| java.lang.Object
 oscript.util.OpenHashSymbolTable
| OpenHashSymbolTable | | public class OpenHashSymbolTable implements SymbolTable,java.io.Externalizable(Code) | | A symbol table implementation based on a open hash map, using double
hashing as a strategy to avoid collisions. Double hasing uses two hash
functions to compute an index into the table:
Idx(i,k) := H1(k) + i * H2(k)
where for a given key k, i is incremented from
0 until an unused table slot is found.
Threading note: this class is not synchronized, but is designed to
save to read from multiple threads, while write from a single thread
context (at a time).
author:
Rob Clark (rob@ti.com)
version:
1.0 |
| OpenHashSymbolTable | | public OpenHashSymbolTable()(Code) | | Class Constructor.
|
| OpenHashSymbolTable | | public OpenHashSymbolTable(int capacity, float load)(Code) | | Class Constructor.
Parameters:
capacity - the initial capacity
Parameters:
load - the loading factor |
| create | | public int create(int id)(Code) | | Get the index that the specified symbol maps to, and create a new one
if a mapping does not already exist. If a new mapping is created,
it's value is the next successive array index, ie. the the previous
array index plus one. The first mapping created has the value zero.
Parameters:
id - the id of the symbol to get a mapping for an index |
| get | | final public int get(int id)(Code) | | Get the index that the specified symbol maps to.
Parameters:
id - the id of the symbol to get a mapping for an index, or -1 if no mapping exists for thespecified symbol |
| getLoad | | public float getLoad()(Code) | | |
| getStats | | final public static synchronized String getStats()(Code) | | |
| size | | public int size()(Code) | | The number of mappings that exist in this table.
the number of mappings in the table |
| symbols | | public synchronized java.util.Iterator symbols()(Code) | | Return an iteration of the keys (symbols) into this table. To conform to
the
java.util.Iterator interface, each symbol is wrapped (boxed)
in a
Integer .
an iteration of symbols that are keys into this table |
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