What are the differences between clearcase and git? How to merge code in Clearcase? What are vobs? What is permgen? Java memory location classification? Which memories will the objects, static variables, instance variables, method variables reside?Refer: http://javapapers.com/core-java/java-jvm-memory-types/ Code review standards? How do you find/resolve Memory leaks? How do you test performance of your developed code? how does garbage collection take place? what if i have a mechanism for doing gc when memory reaches 80%, will all garbage collectable objects be garbage collected? how does gc thread (being daemon thread) impact performance? why string is immutable? how does hashmap work? if two objects have same hashcode then how hashmap knows which object to return? what is the o/p of the following: Map<String, Integer> map = new HashMap<String, Integer>(); a. map.put("abc", 1); map.put("def", 2); map.put("abc", 2); what values does the map hold? b. StringBuffer sb = new StringBuffer("abc"); StringBuffer sb2 = new StringBuffer("xyz"); StringBuffer sb3 = new StringBuffer("abc"); map.put(sb, 1); map.put(sb2, 2); map.put(sb3, 2); what values does the map hold? what is the o/p of the following - will this compile? class A { public void m1() throws FileNotFoundException { } } class B extends A { public void m1() throws IOException { } } What are Entity, stateful, stateless EJBs? EJB related - How to open a transaction in method 1 which invokes method 2? Method 1 has its own transaction and method 2 should also have is own. what are the transaction level attributes in EJB? Hibernate related - how to get the current(callee's) transaction in method-2 which gets invoked from method-1. what is IOC and DI? Is DI same as IOC? what is adv of extjs? how do you make ajax calls in extjs? do you refresh the entire UI or only part of the UI while making the ajax request, since the UI is based on MVC architecture and if model changes the view should render the values entirely. How do you handle IE/chrome compatibility issues? Give example. did you work on css? how do you fix css based issues, keeping browser compatibility in mind? how do you debug javascript errors? do you use firebug/developer tools? do you use any UI testing tools?