1 package book.jcp.ch01.basic; 2 3 import java.math.BigInteger; 4 5 public class CachedFactorizer { 6 7 private BigInteger lastNumberBigInteger; 8 private BigInteger[] lastFactorsBigIntegers; 9 private long hits;10 private long cacheHits;11 12 public synchronized long getHits() {13 return hits;14 }15 16 public synchronized double getHitRatio() {17 return (double) cacheHits / (double) hits;18 }19 20 public void service(int req, int resp) {21 BigInteger i = extractFromRequest(req);22 BigInteger[] newFactors = null;23 synchronized (this) {24 ++hits;25 if (i.equals(lastNumberBigInteger)) {26 ++cacheHits;27 newFactors = lastFactorsBigIntegers.clone();28 }29 }30 if (newFactors == null) {31 newFactors = factor(i);32 synchronized (this) {33 lastNumberBigInteger = i;34 lastFactorsBigIntegers = newFactors.clone();35 }36 }37 encodeIntoResponse(resp, newFactors);38 }39 40 private BigInteger[] factor(BigInteger i) {41 // TODO Auto-generated method stub42 return null;43 }44 45 private void encodeIntoResponse(int resp, BigInteger[] factors) {46 // TODO Auto-generated method stub47 48 }49 50 private BigInteger extractFromRequest(int req) {51 // TODO Auto-generated method stub52 return null;53 }54 }
JCP. ch01.basic. cachedfactorizer