/*
* Copyright 2002-2016 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.objenesis;
import org.springframework.core.SpringProperties;
import org.springframework.objenesis.instantiator.ObjectInstantiator;
import org.springframework.objenesis.strategy.InstantiatorStrategy;
import org.springframework.objenesis.strategy.StdInstantiatorStrategy;
import org.springframework.util.ConcurrentReferenceHashMap;
Spring-specific variant of ObjenesisStd / ObjenesisBase, providing a cache based on Class keys instead of class names, and allowing for selective use of the cache. Author: Juergen Hoeller See Also: Since: 4.2
/**
* Spring-specific variant of {@link ObjenesisStd} / {@link ObjenesisBase},
* providing a cache based on {@code Class} keys instead of class names,
* and allowing for selective use of the cache.
*
* @author Juergen Hoeller
* @since 4.2
* @see #isWorthTrying()
* @see #newInstance(Class, boolean)
*/
public class SpringObjenesis implements Objenesis {
System property that instructs Spring to ignore Objenesis, not even attempting
to use it. Setting this flag to "true" is equivalent to letting Spring find
out that Objenesis isn't working at runtime, triggering the fallback code path
immediately: Most importantly, this means that all CGLIB AOP proxies will be
created through regular instantiation via a default constructor.
/**
* System property that instructs Spring to ignore Objenesis, not even attempting
* to use it. Setting this flag to "true" is equivalent to letting Spring find
* out that Objenesis isn't working at runtime, triggering the fallback code path
* immediately: Most importantly, this means that all CGLIB AOP proxies will be
* created through regular instantiation via a default constructor.
*/
public static final String IGNORE_OBJENESIS_PROPERTY_NAME = "spring.objenesis.ignore";
private final InstantiatorStrategy strategy;
private final ConcurrentReferenceHashMap<Class<?>, ObjectInstantiator<?>> cache =
new ConcurrentReferenceHashMap<>();
private volatile Boolean worthTrying;
Create a new SpringObjenesis instance with the standard instantiator strategy. /**
* Create a new {@code SpringObjenesis} instance with the
* standard instantiator strategy.
*/
public SpringObjenesis() {
this(null);
}
Create a new SpringObjenesis instance with the given standard instantiator strategy. Params: - strategy – the instantiator strategy to use
/**
* Create a new {@code SpringObjenesis} instance with the
* given standard instantiator strategy.
* @param strategy the instantiator strategy to use
*/
public SpringObjenesis(InstantiatorStrategy strategy) {
this.strategy = (strategy != null ? strategy : new StdInstantiatorStrategy());
// Evaluate the "spring.objenesis.ignore" property upfront...
if (SpringProperties.getFlag(SpringObjenesis.IGNORE_OBJENESIS_PROPERTY_NAME)) {
this.worthTrying = Boolean.FALSE;
}
}
Return whether this Objenesis instance is worth trying for instance creation,
i.e. whether it hasn't been used yet or is known to work.
If the configured Objenesis instantiator strategy has been identified to not work on the current JVM at all or if the "spring.objenesis.ignore" property has been set to "true", this method returns false.
/**
* Return whether this Objenesis instance is worth trying for instance creation,
* i.e. whether it hasn't been used yet or is known to work.
* <p>If the configured Objenesis instantiator strategy has been identified to not
* work on the current JVM at all or if the "spring.objenesis.ignore" property has
* been set to "true", this method returns {@code false}.
*/
public boolean isWorthTrying() {
return (this.worthTrying != Boolean.FALSE);
}
Create a new instance of the given class via Objenesis.
Params: - clazz – the class to create an instance of
- useCache – whether to use the instantiator cache (typically
true but can be set to false e.g. for reloadable classes)
Throws: - ObjenesisException – if instance creation failed
Returns: the new instance (never null)
/**
* Create a new instance of the given class via Objenesis.
* @param clazz the class to create an instance of
* @param useCache whether to use the instantiator cache
* (typically {@code true} but can be set to {@code false}
* e.g. for reloadable classes)
* @return the new instance (never {@code null})
* @throws ObjenesisException if instance creation failed
*/
public <T> T newInstance(Class<T> clazz, boolean useCache) {
if (!useCache) {
return newInstantiatorOf(clazz).newInstance();
}
return getInstantiatorOf(clazz).newInstance();
}
public <T> T newInstance(Class<T> clazz) {
return getInstantiatorOf(clazz).newInstance();
}
@SuppressWarnings("unchecked")
public <T> ObjectInstantiator<T> getInstantiatorOf(Class<T> clazz) {
ObjectInstantiator<?> instantiator = this.cache.get(clazz);
if (instantiator == null) {
ObjectInstantiator<T> newInstantiator = newInstantiatorOf(clazz);
instantiator = this.cache.putIfAbsent(clazz, newInstantiator);
if (instantiator == null) {
instantiator = newInstantiator;
}
}
return (ObjectInstantiator<T>) instantiator;
}
protected <T> ObjectInstantiator<T> newInstantiatorOf(Class<T> clazz) {
Boolean currentWorthTrying = this.worthTrying;
try {
ObjectInstantiator<T> instantiator = this.strategy.newInstantiatorOf(clazz);
if (currentWorthTrying == null) {
this.worthTrying = Boolean.TRUE;
}
return instantiator;
}
catch (ObjenesisException ex) {
if (currentWorthTrying == null) {
Throwable cause = ex.getCause();
if (cause instanceof ClassNotFoundException || cause instanceof IllegalAccessException) {
// Indicates that the chosen instantiation strategy does not work on the given JVM.
// Typically a failure to initialize the default SunReflectionFactoryInstantiator.
// Let's assume that any subsequent attempts to use Objenesis will fail as well...
this.worthTrying = Boolean.FALSE;
}
}
throw ex;
}
catch (NoClassDefFoundError err) {
// Happening on the production version of Google App Engine, coming out of the
// restricted "sun.reflect.ReflectionFactory" class...
if (currentWorthTrying == null) {
this.worthTrying = Boolean.FALSE;
}
throw new ObjenesisException(err);
}
}
}