int
size()
Returns the number of CompositeData values or rows in the table.
String
toString()
Returns a textual representation of this instance.
Collection
values()
Returns a collection (or bag) view of the values in this Map.

Methods inherited from class java.lang.Object

clone, equals, extends Object> getClass, finalize, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

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 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 Details

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 TabularType.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.
Specified by:
calculateIndex in interface TabularData
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.
Specified by:
clear in interface TabularData
clear in interface Map<K,V>

clone

public Object clone()
Returns a shallow clone of the information, as obtained by the Object implementation of Object.clone(). The map is also cloned, but it still references the same objects.
Overrides:
clone in interface Object
Returns:
a shallow clone of this TabularDataSupport.

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 Object array; otherwise it returns the result of containsKey(Object[]).
Specified by:
containsKey in interface Map<K,V>
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.
Specified by:
containsKey in interface TabularData
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.
Specified by:
containsValue in interface Map<K,V>
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.
Specified by:
containsValue in interface TabularData
Parameters:
val - the value to test for.
Returns:
true if the value exists.

entrySet

public Set> 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. @return the set view of all mapping entries @see 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.
Specified by:
equals in interface TabularData
equals in interface Map<K,V>
Overrides:
equals in interface Object
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).
Specified by:
get in interface Map<K,V>
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.
Specified by:
get in interface TabularData
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.
Specified by:
getTabularType in interface 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 equals(Object) method, thus ensuring that the hashcode is compatible with the equality test.
Specified by:
hashCode in interface TabularData
hashCode in interface Map<K,V>
Overrides:
hashCode in interface Object
Returns:
the hash code of this instance.

isEmpty

public boolean isEmpty()
Returns true if this TabularData instance contains no CompositeData values.
Specified by:
isEmpty in interface TabularData
isEmpty in interface Map<K,V>
Returns:
true if the instance is devoid of rows.

keySet

public Set 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.
Specified by:
keySet in interface TabularData
keySet in interface Map<K,V>
Returns:
the set view of all keys

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.

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.
Specified by:
put in interface TabularData
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.

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 put(CompositeData[]), if possible. As in put(Object,Object), 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.

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(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.
Specified by:
putAll in interface TabularData
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.

remove

public Object remove(Object key)
Removes the value for the specified key by simply calling remove((Object[]) key).
Specified by:
remove in interface Map<K,V>
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.
Specified by:
remove in interface TabularData
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.
Specified by:
size in interface TabularData
size in interface Map<K,V>
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.
Specified by:
toString in interface TabularData
Overrides:
toString in interface Object
Returns:
a String representation of the object.

values

public Collection 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.
Specified by:
values in interface TabularData
values in interface Map<K,V>
Returns:
the collection view of all values

TabularDataSupport.java -- Tables of composite data structures. Copyright (C) 2006, 2007 Free Software Foundation, Inc. This file is part of GNU Classpath. GNU Classpath is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GNU Classpath is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Classpath; see the file COPYING. If not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. Linking this library statically or dynamically with other modules is making a combined work based on this library. Thus, the terms and conditions of the GNU General Public License cover the whole combination. As a special exception, the copyright holders of this library give you permission to link this library with independent modules to produce an executable, regardless of the license terms of these independent modules, and to copy and distribute the resulting executable under terms of your choice, provided that you also meet, for each linked independent module, the terms and conditions of the license of that module. An independent module is a module which is not derived from or based on this library. If you modify this library, you may extend this exception to your version of the library, but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version.