FileDocCategorySizeDatePackage
Str2ID.javaAPI DocphoneME MR2 API (J2ME)5427Wed May 02 17:59:48 BST 2007jcc

Str2ID

public class Str2ID extends Object

Fields Summary
public int
hashTableSize
public int
used
public int
baseId
public Str2ID
next
public components.UnicodeConstant[]
strings
public components.StringConstant[]
parameters
public int[]
hashbits
boolean
locked
public static final int
DEFAULT_hashTableSize
int
overflowPoint
public static Str2ID
sigHash
Constructors Summary
public Str2ID()


       
        this(DEFAULT_hashTableSize, true);
public Str2ID(int size)

 
        this(size, false);
private Str2ID(int size, boolean knownPrime)

 
        if (!knownPrime) { 
	    size |= 1;
	    while (!isPrime(size))
	        size += 2;
	}
	hashTableSize = size;
	strings = new UnicodeConstant[size];
	hashbits = new int[size];
	overflowPoint = (int)(hashTableSize * 0.8);
Methods Summary
public intgetID(components.UnicodeConstant str, components.StringConstant parameter)

	Str2ID head = this;
	int index;
	int hash = hashString(str.string);
	int phash = hash & 0x7fffffff;
	int secondaryHash = (hash & 7) + 1;

	Str2ID chain = head;
	for ( ; ; ) {
	    index = chain.unsignedMod(hash);
	    while (chain.strings[index] != null) {
		if ((chain.hashbits[index] == phash) &&
		    chain.strings[index].string.equals(str.string)) {
		    // We found the string, calculate the ID
		    return chain.baseId + index;
		}
		index -= secondaryHash;
		if (index < 0) {
		    index += chain.hashTableSize;
		}
	    }

	    // Didn't find the string in this chain. . . .
	    if (chain.next == null) { 
	        break;
	    } else { 
	        chain = chain.next;
	    }
	}

	if (locked) { 
	    throw new NullPointerException(
		Localizer.getString("str2id.attempting_to_add_to_table_when_locked", str));

	}
	if (chain.used >= chain.overflowPoint) {
	    chain.next = new Str2ID();
	    chain.next.baseId = chain.baseId + chain.hashTableSize;
	    chain = chain.next;
	    index = chain.unsignedMod(hash);
	}

	chain.strings[index] = str;
	chain.hashbits[index] = phash;
	if (parameter != null ){
	    if ( chain.parameters == null ){
		chain.parameters = new StringConstant[chain.hashTableSize];
	    }
	    chain.parameters[index] = parameter;
	}
	chain.used++;
	return chain.baseId + index;
public intgetID(java.lang.String str)

	return getID( new UnicodeConstant( str ), (StringConstant)null );
public intgetID(components.UnicodeConstant name, components.UnicodeConstant sig)

	return (getID( name, (StringConstant)null) << 16) + getID( sig, (StringConstant)null);
public intgetID(java.lang.String name, java.lang.String sig)

	return (getID(name) << 16) + getID(sig);
static inthashString(java.lang.String str)

	int result = 0;
	for (int i = 0; i < str.length(); i++) {
	    result = result * 37 + (int) str.charAt(i);
	}

	return result;
static booleanisPrime(int n)

        if ((n % 2) == 0)
	    return false;
	int sqrt = (int) Math.sqrt(n);
	for (int i = 3; i <= sqrt; i += 2) { 
	    if ((n % i) == 0)
	        return false;
	}
	return true;
public jcc.Str2IDrehash()

        Str2ID newchain, chain;
	int count = 0;
	for (chain = this; chain != null; chain = chain.next) {
	    count += chain.used;
	}
	newchain = new Str2ID((int)Math.ceil(1.25 * count));

	for (chain = this; chain != null; chain = chain.next) {
	    UnicodeConstant strings[] = chain.strings;
	    StringConstant  parameters[] = chain.parameters;
	    for (int i = chain.hashTableSize; --i >= 0; ) { 
	        UnicodeConstant string = strings[i];
		if (string != null) 
		    newchain.getID(string, parameters == null ? null : parameters[i]);
	    }
	}
	return newchain;
public voidsetLocked(boolean lock)

 
        this.locked = lock;
intunsignedMod(int val)


    // Treat val as an unsigned quantity and do the MOD operation
       
	if (val >= 0) {
	    return val % hashTableSize;
	} else {
	    return (int)(((long)val&0xffffffffL) % (long)hashTableSize);
	}