@Cacheable(value="bookCache", key="isbn")
public Book findBook(ISBN isbn, boolean checkWarehouse, boolean includeUsed)

System.out.println( Objects.hash("someisbn", new Integer(109), new Integer(434)));
    System.out.println( Objects.hash("someisbn", new Integer(110), new Integer(403)));

@Cacheable(value="books", key="T(someType).hash(#isbn)")
public Book findBook(ISBN isbn, boolean checkWarehouse, boolean includeUsed)

@Cacheable(value="bookCache",
  key="{ #root.methodName, #isbn?.id, #checkWarehouse }")
public Book findBook(ISBN isbn, boolean checkWarehouse)
...

@Cacheable(value="bookCache",
  key="{ #root.methodName, #asin, #checkWarehouse }")
public Book findBookByAmazonId(String asin, boolean checkWarehouse)
...

<cache:annotation-driven mode="..." key-generator="cacheKeyGenerator" />
<bean id="cacheKeyGenerator" class="net.example.cache.CacheKeyGenerator" />

public class CacheKeyGenerator
  implements org.springframework.cache.interceptor.KeyGenerator {

    @Override
    public Object generate(final Object target, final Method method,
      final Object... params) {

        final List<Object> key = new ArrayList<>();
        key.add(method.getDeclaringClass().getName());
        key.add(method.getName());

        for (final Object o : params) {
            key.add(o);
        }
        return key;
    }
}

@Cacheable(value="bookCache", key="T(java.util.Objects).hash(#p0,#p1, #p2)")

@Cacheable(value="bookCache", key="#checkwarehouse.toString().append(#isbn.toString())")

@Cacheable(value="bookCache", key="isbn + '_' + checkWarehouse + '_' + includeUsed")