java common storage options without db or filesystem

Try to use POJO. Then store all your POJO in a List or a Map.

e.g.

//this is your pojo public class User{ private String name; private int age; public void setName(String name){ this.name = name; } public String getName(){ return this.name; } public void setAge(int age){ this.age = age; } public int getAge(){ return this.age; } } public class TestUser{ public static void main(String args[]){ //to populate record, create object user User user1 = new User(); user1.setName = "name1"; user1.setAge = "20";//then so on //after creating object, store it in a <a href="http://tutorials.jenkov.com/java-collections/index.html"collection</a>. Depends on what you want. List<User> myList = new ArrayList<User>(); //then add it to your collection myList.add(user1); //and so on //you can access now your record on your list } } 

you can use hsql db jdbc driver which has support for creating a in-memory database checkout hsql db documentation for in-memory db support

You can use cache like Memcached.

or you can use in-memory database like HSqlDB.

I would suggest you to use Caches (Oracle Coherence , simple Map) there are many option available. If you want to persist the data for permanently then i don't thing any other option than Database/Filesystem.

Caching

• Ehcache
• Oracle Coherence
• JCS