Package org.apache.uima.util.impl
Class OptimizeStrings
- java.lang.Object
-
- org.apache.uima.util.impl.OptimizeStrings
-
public class OptimizeStrings extends Object
Share common underlying char[] among strings: Optimize sets of strings for efficient storage Apply it to a set of strings. Lifecycle: 1) make an instance of this class 2) call .add (String or String[]) for all strings in the set or - skip 1 and 2 and pass in a String [] that can be modified (sorted] 3) call .optimize() 4) call .getString(String) or .getStringArray(String[]) - returns new string objects .updateStringArray(String[]) to replace original Strings .getOffset(String) - returns int offset in some common string .getCommonStringIndex(String) 5) call getCommonStrings to get all the common strings 6) Let the GC collect the instance of this class The strings are added first to a big list, instead of directly to a stringbuilder in order to improve reuse by sorting for longest strings first The commonStrings are kept in an array. There are more than one to support very large amounts, in excess of 2GB. Nulls, passed in as strings, are mostly ignored, but handled appropriately.
-
-
Constructor Summary
Constructors Constructor Description OptimizeStrings(boolean doMeasurement)
OptimizeStrings(boolean doMeasurement, int splitSize)
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description void
add(String s)
null strings not added 0 length strings addedvoid
add(String[] sa)
int
getCommonStringIndex(int index)
String[]
getCommonStrings()
The list of common stringsint
getIndexOrSeqIndex(String s)
int
getOffset(int i)
long
getOffset(String s)
long
getSavedCharsExact()
The number of characters saved - for statistical reporting onlylong
getSavedCharsSubstr()
String
getString(String s)
return a string which is made as a substring of the common stringString[]
getStringArray(String[] sai)
int
getStringIndex(String s)
void
optimize()
Fully checking indexof for every new string is prohibitively expensive We do a partial check - only checking if a string is a substring of the previous onevoid
updateStringArray(String[] sa)
-
-
-
Method Detail
-
getSavedCharsExact
public long getSavedCharsExact()
The number of characters saved - for statistical reporting only- Returns:
- the number of characters saved
-
getSavedCharsSubstr
public long getSavedCharsSubstr()
-
getCommonStrings
public String[] getCommonStrings()
The list of common strings- Returns:
- the list of common strings
-
add
public void add(String s)
null strings not added 0 length strings added- Parameters:
s
- -
-
add
public void add(String[] sa)
-
getStringIndex
public int getStringIndex(String s)
-
getIndexOrSeqIndex
public int getIndexOrSeqIndex(String s)
- Parameters:
s
- must not be null- Returns:
- a (positive or 0) or negative number. If positive, it is the offset in the common string If negative, -v is the index (starting at 1) that sequentially increases, for each new unique string fetched using this method.
-
getString
public String getString(String s)
return a string which is made as a substring of the common string- Parameters:
s
- -- Returns:
- an equal string, made as substring of common string instance equal results return the same string
-
getOffset
public long getOffset(String s)
-
getOffset
public int getOffset(int i)
-
getCommonStringIndex
public int getCommonStringIndex(int index)
- Parameters:
index
- an index (not offset) to the sorted strings,- Returns:
- the index of the segment it belongs to
-
updateStringArray
public void updateStringArray(String[] sa)
-
optimize
public void optimize()
Fully checking indexof for every new string is prohibitively expensive We do a partial check - only checking if a string is a substring of the previous one
-
-