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Java class parser

I am parsing all the class files in a jar via Objectweb asm (http://forge.ow2.org/projects/asm/). The idea is to parse and store (and use for something later) all the public/protected methods and fields in each class file. It is working as expected. What I dont get is the list of methods, declared by the interface and those inherited from superclasses and superinterfaces. Is there a smart parser available that would give me the above list?
I could load the class file and then use java.lang.Class object to get what I need. But loading classes might fail because of dependencies. I would rather parse and get that info.

The data you want is simply not there. Inherited members are implicit: you only have the names of the class and interfaces where they can be looked for, and you need to parse the corresponding class files.

You can simply do this :
Class superclass = aClass.getSuperclass();
aClass.getClass().getInterfaces();
aClass.getClass().getMethods();

Serializing jackson generated classes

I use jackson (via resteasy) to convert json to a Java object. I've only defined an interface for the object and jackson generates the implementation automatically. Great!
Now I'm trying to save the object and restore it later. My interface extends Serializable, so my datastore saves it without complaint. When it comes time to load it later, though, the generated class definition is nowhere to be found. I get
java.lang.ClassNotFoundException: org.codehaus.jackson.generated.my.class.name
What are my options for saving and loading objects with class definitions generated by Jackson?

Maybe serialize POJO as java.util.Map instead? JDK serialization is tightly bound to concrete classes, so it may not work well with Jackson's abstract type materialization (I assume you are using "Mr Bean" module).

How to handle various concrete implementations of an Interface with JAX-B

I have a class that any I need to marshal to XML.
#XmlRootElement
#XmlAccessorType(XmlAccessType.FIELD)
public class ClassToBeMarshalled {
public Interface object;
}
The Interface is implemented by a lot of concrete classes and most of them are vendor specific whose source code I don't have access to.
So my problem is:
If I try to marshal that class, JAX-B will complain that the current concrete implementation of Interface is not known in the context - In another words, the concrete class was not loaded into the context by calling JAXBContext.newInstance providing the current implementation.
The most common ways to sort out that problem are:
1) Use XMLSeeAlso - not a viable option as there are a lot of concrete classes
2) Annotate each class with #XmlRootElement - not a viable option as I don't have access to all the classes
Does anyone know a way to make JAX-B load the concrete class into its context as the need arises?
Thanks.
P.S.: I'm using JAX-B RI

You could mark your object as #XmlAnyElement(InterfaceHandler.class) where InterfaceHandler is a DomHandler capable of translating between a DOM representation and the actual implementing classes. That handler should probably store the class name when marshalling, and use that class name to create the instance when unmarshalling. It might either configure the instance manually, perhaps using some helper classes designed to work with beans, or it might use another jaxb context which includes that specifically named class and will handle that object with all its nested children.
Also have a look at the #XmlElementRef annotation. I fear that in order to make this work properly, you'd have to at least know all the implementing classes at compile time, but perhaps there is a way you can make this work for you as well, with less trouble than the generic solution outlined in the previous paragraph.

Generate additional custom method with jaxb-xjc

There's some way to generate a custom method within an class generated with JAXB.
I search around tutorials, including oracle's tutorial, but I didn't find clear instructions how can I custom methods to a generated class described on XML Schema.

I have found the following to be the best way to add custom behavior:
https://javaee.github.io/jaxb-v2/doc/user-guide/ch03.html#compiling-xml-schema-adding-behaviors
You can implement the custom behavior for a JAXB generated class BaseType in a custom class BaseTypeExt that extends the JAXB generated class BaseType.
You also tell JAXB to use your extended class BaseTypeExt (instead of the BaseType class it extends) as the base class for all classes that normally would have extended the BaseType class.
I used this successfully to override the toString() method in my generated class BaseType.
This seems simpler than writing an XJC plugin.

You can write an XJC plugin:
http://weblogs.java.net/blog/kohsuke/archive/2005/06/writing_a_plugi.html

Marshalling arraylist of abstract class in JAXB

I have a Java application that I want to save the data in XML instead of a database.
We decided to go with JAXB and instead of generating files based on the schema, we just added annotations to our Java files.
The issue we are running into is that we have an ArrayList of an abstract class called Node. A Node has subclasses of either Module or ScreenImage. When we marshall the arraylist, it doesn't save the type. Such as:
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:type="Module"
Does JAXB support elements that are abstract?
How do I get JAXB to save the type, so that I'm able to unmarshall it?

axtavt's suggestion is fine. I just want to add another approach. You could make use of #XmlSeeAlso, where you can declare other classes that should defined and visible to JAXBContext. You only have to make sure to declare the annotation within a class that is already visible to JAXBContext.
e.g.:
#XmlRootElement
#XmlSeeAlso({Node.class, Module.class, ScreenImage.class})
class SomeContent {
private List<Node> nodes;
///... accessors
}

It should work fine.
Note that if your Module and ScreenImage are not statically accessible from the bound classes (i.e. the classes specified in JAXBContext.newInstance(...)), they should be bound explicitly (add them to the JAXBContext.newInstance(...) parameters).