symbolOop SymbolTable::lookup(int index, const char* name,
int len, unsigned int hash) {
for (HashtableEntry* e = bucket(index); e != NULL; e = e->next()) {
if (e->hash() == hash) {
symbolOop sym = symbolOop(e->literal());
if (sym->equals(name, len)) {
return sym;
}
}
}
return NULL;
}
// Remove unreferenced symbols from the symbol table
// This is done late during GC.
void SymbolTable::unlink() {
int removed = 0;
int total = 0;
size_t memory_total = 0;
for (int i = 0; i < the_table()->table_size(); ++i) {
HashtableEntry<Symbol*, mtSymbol>** p = the_table()->bucket_addr(i);
HashtableEntry<Symbol*, mtSymbol>* entry = the_table()->bucket(i);
while (entry != NULL) {
// Shared entries are normally at the end of the bucket and if we run into
// a shared entry, then there is nothing more to remove. However, if we
// have rehashed the table, then the shared entries are no longer at the
// end of the bucket.
if (entry->is_shared() && !use_alternate_hashcode()) {
break;
}
Symbol* s = entry->literal();
memory_total += s->object_size();
total++;
assert(s != NULL, "just checking");
// If reference count is zero, remove.
if (s->refcount() == 0) {
assert(!entry->is_shared(), "shared entries should be kept live");
delete s;
removed++;
*p = entry->next();
the_table()->free_entry(entry);
} else {
p = entry->next_addr();
}
// get next entry
entry = (HashtableEntry<Symbol*, mtSymbol>*)HashtableEntry<Symbol*, mtSymbol>::make_ptr(*p);
}
}
symbols_removed += removed;
symbols_counted += total;
// Exclude printing for normal PrintGCDetails because people parse
// this output.
if (PrintGCDetails && Verbose && WizardMode) {
gclog_or_tty->print(" [Symbols=%d size=" SIZE_FORMAT "K] ", total,
(memory_total*HeapWordSize)/1024);
}
}
Symbol* SymbolTable::lookup(int index, const char* name,
int len, unsigned int hash) {
int count = 0;
for (HashtableEntry<Symbol*, mtSymbol>* e = bucket(index); e != NULL; e = e->next()) {
count++; // count all entries in this bucket, not just ones with same hash
if (e->hash() == hash) {
Symbol* sym = e->literal();
if (sym->equals(name, len)) {
// something is referencing this symbol now.
sym->increment_refcount();
return sym;
}
}
}
// If the bucket size is too deep check if this hash code is insufficient.
if (count >= BasicHashtable<mtSymbol>::rehash_count && !needs_rehashing()) {
_needs_rehashing = check_rehash_table(count);
}
return NULL;
}