// Copyright (c) 2003-2014, Jodd Team (jodd.org). All Rights Reserved.
package jodd.petite;
import jodd.petite.scope.Scope;
import jodd.proxetta.ProxyAspect;
import jodd.proxetta.impl.ProxyProxetta;
import jodd.proxetta.impl.ProxyProxettaBuilder;
import jodd.proxetta.pointcuts.AllMethodsPointcut;
import jodd.log.Logger;
import jodd.log.LoggerFactory;
import java.lang.reflect.Field;
import java.util.HashMap;
import java.util.Map;
/**
* Manager for mixing scopes.
* 'Mixed scopes' is the situation when 'smaller' scope
* is injected into the 'bigger' scope. Trivial example
* is when <b>prototype</b> scoped bean is injected into
* <b>singleton</b> bean.
* <p>
* Mixed scopes are handled using smart factory/proxy-wrapper singletons
* instead of 'smaller' scoped beans. On each method call of
* wrapped factory, smaller scoped bean will be looked up and
* that instance will be used for passing by the method call.
* <p>
* Manager also has to determine if scope combination is candidate for
* mixed scopes.
*/
public class ScopedProxyManager {
private static final Logger log = LoggerFactory.getLogger(ScopedProxyManager.class);
protected ProxyAspect aspect = new ProxyAspect(ScopedProxyAdvice.class, new AllMethodsPointcut());
protected Map<Class, Class> proxyClasses = new HashMap<Class, Class>();
protected Map<String, Object> proxies = new HashMap<String, Object>();
public ScopedProxyManager() {
log.debug("ScopedProxyManager created");
}
/**
* Returns scoped proxy bean if injection scopes are mixed on some injection point.
* May return <code>null</code> if mixing scopes is not detected.
*/
public Object lookupValue(PetiteContainer petiteContainer, BeanDefinition targetBeanDefinition, BeanDefinition refBeanDefinition) {
Scope targetScope = targetBeanDefinition.scope;
Scope refBeanScope = refBeanDefinition.scope;
boolean detectMixedScopes = petiteContainer.getConfig().isDetectMixedScopes();
boolean wireScopedProxy = petiteContainer.getConfig().isWireScopedProxy();
// when target scope is null then all beans can be injected into it
// similar to prototype scope
if (targetScope != null && targetScope.accept(refBeanScope) == false) {
if (wireScopedProxy == false) {
if (detectMixedScopes) {
throw new PetiteException(createMixingMessage(targetBeanDefinition, refBeanDefinition));
}
return null;
}
if (detectMixedScopes) {
if (log.isWarnEnabled()) {
log.warn(createMixingMessage(targetBeanDefinition, refBeanDefinition));
}
} else {
if (log.isDebugEnabled()) {
log.debug(createMixingMessage(targetBeanDefinition, refBeanDefinition));
}
}
String scopedProxyBeanName = refBeanDefinition.name;
Object proxy = proxies.get(scopedProxyBeanName);
if (proxy == null) {
proxy = createScopedProxyBean(petiteContainer, refBeanDefinition);
proxies.put(scopedProxyBeanName, proxy);
}
return proxy;
}
return null;
}
/**
* Creates mixed scope message.
*/
protected String createMixingMessage(BeanDefinition targetBeanDefinition, BeanDefinition refBeanDefinition) {
return "Scopes mixing detected: " +
refBeanDefinition.name + "@" + refBeanDefinition.scope.getClass().getSimpleName() + " -> " +
targetBeanDefinition.name + "@" + targetBeanDefinition.scope.getClass().getSimpleName();
}
/**
* Creates scoped proxy bean for given bean definition.
*/
protected Object createScopedProxyBean(PetiteContainer petiteContainer, BeanDefinition refBeanDefinition) {
Class beanType = refBeanDefinition.type;
Class proxyClass = proxyClasses.get(beanType);
if (proxyClass == null) {
// create proxy class only once
ProxyProxetta proxetta = ProxyProxetta.withAspects(aspect);
proxetta.setClassNameSuffix("$ScopedProxy");
proxetta.setVariableClassName(true);
ProxyProxettaBuilder builder = proxetta.builder(beanType);
proxyClass = builder.define();
proxyClasses.put(beanType, proxyClass);
}
Object proxy;
try {
proxy = proxyClass.newInstance();
Field field = proxyClass.getField("$__petiteContainer$0");
field.set(proxy, petiteContainer);
field = proxyClass.getField("$__name$0");
field.set(proxy, refBeanDefinition.name);
} catch (Exception ex) {
throw new PetiteException(ex);
}
return proxy;
}
}