DBObjectTable

java.lang.Object
- arlut.csd.ganymede.server.DBObjectTable

All Implemented Interfaces:

java.lang.Iterable<DBObject>
```
public final class DBObjectTable
extends java.lang.Object
implements java.lang.Iterable<DBObject>
```
A customized variant of the java.util.Hashtable class that is tuned for use in managing DBObjects in a Ganymede DBObjectBase.

Author:

Jonathan Abbey, jonabbey@arlut.utexas.edu, ARL:UT

Field Summary

Fields
Modifier and Type	Field and Description
`private int`	`count` The total number of entries in the hash table.
`private float`	`loadFactor` The load factor for the hashtable.
`private int`	`modGen` Tracking value to detect concurrent modification for the enumerations and iterators we generate.
`private DBObject[]`	`table` The hash table data.
`private int`	`threshold` Rehashes the table when count exceeds this threshold.

Constructor Summary

Constructors
Constructor and Description
`DBObjectTable()` Constructs a new, empty DBObjectTable with a default capacity and load factor.
`DBObjectTable(int initialCapacity)` Constructs a new, empty DBObjectTable with the specified initial capacity and default load factor.
`DBObjectTable(int initialCapacity, float loadFactor)` Constructs a new, empty DBObjectTable with the specified initial capacity and the specified load factor.

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`clear()` Clears this DBObjectTable.
`boolean`	`contains(DBObject value)` Tests if the DBObject value is contained in this DBObjectTable.
`boolean`	`containsKey(int key)` Tests if a DBObject with the specified object id is in this DBObjectTable.
`java.util.Enumeration`	`elements()` Returns an enumeration of the objects in this DBObjectTable.
`DBObject`	`get(int key)` Returns the DBObject with the specified key from this DBObjectTable, or null if no object with that id is in this table.
`int`	`getModGen()` Returns a modification generation value for the enumerator and iterator that are generated from this DBObjectTable.
`DBObject`	`getNoSync(int key)` Returns the DBObject with the specified key from this DBObjectTable, or null if no object with that id is in this table.
`boolean`	`isEmpty()` Tests if this DBObjectTable contains no objects.
`java.util.Iterator<DBObject>`	`iterator()` Returns an Iterator of the objects in this DBObjectTable.
`void`	`put(DBObject value)` Inserts a DBObject into this DBObjectTable
`void`	`putNoSync(DBObject value)` Inserts a DBObject into this DBObjectTable.
`void`	`putNoSyncNoRemove(DBObject value)` Inserts a DBObject into this DBObjectTable.
`protected void`	`rehash()` Rehashes the contents of the DBObjectTable into a DBObjectTable with a larger capacity.
`void`	`remove(int key)` Removes the DBObject with the given id from this DBObjectTable.
`void`	`removeNoSync(int key)` Removes the DBObject with the given id from this DBObjectTable.
`void`	`replaceNoSync(DBObject replaceObject)` Replaces a DBObject in the table in-place without disturbing any Iterators running.
`int`	`size()` Returns the number of objects in this DBObjectTable.
`java.util.Collection<DBObject>`	`values()` Returns a non-editable Collection view of this DBObjectTable.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - table
```
private transient DBObject[] table
```
    The hash table data.
  - count
```
private transient int count
```
    The total number of entries in the hash table.
  - threshold
```
private int threshold
```
    Rehashes the table when count exceeds this threshold.
  - loadFactor
```
private float loadFactor
```
    The load factor for the hashtable.
  - modGen
```
private transient int modGen
```
    Tracking value to detect concurrent modification for the enumerations and iterators we generate.
- Constructor Detail
  - DBObjectTable
```
public DBObjectTable(int initialCapacity,
             float loadFactor)
```
    Constructs a new, empty DBObjectTable with the specified initial capacity and the specified load factor.
    
    Parameters:
    initialCapacity - the initial capacity of the hashtable.
    loadFactor - a number between 0.0 and 1.0.
    
    Throws:
    
    java.lang.IllegalArgumentException - if the initial capacity is less than or equal to zero, or if the load factor is less than or equal to zero.
  - DBObjectTable
```
public DBObjectTable(int initialCapacity)
```
    Constructs a new, empty DBObjectTable with the specified initial capacity and default load factor.
    
    Parameters:
    initialCapacity - the initial capacity of the hashtable.
  - DBObjectTable
```
public DBObjectTable()
```
    Constructs a new, empty DBObjectTable with a default capacity and load factor.
- Method Detail
  - getModGen
```
public int getModGen()
```
    Returns a modification generation value for the enumerator and iterator that are generated from this DBObjectTable.
  - size
```
public int size()
```
    Returns the number of objects in this DBObjectTable.
    
    Returns:
    the number of objects in this DBObjectTable.
  - isEmpty
```
public boolean isEmpty()
```
    Tests if this DBObjectTable contains no objects.
    
    Returns:
    true if this DBObjectTable contains no values; false otherwise.
  - iterator
```
public java.util.Iterator<DBObject> iterator()
```
    Returns an Iterator of the objects in this DBObjectTable.
    
    Use the Iterator methods on the returned object to fetch the elements sequentially.
    
    This method allows DBObjectTable to support the Java 5 foreach loop construct.
    
    Specified by:
    
    iterator in interface java.lang.Iterable<DBObject>
    
    Returns:
    an Iterator of the objects in this DBObjectTable.
    See Also:
    Iterator
  - elements
```
public java.util.Enumeration elements()
```
    Returns an enumeration of the objects in this DBObjectTable. Use the Enumeration methods on the returned object to fetch the elements sequentially.
    
    Returns:
    an enumeration of the objects in this DBObjectTable.
    See Also:
    Enumeration
  - contains
```
public boolean contains(DBObject value)
```
    Tests if the DBObject value is contained in this DBObjectTable.
    
    Parameters:
    value - a DBObject to search for.
    
    Throws:
    
    java.lang.NullPointerException - if the value is null.
  - containsKey
```
public boolean containsKey(int key)
```
    Tests if a DBObject with the specified object id is in this DBObjectTable.
    
    Parameters:
    key - possible object id.
  - getNoSync
```
public DBObject getNoSync(int key)
```
    Returns the DBObject with the specified key from this DBObjectTable, or null if no object with that id is in this table.
  - get
```
public DBObject get(int key)
```
    Returns the DBObject with the specified key from this DBObjectTable, or null if no object with that id is in this table.
  - rehash
```
protected void rehash()
```
    Rehashes the contents of the DBObjectTable into a DBObjectTable with a larger capacity. This method is called automatically when the number of keys in the hashtable exceeds this DBObjectTable's capacity and load factor.
  - putNoSync
```
public void putNoSync(DBObject value)
```
    Inserts a DBObject into this DBObjectTable.
    
    This put is not sync'ed, and should only be used with higher level sync provisions.
  - put
```
public void put(DBObject value)
```
    Inserts a DBObject into this DBObjectTable
  - putNoSyncNoRemove
```
public void putNoSyncNoRemove(DBObject value)
```
    Inserts a DBObject into this DBObjectTable.
    
    This put is not sync'ed, and should only be used with higher level sync provisions.
  - removeNoSync
```
public void removeNoSync(int key)
```
    Removes the DBObject with the given id from this DBObjectTable.
  - remove
```
public void remove(int key)
```
    Removes the DBObject with the given id from this DBObjectTable.
  - replaceNoSync
```
public void replaceNoSync(DBObject replaceObject)
```
    Replaces a DBObject in the table in-place without disturbing any Iterators running.
  - clear
```
public void clear()
```
    Clears this DBObjectTable.
  - values
```
public java.util.Collection<DBObject> values()
```
    Returns a non-editable Collection view of this DBObjectTable.

Class DBObjectTable

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

table

count

threshold

loadFactor

modGen

Constructor Detail

DBObjectTable

DBObjectTable

DBObjectTable

Method Detail

getModGen

size

isEmpty

iterator

elements

contains

containsKey

getNoSync

get

rehash

putNoSync

put

putNoSyncNoRemove

removeNoSync

remove

replaceNoSync

clear

values