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Class structure.Table 

java.lang.Object
    |
    +----structure.Table
public class Table
extends Object
implements OrderedDictionary
An implementation of an ordered dictionary. Key-value pairs are kept in the structure in order. To accomplish this, the keys of the table must be comparable.

See Also:
Comparable

Constructor Index

o Table()
Construct a new, empty table.

Method Index

o clear()
Remove all the elements of the table.
o contains(Object)
Returns true if the value is associated with some key in the table.
o containsKey(Object)
Determine if the key is in the table.
o elements()
Construct an iterator over the values of the table.
o get(Object)
Retrieve the value associated with the key provided.
o isEmpty()
Determine if the table is empty.
o keys()
Construct an iterator over the keys of the table.
o put(Object, Object)
Enter a key-value pair into the table.
o remove(Object)
Remove a key-value pair, based on key.
o size()
Determine the number of key-value pairs within the table.
o toString()
Construct a string representing value of table.

Constructors

o Table 
public Table()
Construct a new, empty table.

Postcondition:
constructs a new table

Methods

o get 
public Object get(Object key)
Retrieve the value associated with the key provided. Be aware, the value may be null.

Precondition:
key is a non-null object
Postcondition:
returns value associated with key, or null

Parameters:
key - The key of the key-value pair sought.
Returns:
The value associated with the key.
o put 
public Object put(Object key,
                  Object value)
Enter a key-value pair into the table. if the key is already in the table, the old value is returned, and the old key-value pair is replaced. Otherwise null is returned. The user is cautioned that a null value returned may indicate there was no prior key-value pair, or --- if null values are inserted --- that the key was previously associated with a null value.

Precondition:
key is non-null object
Postcondition:
key-value pair is added to table

Parameters:
key - The unique key in the table.
value - The (possibly null) value associated with key.
Returns:
The prior value, or null if no prior value found.
o isEmpty 
public boolean isEmpty()
Determine if the table is empty.

Postcondition:
returns true iff table is empty

Returns:
True iff the table has no elements.
o clear 
public void clear()
Remove all the elements of the table.

Postcondition:
removes all elements from the table

o keys 
public Iterator keys()
Construct an iterator over the keys of the table. The order of the keys returned is in ascending order. It will be consistent with that of the iterator from elements, provided the table is not modified.

Postcondition:
returns an iterator for traversing keys of table

Returns:
An iterator over the keys of the table.
o elements 
public Iterator elements()
Construct an iterator over the values of the table. The order of the values returned is determined by order of keys. It will be consistent with that of the iterator returned from keys, provided the table is not modified.

Postcondition:
returns an iterator for traversing values in table

Returns:
An iterator over the values of the table.
o containsKey 
public boolean containsKey(Object key)
Determine if the key is in the table. The key should not be null.

Precondition:
key is non-null object
Postcondition:
returns true iff key indexes a value in table

Parameters:
key - A non-null key sought in the table.
Returns:
True iff the key is used in association with some value.
o contains 
public boolean contains(Object value)
Returns true if the value is associated with some key in the table. This is often difficult to implement efficiently.

Precondition:
value is non-null object
Postcondition:
returns true iff value in table

Parameters:
value - The value sought (possibly null).
Returns:
True, if the value is associated with some key in table.
o remove 
public Object remove(Object key)
Remove a key-value pair, based on key. The value is returned.

Precondition:
key is non-null object
Postcondition:
removes value indexed in table

Parameters:
key - The key of the key-value pair to be removed.
Returns:
The value associated with key, no longer in table.
o size 
public int size()
Determine the number of key-value pairs within the table.

Postcondition:
returns number of key-value pairs in table

Returns:
The number of key-value pairs in the table.
o toString 
public String toString()
Construct a string representing value of table.

Postcondition:
returns string representation

Returns:
String representing table.
Overrides:
toString in class Object
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