Package org.apache.xml.dtm.ref
Class CustomStringPool
- java.lang.Object
-
- org.apache.xml.dtm.ref.DTMStringPool
-
- org.apache.xml.dtm.ref.CustomStringPool
-
public class CustomStringPool extends DTMStringPool
CustomStringPool is an example of appliction provided data structure for a DTM implementation to hold symbol references, e.g. elelment names. It will follow the DTMDStringPool interface and use two simple methods indexToString(int i) and stringToIndex(Sring s) to map between a set of string values and a set of integer index values. Therefore, an application may improve DTM processing speed by substituting the DTM symbol resolution tables with application specific quick symbol resolution tables.
%REVIEW% The only difference between this an DTMStringPool seems to be that it uses a java.lang.Hashtable full of Integers rather than implementing its own hashing. Joe deliberately avoided that approach when writing DTMStringPool, since it is both much more memory-hungry and probably slower -- especially in JDK 1.1.x, where Hashtable is synchronized. We need to either justify this implementation or discard it. %REVIEW% Xalan-J has dropped support for 1.1.x and we can now use the colletion classes in 1.2, such as java.util.HashMap which is similar to java.util.Hashtable but not synchronized. For performance reasons one could change m_stringToInt to be a HashMap, but is it OK to do that? Are such CustomStringPool objects already used in a thread-safe way?Status: In progress, under discussion.
-
-
Field Summary
Fields Modifier and Type Field Description static int
NULL
-
Constructor Summary
Constructors Constructor Description CustomStringPool()
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description java.lang.String
indexToString(int i)
void
removeAllElements()
int
stringToIndex(java.lang.String s)
-
Methods inherited from class org.apache.xml.dtm.ref.DTMStringPool
main
-
-
-
-
Field Detail
-
NULL
public static final int NULL
- See Also:
- Constant Field Values
-
-
Method Detail
-
removeAllElements
public void removeAllElements()
- Overrides:
removeAllElements
in classDTMStringPool
-
indexToString
public java.lang.String indexToString(int i) throws java.lang.ArrayIndexOutOfBoundsException
- Overrides:
indexToString
in classDTMStringPool
- Returns:
- string whose value is uniquely identified by this integer index.
- Throws:
java.lang.ArrayIndexOutOfBoundsException
- if index doesn't map to a string.
-
stringToIndex
public int stringToIndex(java.lang.String s)
- Overrides:
stringToIndex
in classDTMStringPool
- Returns:
- integer index uniquely identifying the value of this string.
-
-