package net.jcip.examples;

import java.math.BigInteger;

import javax.servlet.*;

import net.jcip.annotations.*;

/**

* Factorizer

* <p/>

* Factorizing servlet that caches results using Memoizer

*

* @author Brian Goetz and Tim Peierls

*/

@ThreadSafe

public class Factorizer extends GenericServlet implements Servlet {

private final Computable<BigInteger, BigInteger[]> c =

new Computable<BigInteger, BigInteger[]>() {

public BigInteger[] compute(BigInteger arg) {

return factor(arg);

}

};

private final Computable<BigInteger, BigInteger[]> cache

= new Memoizer<BigInteger, BigInteger[]>(c);

public void service(ServletRequest req,

ServletResponse resp) {

try {

BigInteger i = extractFromRequest(req);

encodeIntoResponse(resp, cache.compute(i));

} catch (InterruptedException e) {

encodeError(resp, "factorization interrupted");

}

}

void encodeIntoResponse(ServletResponse resp, BigInteger[] factors) {

}

void encodeError(ServletResponse resp, String errorString) {

}

BigInteger extractFromRequest(ServletRequest req) {

return new BigInteger("7");

}

BigInteger[] factor(BigInteger i) {

// Doesn't really factor

return new BigInteger[]{i};

}

}