Frage im Vorstellungsgespräch bei Infogain

What is the difference between == and .equals()? Explain String, StringBuilder, and StringBuffer. What are wrapper classes in Java? How does garbage collection work in Java? What is the difference between final, finally, and finalize()? Explain the concept of immutability and how to create an immutable class. What is method overloading vs method overriding? What are the access modifiers in Java? What is the difference between HashMap, TreeMap, and LinkedHashMap? Explain fail-fast vs fail-safe iterators.