Question

What are the possibilities of doing deep object cloning without Java reflection? I have used Object cloning libraries that use reflection but AppEngine does not allow to do that.

So my existing application that worked with Tomcat not does not work.

Update:

Dozer library seems to be the best bet:

Mapper mapper = new DozerBeanMapper();
DestinationObject destObject =  mapper.map(sourceObject, DestinationObject.class);

Question would be if I don’t need custom mapping can I just do the above as it is?

For example:

Cat cat = new Cat();

Mapper mapper = new DozerBeanMapper();
Cat newCat =  mapper.map(cat, Cat.class);

Update:

When I run my app with Dozer I get this error:

Caused by: java.lang.NoSuchMethodError: org.apache.commons.lang.StringUtils.contains(Ljava/lang/String;Ljava/lang/String;)Z
    at org.dozer.util.ResourceLoader.getResource(ResourceLoader.java:53)
    at org.dozer.util.DefaultClassLoader.loadResource(DefaultClassLoader.java:44)
    at org.dozer.config.GlobalSettings.loadGlobalSettings(GlobalSettings.java:116)
    at org.dozer.config.GlobalSettings.<init>(GlobalSettings.java:67)
    at org.dozer.config.GlobalSettings.<clinit>(GlobalSettings.java:46)

Looks like I am missing something, although I added Dozer using Maven.

Answer 1

Have you considered using Dozer?

[from their website]

Dozer is a Java Bean to Java Bean mapper that recursively copies data
from one object to another. Typically, these Java Beans will be of
different complex types.

Dozer supports simple property mapping, complex type mapping,
bi-directional mapping, implicit-explicit mapping, as well as
recursive mapping. This includes mapping collection attributes that
also need mapping at the element level.

Dozer not only supports mapping between attribute names, but also
automatically converting between types. Most conversion scenarios are
supported out of the box, but Dozer also allows you to specify custom
conversions via XML.