R
- the type of the table row keysC
- the type of the table column keysV
- the type of the mapped values@GwtCompatible public interface Table<R,C,V>
A collection that associates an ordered pair of keys, called a row key and a column key, with a single value. A table may be sparse, with only a small fraction of row key / column key pairs possessing a corresponding value.
The mappings corresponding to a given row key may be viewed as a Map
whose keys are the columns. The reverse is also available, associating a column with a row key / value map. Note that, in some implementations, data access by column key may have fewer supported operations or worse performance than data access by row key.
The methods returning collections or maps always return views of the underlying table. Updating the table can change the contents of those collections, and updating the collections will change the table.
All methods that modify the table are optional, and the views returned by the table may or may not be modifiable. When modification isn’t supported, those methods will throw an UnsupportedOperationException
.
See the Guava User Guide article on Table
.
Modifier and Type | Interface and Description |
---|---|
static interface |
Table.Cell<R,C,V>
Row key / column key / value triplet corresponding to a mapping in a table.
|
Modifier and Type | Method and Description |
---|---|
Set<Table.Cell<R,C,V>> |
cellSet()
Returns a set of all row key / column key / value triplets.
|
void |
clear()
Removes all mappings from the table.
|
Map<R,V> |
column(C columnKey)
Returns a view of all mappings that have the given column key.
|
Set<C> |
columnKeySet()
Returns a set of column keys that have one or more values in the table.
|
Map<C,Map<R,V>> |
columnMap()
Returns a view that associates each column key with the corresponding map from row keys to values.
|
boolean |
contains(Object rowKey,
Object columnKey)
Returns
true if the table contains a mapping with the specified row and column keys. |
boolean |
containsColumn(Object columnKey)
Returns
true if the table contains a mapping with the specified column. |
boolean |
containsRow(Object rowKey)
Returns
true if the table contains a mapping with the specified row key. |
boolean |
containsValue(Object value)
Returns
true if the table contains a mapping with the specified value. |
boolean |
equals(Object obj)
Compares the specified object with this table for equality.
|
V |
get(Object rowKey,
Object columnKey)
Returns the value corresponding to the given row and column keys, or
null if no such mapping exists. |
int |
hashCode()
Returns the hash code for this table.
|
boolean |
isEmpty()
Returns
true if the table contains no mappings. |
V |
put(R rowKey,
C columnKey,
V value)
Associates the specified value with the specified keys.
|
void |
putAll(Table<? extends R,? extends C,? extends V> table)
Copies all mappings from the specified table to this table.
|
V |
remove(Object rowKey,
Object columnKey)
Removes the mapping, if any, associated with the given keys.
|
Map<C,V> |
row(R rowKey)
Returns a view of all mappings that have the given row key.
|
Set<R> |
rowKeySet()
Returns a set of row keys that have one or more values in the table.
|
Map<R,Map<C,V>> |
rowMap()
Returns a view that associates each row key with the corresponding map from column keys to values.
|
int |
size()
Returns the number of row key / column key / value mappings in the table.
|
Collection<V> |
values()
Returns a collection of all values, which may contain duplicates.
|
boolean contains(@Nullable Object rowKey, @Nullable Object columnKey)
Returns true
if the table contains a mapping with the specified row and column keys.
rowKey
- key of row to search forcolumnKey
- key of column to search forboolean containsRow(@Nullable Object rowKey)
Returns true
if the table contains a mapping with the specified row key.
rowKey
- key of row to search forboolean containsColumn(@Nullable Object columnKey)
Returns true
if the table contains a mapping with the specified column.
columnKey
- key of column to search forboolean containsValue(@Nullable Object value)
Returns true
if the table contains a mapping with the specified value.
value
- value to search forV get(@Nullable Object rowKey, @Nullable Object columnKey)
Returns the value corresponding to the given row and column keys, or null
if no such mapping exists.
rowKey
- key of row to search forcolumnKey
- key of column to search forboolean isEmpty()
Returns true
if the table contains no mappings.
int size()
Returns the number of row key / column key / value mappings in the table.
boolean equals(@Nullable Object obj)
Compares the specified object with this table for equality. Two tables are equal when their cell views, as returned by cellSet()
, are equal.
int hashCode()
Returns the hash code for this table. The hash code of a table is defined as the hash code of its cell view, as returned by cellSet()
.
void clear()
Removes all mappings from the table.
@Nullable V put(R rowKey, C columnKey, V value)
Associates the specified value with the specified keys. If the table already contained a mapping for those keys, the old value is replaced with the specified value.
rowKey
- row key that the value should be associated withcolumnKey
- column key that the value should be associated withvalue
- value to be associated with the specified keysnull
if no mapping existed for the keysvoid putAll(Table<? extends R,? extends C,? extends V> table)
Copies all mappings from the specified table to this table. The effect is equivalent to calling put(R, C, V)
with each row key / column key / value mapping in table
.
table
- the table to add to this table@Nullable V remove(@Nullable Object rowKey, @Nullable Object columnKey)
Removes the mapping, if any, associated with the given keys.
rowKey
- row key of mapping to be removedcolumnKey
- column key of mapping to be removednull
if no such value existedMap<C,V> row(R rowKey)
Returns a view of all mappings that have the given row key. For each row key / column key / value mapping in the table with that row key, the returned map associates the column key with the value. If no mappings in the table have the provided row key, an empty map is returned.
Changes to the returned map will update the underlying table, and vice versa.
rowKey
- key of row to search for in the tableMap<R,V> column(C columnKey)
Returns a view of all mappings that have the given column key. For each row key / column key / value mapping in the table with that column key, the returned map associates the row key with the value. If no mappings in the table have the provided column key, an empty map is returned.
Changes to the returned map will update the underlying table, and vice versa.
columnKey
- key of column to search for in the tableSet<Table.Cell<R,C,V>> cellSet()
Returns a set of all row key / column key / value triplets. Changes to the returned set will update the underlying table, and vice versa. The cell set does not support the add
or addAll
methods.
Set<R> rowKeySet()
Returns a set of row keys that have one or more values in the table. Changes to the set will update the underlying table, and vice versa.
Set<C> columnKeySet()
Returns a set of column keys that have one or more values in the table. Changes to the set will update the underlying table, and vice versa.
Collection<V> values()
Returns a collection of all values, which may contain duplicates. Changes to the returned collection will update the underlying table, and vice versa.
Map<R,Map<C,V>> rowMap()
Returns a view that associates each row key with the corresponding map from column keys to values. Changes to the returned map will update this table. The returned map does not support put()
or putAll()
, or setValue()
on its entries.
In contrast, the maps returned by rowMap().get()
have the same behavior as those returned by row(R)
. Those maps may support setValue()
, put()
, and putAll()
.
Map<C,Map<R,V>> columnMap()
Returns a view that associates each column key with the corresponding map from row keys to values. Changes to the returned map will update this table. The returned map does not support put()
or putAll()
, or setValue()
on its entries.
In contrast, the maps returned by columnMap().get()
have the same behavior as those returned by column(C)
. Those maps may support setValue()
, put()
, and putAll()
.