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  • Explian Autoboxing and unboxing conversions in Java
    Core Java

    Posted By: vijay

  • Why String is immutable in Java?
    Core Java

    Posted By: Smith

  • Explain the difference between a process and a thread?
    Core Java

    Posted By: Wilber

  • How to sort a List of Java Bean in Ascending Order?
    Core Java

    Posted By: CarlosBivatte

  • What are the difference between Java arrays and Collections?
    Core Java

    Posted By: Anonymous

  • How to sort a collection in Java?
    Core Java

    Posted By: Roland

  • What are wrapper classes?
    Core Java

    Posted By: JesseThick

  • List few differences between Array list and vector in Java?
    Core Java

    Posted By: Quincy

  • Why main() method of Java program must be static?
    Core Java

    Posted By: Ella

  • What are access modifiers in java?
    Core Java

    Posted By: Bruce

  • How to create immutable class in java?
    Core Java

    Posted By: Gerhard

  • Give me a real time example of Abstraction?
    Core Java

    Posted By: Caleb

  • What is the Dictionary class?
    Core Java

    Posted By: Guss

  • Can you create an instance of interface?
    Core Java

    Posted By: Wood

  • What is implicit casting in Java?
    Core Java

    Posted By: Ervin

  • What is JIT ?
    Core Java

    Posted By: Allen

  • What are Checked and Unchecked exceptions in Java?
    Core Java

    Posted By: Sheldon

  • What is default access modifier of an Interface in Java?
    Core Java

    Posted By: Fifium App Development

  • Why to use Iterator in Java? Is it is an Interface or Class?
    Core Java

    Posted By: Glen

  • What is garbage collector in java?
    Core Java

    Posted By: Curley

  • What is use of transient keyword in Java?
    Core Java

    Posted By: kato

  • How to suspend a thread?
    Core Java

    Posted By: Carson

  • What is deadlock? How can you prevent it, avoid it?
    Core Java

    Posted By: Adolf

  • What is a NullPointerException?
    Core Java

    Posted By: Jasper

  • What is the difference between Iterator and Enumeration in Java?
    Core Java

    Posted By: Ora

  • In how many ways a thread can be created in Java?
    Core Java

    Posted By: Brooks

  • Explain Stream Tokenizer in Java?
    Core Java

    Posted By: Baldwin

  • How to convert a string to long in Java?
    Core Java

    Posted By: uqtifanano

  • How to add and remove nodes in Jtree?
    Core Java

    Posted By: Hans

  • How do I break out of nested loops in Java?
    Core Java

    Posted By: Cas

  • How to calculate difference between two dates in Java?
    Core Java

    Posted By: Cyril

  • What is Double Brace initialization in Java?
    Core Java

    Posted By: Chauncey

  • Why do we need constructor in Java?
    Core Java

    Posted By: Michel

  • Explain the difference between ArrayList and Vector?
    Core Java

    Posted By: Valentine

  • Is there any difference between a = a + b and a += b expressions in Java?
    Core Java

    Posted By: Newton

  • What are raw types in Java?
    Core Java

    Posted By: Milton

  • How to check if a file exists or not in Java?
    Core Java

    Posted By: GORU RAVi

  • How to print nodes of a Binary tree in Java?
    Core Java

    Posted By: Arther

  • What are Inner classes in Java?
    Core Java

    Posted By: Dipali Sharma

  • Is 'sizeof' is a keyword or method in Java?
    Core Java

    Posted By: Joseph

  • Explain What is Connection Pooling?
    Core Java

    Posted By: Wylie

  • What is the default initialized value of a String in Java.
    Core Java

    Posted By: Father

  • What is Static binding ?
    Core Java

    Posted By: Rodney

  • Difference between sleep and suspend ?
    Core Java

    Posted By: MichaeltoX

  • What is JAR file?
    Core Java

    Posted By: Jonathan

  • What is super in Java?
    Core Java

    Posted By: Ethan

  • What is classloader in Java?
    Core Java

    Posted By: Clay

  • What is difference between final, finally and finalize?
    Core Java

    Posted By: Sterling

  • What is Externalizable?
    Core Java

    Posted By: Wilfred

  • What is the difference between JVM and JRE?
    Core Java

    Posted By: Bennett

  • How to interrupt a thread explicitly ?
    Core Java

    Posted By: Willie

  • What is difference between core Java and Java EE?
    Core Java

    Posted By: Dan

  • What is runnable?
    Core Java

    Posted By: Charlie Pan

  • What is the difference between a StringBuffer and String in Java?
    Core Java

    Posted By: Bert

  • Describe the differences between C++ and Java.
    Core Java

    Posted By: Ambers

  • What is difference between Abstract and final?
    Core Java

    Posted By: akshay anand

  • Why java doesn't support multiple inheritance?
    Core Java

    Posted By: Obed

  • How would you design a garbage collector?
    Core Java

    Posted By: Rajat

  • Does Java support pointer variables?
    Core Java

    Posted By: AnHo

  • How to implement multithreading in Java?
    Core Java

    Posted By: Robertrof

  • What is difference between JVM and JRE?
    Core Java

    Posted By: Alvah

  • What is difference between call by value and call by reference?
    Core Java

    Posted By: Charlie

  • Explain final, finally, finalize difference
    Core Java

    Posted By: Raymond

  • What is the difference between JDK and JVM?
    Core Java

    Posted By: Guadalupe

  • What is overloading and overriding in java?
    Core Java

    Posted By: Daisy

  • What is Enum in Java?
    Core Java

    Posted By: kato

  • What is instanceof keyword?
    Core Java

    Posted By: Burl

  • What is the final method?
    Core Java

    Posted By: Anonymous

  • What is JAVA_HOME environment variable?
    Core Java

    Posted By: rachelparadis

  • What is the difference between notify and notify All methods ?
    Core Java

    Posted By: Ray

  • What is an Iterator interface?
    Core Java

    Posted By: Emit

  • What are null or Marker interfaces in Java?
    Core Java

    Posted By: Sterling

  • What is Jagged Arrays in java?
    Core Java

    Posted By: Blas

  • What is the purpose of the Runtime class?
    Core Java

    Posted By: Jay

  • Can we cast double to a bytein Java?
    Core Java

    Posted By: Hermann

  • What is the advantage of thread yielding?
    Core Java

    Posted By: Frank

  • What is the Collections API?
    Core Java

    Posted By: addanki

  • What is the Vector class?
    Core Java

    Posted By: Oswald

  • What are Anonymous Classes?
    Core Java

    Posted By: Stacy

  • What is preemptive scheduling?
    Core Java

    Posted By: Thaddeus

  • What is the difference between JDK, JRE, and JVM?
    Core Java

    Posted By: Sharad Jaiswal

  • How many types of memory areas are allocated by JVM?
    Core Java

    Posted By: Sharad Jaiswal

  • What is JIT ( Just-In-Time) compiler?
    Core Java

    Posted By: Sharad Jaiswal

  • What is ‘write once and run anywhere’ in JAVA?
    Core Java

    Posted By: Sharad Jaiswal

  • If I don’t provide any arguments on the command line, then the String array of Main method will be empty or null?
    Core Java

    Posted By: Sharad Jaiswal

  • What is the default value of the local variables?
    Core Java

    Posted By: Sharad Jaiswal

  • What will be the initial value of an object reference which is defined as an instance variable?
    Core Java

    Posted By: Sharad Jaiswal

  • What is a constructor?
    Core Java

    Posted By: Sharad Jaiswal

  • What are Rules to define a constructor?
    Core Java

    Posted By: Sharad Jaiswal

  • What is the purpose of default constructor?
    Core Java

    Posted By: Sharad Jaiswal

  • Is constructor inherited?
    Core Java

    Posted By: Sharad Jaiswal

  • Can you make a constructor final?
    Core Java

    Posted By: Sharad Jaiswal

  • What is static variable?
    Core Java

    Posted By: Sharad Jaiswal

  • What is the static method?
    Core Java

    Posted By: Sharad Jaiswal

  • What is static block?
    Core Java

    Posted By: Sharad Jaiswal

  • Can we execute a program without a main() method?
    Core Java

    Posted By: Sharad Jaiswal

  • What is the difference between static (class) method and instance method?
    Core Java

    Posted By: Sharad Jaiswal

  • What is method overloading?
    Core Java

    Posted By: Sharad Jaiswal

  • What is “this” in java?
    Core Java

    Posted By: Sharad Jaiswal

  • What is Inheritance?
    Core Java

    Posted By: Sharad Jaiswal

  • Why is multiple inheritances not supported in java?
    Core Java

    Posted By: Sharad Jaiswal

  • What is composition?
    Core Java

    Posted By: Sharad Jaiswal

  • What is object cloning?
    Core Java

    Posted By: Sharad Jaiswal

  • Can we override static method?
    Core Java

    Posted By: Sharad Jaiswal

  • What is the difference between method Overloading and Overriding?
    Core Java

    Posted By: Sharad Jaiswal

  • What is Exception Handling?
    Core Java

    Posted By: Sharad Jaiswal

  • What is final variable, final class, final method?
    Core Java

    Posted By: Sharad Jaiswal

  • What is Polymorphism?
    Core Java

    Posted By: Sharad Jaiswal

  • What is Runtime Polymorphism?
    Core Java

    Posted By: Sharad Jaiswal

  • What is dynamic binding?
    Core Java

    Posted By: Sharad Jaiswal

  • What is Abstraction?
    Core Java

    Posted By: Sharad Jaiswal

  • What is the difference between abstraction and encapsulation?
    Core Java

    Posted By: Sharad Jaiswal

  • What is the difference between Checked Exception and Unchecked Exception?
    Core Java

    Posted By: Sharad Jaiswal

  • What is exception propagation?
    Core Java

    Posted By: Sharad Jaiswal

  • What is nested class?
    Core Java

    Posted By: Sharad Jaiswal

  • What is the purpose of the toString() method in java?
    Core Java

    Posted By: Sharad Jaiswal

  • What is Garbage Collection?
    Core Java

    Posted By: Sharad Jaiswal

  • What is the purpose of finalize() method?
    Core Java

    Posted By: Sharad Jaiswal

  • What is the difference between final, finally and finalize?
    Core Java

    Posted By: Sharad Jaiswal

  • What is a Stream?
    Core Java

    Posted By: Sharad Jaiswal

  • What is serialization?
    Core Java

    Posted By: Sharad Jaiswal

  • What is Socket Class?
    Core Java

    Posted By: Sharad Jaiswal

  • What is a thread?
    Core Java

    Posted By: Sharad Jaiswal

  • What is Collection? What is a Collection Framework?
    Core Java

    Posted By: Sharad Jaiswal

  • What is Pass by Value and Pass by Reference?
    Core Java

    Posted By: Sharad Jaiswal

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