/Users/jst/src/grafalgo/cpp/dataStructures/hash/HashMap.cpp

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#include "HashMap.h"

namespace grafalgo {

HashMap::HashMap(int n1) : Adt(n1) { makeSpace(n()); };
        
HashMap::~HashMap() { freeSpace(); }

void HashMap::makeSpace(int size) {
        try {
                values = new int[size+1];
                ht = new HashTbl(size); kvx = new SetPair(size);
        } catch (std::bad_alloc e) {
                stringstream ss;
                ss << "HashMap::makeSpace: insufficient space for "
                   << size << "index values";
                string s = ss.str();
                throw OutOfSpaceException(s);
        }
        nn = size;
}

void HashMap::freeSpace() { delete [] values; delete ht; delete kvx; }

void HashMap::resize(int size) {
        freeSpace();
        try { makeSpace(size); } catch(OutOfSpaceException e) {
                string s; s = "HashMap::resize::" + e.toString(s);
                throw OutOfSpaceException(s);
        }
}

void HashMap::expand(int size) {
        if (size <= n()) return;
        HashMap old(this->n()); old.copyFrom(*this);
        resize(size); this->copyFrom(old);
}

void HashMap::clear() {
        while (firstPair() != 0) remove(key(firstPair()));
}

void HashMap::copyFrom(const HashMap& src) {
        if (&src == this) return;
        if (src.n() > n()) resize(src.n());
        else clear();
        for (index x = src.firstPair(); x != 0; x = src.nextPair(x))
                put(src.key(x), src.val(x));
}

// Construct string listing the key,value pairs in the map
string& HashMap::toString(string& s) const {
        stringstream ss; ss << "{";
        bool isFirst = true;
        for (int kvi = kvx->firstIn(); kvi != 0; kvi = kvx->nextIn(kvi)) {
                if (isFirst) isFirst = false;
                else ss << " ";
                ss << "(" << key(kvi) << "," << val(kvi) << ")";
        }
        ss << "}"; s = ss.str(); return s;
}

} // ends namespace