Java Interview Questions - Page 2
Answer: parsers are fundamental xml components, a bridge between XML documents and applications that process that XML. The parser is responsible for handling xml syntax, checking the contents of the document against constraints established in a DTD or Schema.
Question: What is a platform?
Answer: A platform is the hardware or software environment
in which a program runs. Most platforms can be described as a combination of
the operating system and hardware, like Windows 2000/XP, Linux, Solaris, and
MacOS.
Question: What is the main difference between Java platform and other platforms?
Answer: The Java platform differs from most other platforms in that it's a
software-only platform that runs on top of other hardware-based platforms.
The Java platform has two components:
1. The Java Virtual Machine (Java VM)
2. The Java Application Programming Interface (Java API)
Question: What is the Java Virtual Machine?
Answer: The Java Virtual Machine is a
software that can be ported onto various hardware-based platforms.
Question: What is the Java API?
Answer: The Java API is a large collection of ready-made
software components that provide many useful capabilities, such as graphical
user interface (GUI) widgets.
Question: What is the package?
Answer: The package is a Java namespace or part of Java
libraries. The Java API is grouped into libraries of related classes and
interfaces; these libraries are known as packages.
Question: What is native code?
Answer: The native code is code that after you compile
it, the compiled code runs on a specific hardware platform.
Question: Is Java code slower than native code?
Answer: Not really. As a
platform-independent environment, the Java platform can be a bit slower than
native code. However, smart compilers, well-tuned interpreters, and
just-in-time bytecode compilers can bring performance close to that of
native code without threatening portability.
Question: What is the serialization?
Answer: The serialization is a kind of mechanism
that makes a class or a bean persistence by having its properties or fields
and state information saved and restored to and from storage.
Question: How to make a class or a bean
serializable?
Answer: By implementing either the
java.io.Serializable interface, or the java.io.Externalizable interface. As
long as one class in a class's inheritance hierarchy implements Serializable
or Externalizable, that class is serializable.