Package org.smooks.engine.delivery.sax.ng.org.apache.xerces.util

Class SoftReferenceSymbolTable

  • public class SoftReferenceSymbolTable
extends SymbolTable
    This symbol table uses SoftReferences to its String entries, which means that table entries that have no references to them can be garbage collected when memory is needed. Thus, in documents with very very large numbers of unique strings, using this SymbolTable will prevent an out of memory error from occurring.
    Version:
    $Id$
    Author:
    Peter McCracken, IBM
    See Also:
    SymbolTable

    • Constructor Detail

      • SoftReferenceSymbolTable

        public SoftReferenceSymbolTable​(int initialCapacity,
                                float loadFactor)
        Constructs a new, empty SymbolTable with the specified initial capacity and the specified load factor.
        Parameters:
        initialCapacity - the initial capacity of the SymbolTable.
        loadFactor - the load factor of the SymbolTable.
        Throws:
        IllegalArgumentException - if the initial capacity is less than zero, or if the load factor is nonpositive.

      • SoftReferenceSymbolTable

        public SoftReferenceSymbolTable​(int initialCapacity)
        Constructs a new, empty SymbolTable with the specified initial capacity and default load factor, which is 0.75.
        Parameters:
        initialCapacity - the initial capacity of the hashtable.
        Throws:
        IllegalArgumentException - if the initial capacity is less than zero.

      • SoftReferenceSymbolTable

        public SoftReferenceSymbolTable()
        Constructs a new, empty SymbolTable with a default initial capacity (101) and load factor, which is 0.75.

    • Method Detail

      • addSymbol

        public String addSymbol​(String symbol)
        Adds the specified symbol to the symbol table and returns a reference to the unique symbol. If the symbol already exists, the previous symbol reference is returned instead, in order guarantee that symbol references remain unique.
        Overrides:
        addSymbol in class SymbolTable
        Parameters:
        symbol - The new symbol.

      • addSymbol

        public String addSymbol​(char[] buffer,
                        int offset,
                        int length)
        Adds the specified symbol to the symbol table and returns a reference to the unique symbol. If the symbol already exists, the previous symbol reference is returned instead, in order guarantee that symbol references remain unique.
        Overrides:
        addSymbol in class SymbolTable
        Parameters:
        buffer - The buffer containing the new symbol.
        offset - The offset into the buffer of the new symbol.
        length - The length of the new symbol in the buffer.

      • rehash

        protected void rehash()
        Increases the capacity of and internally reorganizes this SymbolTable, in order to accommodate and access its entries more efficiently. This method is called automatically when the number of keys in the SymbolTable exceeds this hashtable's capacity and load factor.
        Overrides:
        rehash in class SymbolTable

      • compact

        protected void compact()
        Reduces the capacity of and internally reorganizes this SymbolTable, in order to accommodate and access its entries in a more memory efficient way. This method is called automatically when the number of keys in the SymbolTable drops below 25% of this hashtable's load factor (as a result of SoftReferences which have been cleared).

      • rebalance

        protected void rebalance()
        Randomly selects a new hash function and reorganizes this SymbolTable in order to more evenly distribute its entries across the table. This method is called automatically when the number keys in one of the SymbolTable's buckets exceeds the given collision threshold.
        Overrides:
        rebalance in class SymbolTable

      • containsSymbol

        public boolean containsSymbol​(String symbol)
        Returns true if the symbol table already contains the specified symbol.
        Overrides:
        containsSymbol in class SymbolTable
        Parameters:
        symbol - The symbol to look for.

      • containsSymbol

        public boolean containsSymbol​(char[] buffer,
                              int offset,
                              int length)
        Returns true if the symbol table already contains the specified symbol.
        Overrides:
        containsSymbol in class SymbolTable
        Parameters:
        buffer - The buffer containing the symbol to look for.
        offset - The offset into the buffer.
        length - The length of the symbol in the buffer.