org.togglz.core.proxy

Class ByteBuddyProxyFactory

java.lang.Object

org.togglz.core.proxy.ByteBuddyProxyFactory

public class ByteBuddyProxyFactory
extends Object

Produces switching proxy implementations which delegate invocation to one of two objects depending on the state of the specified Feature.

Generated Code

Assuming a user interface ...

 public interface UserDAO { User findById(int id); }

... proxyFor(org.togglz.core.Feature, java.lang.Class<? super T>, T, T) will generate classes equivalent to the following source code ...

 public class X extends TogglzSwitchable implements UserDAO {
   public X(FeatureManager featureManager, Feature feature, UserDAO active, UserDAO inactive) {
     super(featureManager, feature, active, inactive);
   }
   public User findById(int id) {
     super.checkTogglzState();
     return delegate.findById(id);
   }
   public String toString() {
     super.checkTogglzState();
     return delegate.toString();
   }
 } 

Active and Passive mode

In "active" proxies, Feature state is checked as part of every method call which is invisible but also quite slow. It may also be functionally dangerous if the implementations are stateful and should not flipped in the middle of a "session".

For these cases passiveProxyFor(...) will generate classes that never check the feature state themselves. To be updated they must be passed to TogglzSwitchable.update(Object).

Performance

Following gives approximate invocation overhead of using a Feature-controlled proxy vs direct calls.

Direct Call	100%
Passive ByteBuddy Proxy	70%
Active ByteBuddy Proxy	15%
JDK Proxy	10%

See Also:

TogglzSwitchable

Constructor Summary

Constructors

Constructor and Description
ByteBuddyProxyFactory()

Method Summary

Modifier and Type	Method and Description
static <T> T	passiveProxyFor(Feature feature, Class<? super T> interfaceClass, T active, T inactive) Generate a passive Feature proxy.
static <T> T	passiveProxyFor(Feature feature, Class<? super T> interfaceClass, T active, T inactive, FeatureManager featureManager) Generate a passive Feature proxy.
static <T> T	proxyFor(Feature feature, Class<? super T> interfaceClass, T active, T inactive) Generate an active Feature proxy.
static <T> T	proxyFor(Feature feature, Class<? super T> interfaceClass, T active, T inactive, FeatureManager featureManager) Generate an active Feature proxy.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ByteBuddyProxyFactory

public ByteBuddyProxyFactory()

Method Detail

passiveProxyFor

public static <T> T passiveProxyFor(Feature feature,
                                    Class<? super T> interfaceClass,
                                    T active,
                                    T inactive)

Generate a passive Feature proxy.

See Also:

ByteBuddyProxyFactory

passiveProxyFor

public static <T> T passiveProxyFor(Feature feature,
                                    Class<? super T> interfaceClass,
                                    T active,
                                    T inactive,
                                    FeatureManager featureManager)

Generate a passive Feature proxy.

See Also:

ByteBuddyProxyFactory

proxyFor

public static <T> T proxyFor(Feature feature,
                             Class<? super T> interfaceClass,
                             T active,
                             T inactive)

Generate an active Feature proxy.

See Also:

ByteBuddyProxyFactory

proxyFor

public static <T> T proxyFor(Feature feature,
                             Class<? super T> interfaceClass,
                             T active,
                             T inactive,
                             FeatureManager featureManager)

Generate an active Feature proxy.

See Also:

ByteBuddyProxyFactory