jcp.ch01.basic.CachedFactorizer

package book.jcp.ch01.basic;

import java.math.BigInteger;

public class CachedFactorizer {

    private BigInteger lastNumberBigInteger;
    private BigInteger[] lastFactorsBigIntegers;
    private long hits;
    private long cacheHits;

    public synchronized long getHits() {
        return hits;
    }

    public synchronized double getHitRatio() {
        return (double) cacheHits / (double) hits;
    }

    public void service(int req, int resp) {
        BigInteger i = extractFromRequest(req);
        BigInteger[] newFactors = null;
        synchronized (this) {
            ++hits;
            if (i.equals(lastNumberBigInteger)) {
                ++cacheHits;
                newFactors = lastFactorsBigIntegers.clone();
            }
        }
        if (newFactors == null) {
            newFactors = factor(i);
            synchronized (this) {
                lastNumberBigInteger = i;
                lastFactorsBigIntegers = newFactors.clone();
            }
        }
        encodeIntoResponse(resp, newFactors);
    }

    private BigInteger[] factor(BigInteger i) {
        // TODO Auto-generated method stub
        return null;
    }

    private void encodeIntoResponse(int resp, BigInteger[] factors) {
        // TODO Auto-generated method stub

    }

    private BigInteger extractFromRequest(int req) {
        // TODO Auto-generated method stub
        return null;
    }
}