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Ans. Suspend method is used to suspend thread which can be restarted by using resume() method. stop() is used to stop the thread, it cannot be restarted again.
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LikeDiscussCorrect / Improve  java   threads   multi threading   operating system   synchronization   suspend   stop basic  rare
Q582. What is the difference between System.console.write and System.out.println ?
Ans. System.console() returns null if your application is not run in a terminal (though you can handle this in your application)System.console() provides methods for reading password without echoing charactersSystem.out and System.err use the default platform encoding, while the Console class output methods use the console encoding
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Q583. Tell something about BufferedWriter ? What are flush() and close() used for ?
Ans. BufferedWriter is temporary source for data storage.BufferedWriter is used to write character data to the file.Flush() is method available in B.W which ensures that all data items are written to file including last character.Close() is used to closes the character output stream.
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Ans. Scanner class introduced in Java 1.5 for reading Data Stream from the imput device. Previously we used to write code to read a input using DataInputStream. After reading the stream , we can convert into respective data type using in.next() as String ,in.nextInt() as integer, in.nextDouble() as Double etc
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Ans. When a task invokes yield(), it changes from running state to runnable state. When a task invokes sleep(), it changes from running state to waiting/sleeping state.
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LikeDiscussCorrect / Improve  java   threads   multi threading   scheduling   thread states   yield   sleeping
Usually asked only to fresh graduates and less experienced developers.
Q587. What is a daemon thread? Give an Example ?
Ans. These are threads that normally run at a low priority and provide a basic service to a program or programs when activity on a machine is reduced. garbage collector thread is daemon thread.
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What kind of thread is Garbage collection thread ?
Daemon Thread
User Thread
System Thread
Active Thread
Which of following is Daemon Thread ?
Thread Scheduler
Daemon Thread
Both of above
None of above
Q588. What is the difference between AWT and Swing?
Ans. Swing provides both additional components like JTable, JTree etc and added functionality to AWT-replacement components.
Swing components can change their appearance based on the current “look and feel†library that’s being used.
Swing components follow the MVC paradigm, and thus can provide a much more flexible UI.
Swing provides extras for components, such as icons on many components, decorative borders for components, tool tips for components etc.
Swing components are lightweight than AWT.
Swing provides built-in double buffering ,which means an off-screen buffer is used during drawing and then the resulting bits are copied onto the screen.
Swing provides paint debugging support for when you build your own component.
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LikeDiscussCorrect / Improve  java   awt   java ui   swing   difference between swing and awt   architecture
Q589. What is the order of method invocation in an applet?
Ans. public void init() public void start() public void stop() public void destroy()
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Ans. LDAP servers are typically used in J2EE applications to authenticate and authorise users. LDAP servers are hierarchical and are optimized for read access, so likely to be faster than database in providing read access.
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LikeDiscussCorrect / Improve  java   j2ee   ldap   servers   authentication   authorization   architecture   technical lead   technical architect  production support Asked in 1 Companies
Ans. Spring configuration file is an XML file. This file contains the classes information and describes how these classes are configured and introduced to each other.
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Ans. The Spring container is able to autowire relationships between collaborating beans. This means that it is possible to automatically let Spring resolve collaborators (other beans) for your bean by inspecting the contents of the BeanFactory without using and elements.
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Ans. Translation of JSP PageCompilation of JSP PageClassloading (class file is loaded by the classloader)Instantiation (Object of the Generated Servlet is created).Initialization ( jspInit() method is invoked by the container).Reqeust processing ( _jspService() method is invoked by the container).Destroy ( jspDestroy() method is invoked by the container).
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Ans. In GUI programming, an object that can be registered to be notified when events of some given type occur. The object is said to listener? for the events.
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Ans. A way of encoding characters as binary numbers. The Unicode character set includes characters used in many languages, not just English. Unicode is the character set that is used internally by Java.
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Ans. ThreadFactory is an interface that is meant for creating threads instead of explicitly creating threads by calling new Thread(). Its an object that creates new threads on demand. Using thread factories removes hardwiring of calls to new Thread, enabling applications to use special thread subclasses, priorities, etc.
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Ans. You can put related classes together as a single logical group.
Nested classes can access all class members of the enclosing class, which might be useful in certain cases.
Nested classes are sometimes useful for specific purposes. For example, anonymous inner classes are useful for writing simpler event-handling code with AWT/Swing.
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Ans. The accessibility (public, protected, etc.) of the static nested class is defined by the outer class.
A static nested class is not an inner class, it's a top-level nested class.
The name of the static nested class is expressed with OuterClassName.NestedClassName syntax.
When you define an inner nested class (or interface) inside an interface, the nested class is declared implicitly public and static.
Static nested classes can be declared abstract or final.
Static nested classes can extend another class or it can be used as a base class.
Static nested classes can have static members.
Static nested classes can access the members of the outer class (only static members, obviously).
The outer class can also access the members (even private members) of the nested class through an object of nested class. If you don't declare an instance of the nested class, the outer class cannot access nested class elements directly.
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Ans. The accessibility (public, protected, etc.) of the inner class is defined by the outer class.
Just like top-level classes, an inner class can extend a class or can implement interfaces.
Similarly, an inner class can be extended by other classes, and an inner interface can be implemented or extended by other classes or interfaces.
An inner class can be declared final or abstract.Inner classes can have inner classes, but you will have a hard time reading or understanding such complex nesting of classes.
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Ans. You can create a non-static local class inside a body of code. Interfaces cannot have local classes, and you cannot create local interfaces.
Local classes are accessible only from the body of the code in which the class is defined. The local classes are completely inaccessible outside the body of the code in which the class is defined.
You can extend a class or implement interfaces while defining a local class.
A local class can access all the variables available in the body of the code in which it is defined. You can pass only final variables to a local inner class.
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Q608. What will happen if class implement two interface having common method?
Ans. That would not be a problem as both are specifying the contract that implement class has to follow. If class C implement interface A & interface B then Class C thing I need to implement print() because of interface A then again Class think I need to implement print() again because of interface B, it sees that there is already a method called test() implemented so it's satisfied.
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Q609. What is the advantage of using arrays over variables ?
Ans. Arrays provide a structure wherein multiple values can be accessed using single reference and index. This helps in iterating over the values using loops.
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Q610. Difference between Class#getInstance() and new operator ?
Ans. Class.getInstance doesn't call the constructor whereas if we create an object using new operator , we need to have a matching constructor or copiler should provide a default constructor.
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