SmallMap

java.lang.Object
- org.h2.util.SmallMap

```
public class SmallMap
extends java.lang.Object
```
A simple hash table with an optimization for the last recently used object.

Field Summary

Fields
Modifier and Type	Field	Description
`private java.lang.Object`	`cache`
`private int`	`cacheId`
`private int`	`lastId`
`private java.util.HashMap<java.lang.Integer,java.lang.Object>`	`map`
`private int`	`maxElements`

Constructor Summary

Constructors
Constructor Description

SmallMap(int maxElements)
Create a map with the given maximum number of entries.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`int`	`addObject(int id, java.lang.Object o)`	Add an object to the map.
`void`	`freeObject(int id)`	Remove an object from the map.
`java.lang.Object`	`getObject(int id, boolean ifAvailable)`	Get an object from the map if it is stored.

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

- Field Detail
  - map
```
private final java.util.HashMap<java.lang.Integer,java.lang.Object> map
```
  - cache
```
private java.lang.Object cache
```
  - cacheId
```
private int cacheId
```
  - lastId
```
private int lastId
```
  - maxElements
```
private final int maxElements
```
- Constructor Detail
  - SmallMap
```
public SmallMap(int maxElements)
```
    Create a map with the given maximum number of entries.
    
    Parameters:
    
    maxElements - the maximum number of entries
- Method Detail
  - addObject
```
public int addObject(int id,
                     java.lang.Object o)
```
    Add an object to the map. If the size of the map is larger than twice the maximum size, objects with a low id are removed.
    
    Parameters:
    
    id - the object id
    
    o - the object
    
    Returns:
    
    the id
  - freeObject
```
public void freeObject(int id)
```
    Remove an object from the map.
    
    Parameters:
    
    id - the id of the object to remove
  - getObject
```
public java.lang.Object getObject(int id,
                                  boolean ifAvailable)
```
    Get an object from the map if it is stored.
    
    Parameters:
    
    id - the id of the object
    
    ifAvailable - only return it if available, otherwise return null
    
    Returns:
    
    the object or null
    
    Throws:
    
    DbException - if isAvailable is false and the object has not been found