All Packages This Package Class Hierarchy Class Search Index
Class calypso.util.IDMap
java.lang.Object | +----calypso.util.IDMap
An identifier mapper. This provides a 1-1 map between strings and integers where the strings are unique within the map.
public class IDMap
extends java.lang.Object
{
// Fields 12
private static final int A;
private static final int DEFAULT;
private static final int EMPTY;
private int fCapacity;
private int fCount;
private int[] fHashCodes;
private int fIndexMask;
private Object[] fKeys;
private int fNumStrings;
private int fShift;
private String[] fStrings;
private int[] fValues;
// Constructors 1
public IDMap();
// Methods 11
private int addString(String);
private void grow();
private final int hashCodeForString(String);
private final int hashCodeForStringBuf(StringBuf);
public String idToString(int);
private final boolean keysAreEqual(Object, Object);
public synchronized int stringBufToID(StringBuf);
public synchronized String stringBufToString(StringBuf);
public synchronized int stringToID(String);
public synchronized String stringToString(String);
private int tableIndexFor(Object, int);
}
Fields
• fKeys
private Object[] fKeys
• fHashCodes
private int[] fHashCodes
• fValues
private int[] fValues
• fStrings
private String[] fStrings
• fNumStrings
private int fNumStrings
• fShift
private int fShift
• fIndexMask
private int fIndexMask
• fCount
private int fCount
• fCapacity
private int fCapacity
• A
private static final int A
For the multiplicative hash, choose the golden ratio:A = ((sqrt(5) - 1) / 2) * (1 << 32)ala Knuth...
• EMPTY
private static final int EMPTY
We use EMPTY and REMOVED as special markers in the table. If some poor object returns one of these two values as their hashCode, it is wacked to DEFAULT.
• DEFAULT
private static final int DEFAULT
Constructors
• IDMap
public IDMap()
Methods
• stringToID
public synchronized int stringToID(String aStr)
Given a string, find an id for it. If the string is already present return the old id. Otherwise allocate a new one.
• stringBufToID
public synchronized int stringBufToID(StringBuf aStrBuf)
Given a StringBuf, find an id for it. If the string is already present return the old id. Otherwise allocate a new one.
• stringBufToString
public synchronized String stringBufToString(StringBuf aStrBuf)
• stringToString
public synchronized String stringToString(String aStr)
If the argument string is already present in the map return the original string object. Otherwise, allocate a new id and return the argument string.
• idToString
public String idToString(int aID)
Given an id, return the string it maps to.
• addString
private int addString(String aString)
Add string to the end of the internal strings array. Return the index in the array.
• hashCodeForString
private final int hashCodeForString(String str)
Provide hashcode for a given key
• hashCodeForStringBuf
private final int hashCodeForStringBuf(StringBuf strBuf)
• keysAreEqual
private final boolean keysAreEqual(Object aKey1, Object aKey2)
• tableIndexFor
private int tableIndexFor(Object aKey, int aHash)
Primitive method used internally to find slots in the table. If the key is present in the table, this method will return the index under which it is stored. If the key is not present, then this method will return the index under which it can be put. The caller must look at the hashCode at that index to differentiate between the two possibilities.
• grow
private void grow()
Grows the table by a factor of 2 (or creates it if necessary). All the REMOVED markers go away and the elements are rehashed into the bigger table.
All Packages This Package Class Hierarchy Class Search IndexFreshly brewed Java API Documentation automatically generated with polardoc Version 1.0.4