org.objenesis.ObjenesisBase Maven / Gradle / Ivy
package org.objenesis;
import java.util.HashMap;
import java.util.Map;
import java.util.WeakHashMap;
import org.objenesis.instantiator.ObjectInstantiator;
import org.objenesis.strategy.InstantiatorStrategy;
/**
* Base class to extend if you want to have a class providing your own default strategy. Can also be
* instantiated directly.
*
* @author Henri Tremblay
*/
public class ObjenesisBase implements Objenesis {
/** Strategy used by this Objenesi implementation to create classes */
protected final InstantiatorStrategy strategy;
/** Strategy cache. Key = Class, Value = InstantiatorStrategy */
protected Map cache;
/**
* Constructor allowing to pick a strategy and using cache
*
* @param strategy Strategy to use
*/
public ObjenesisBase(InstantiatorStrategy strategy) {
this(strategy, true);
}
/**
* Flexible constructor allowing to pick the strategy and if caching should be used
*
* @param strategy Strategy to use
* @param useCache If {@link ObjectInstantiator}s should be cached
*/
public ObjenesisBase(InstantiatorStrategy strategy, boolean useCache) {
if(strategy == null) {
throw new IllegalArgumentException("A strategy can't be null");
}
this.strategy = strategy;
this.cache = useCache ? new HashMap() : null;
}
public String toString() {
return getClass().getName() + " using " + strategy.getClass().getName()
+ (cache == null ? " without" : " with") + " caching";
}
/**
* Will create a new object without any constructor being called
*
* @param clazz Class to instantiate
* @return New instance of clazz
*/
public Object newInstance(Class clazz) {
return getInstantiatorOf(clazz).newInstance();
}
/**
* Will pick the best instantiator for the provided class. If you need to create a lot of
* instances from the same class, it is way more efficient to create them from the same
* ObjectInstantiator than calling {@link #newInstance(Class)}.
*
* @param clazz Class to instantiate
* @return Instantiator dedicated to the class
*/
public synchronized ObjectInstantiator getInstantiatorOf(Class clazz) {
if(cache == null) {
return strategy.newInstantiatorOf(clazz);
}
ObjectInstantiator instantiator = (ObjectInstantiator) cache.get(clazz.getName());
if(instantiator == null) {
instantiator = strategy.newInstantiatorOf(clazz);
cache.put(clazz.getName(), instantiator);
}
return instantiator;
}
}