Java database Placement Papers Interview Questions

• What is the difference between an Abstract class and Interface ?
  
• What is user defined exception ?
  
  • What do you know about the garbage collector ?
    
• What is the difference between C++ & Java ?
  
• Explain RMI Architecture?
  
• How do you communicate in between Applets & Servlets ?
  
• What is the use of Servlets ?
  
• What is JDBC? How do you connect to the Database ?
  
• In an HTML form I have a Button which makes us to open another page in 15 seconds. How will do you that ?
  
• What is the difference between Process and Threads ?
  
• What is the difference between RMI & Corba ?
  
• What are the services in RMI ?
  
• How will you initialize an Applet ?
  
• What is the order of method invocation in an Applet ?
  
• When is update method called ?
  
• How will you pass values from HTML page to the Servlet ?
  
• Have you ever used HashTable and Dictionary ?
  
• How will you communicate between two Applets ?
  
• What are statements in JAVA ?
  
• What is JAR file ?
  
• What is JNI ?
  
• What is the base class for all swing components ?
  
• What is JFC ?
  
• What is Difference between AWT and Swing ?
  
• Considering notepad/IE or any other thing as process, What will happen if you start notepad or IE 3 times? Where 3 processes are started or 3 threads are started ?
  
• How does thread synchronization occurs inside a monitor ?
  
• How will you call an Applet using a Java Script function ?
  
• Is there any tag in HTML to upload and download files ?
  
• Why do you Canvas ?
  
• How can you push data from an Applet to Servlet ?
  
• What are 4 drivers available in JDBC ?
  
• How you can know about drivers and database information ?
  
• If you are truncated using JDBC, How can you know ..that how much data is truncated ?
  
• And What situation , each of the 4 drivers used ?
  
• How will you perform transaction using JDBC ?
  
• In RMI, server object first loaded into the memory and then the stub reference is sent to the client ? or whether a stub reference is directly sent to the client ?
  
• Suppose server object is not loaded into the memory, and the client request for it , what will happen?
  
• What is serialization ?
  
• Can you load the server object dynamically? If so, what are the major 3 steps involved in it ?
  
• What is difference RMI registry and OSAgent ?
  
• To a server method, the client wants to send a value 20, with this value exceeds to 20,. a message should be sent to the client ? What will you do for achieving for this ?
  
• What are the benefits of Swing over AWT ?
  
• Where the CardLayout is used ?
  
• What is the Layout for ToolBar ?
  
• What is the difference between Grid and GridbagLayout ?
  
• How will you add panel to a Frame ?
  
• What is the corresponding Layout for Card in Swing ?
  
• What is light weight component ?
  
• Can you run the product development on all operating systems ?
  
• What is the webserver used for running the Servlets ?
  
• What is Servlet API used for connecting database ?
  
• What is bean ? Where it can be used ?
  
• What is difference in between Java Class and Bean ?
  
• Can we send object using Sockets ?
  
• What is the RMI and Socket ?
  
• How to communicate 2 threads each other ?
  
• What are the files generated after using IDL to Java Compilet ?