java 英语面试题(各外企java英文面试题汇总-100问)
Question:What is the difference between an Interface and an Abstract class?
Question: What is the purpose of garbage collection in Java, and when is it used?
Question:  Describe synchronization in respect to multithreading.
Question:  Explain different way of using thread?
Question:  What are pass by reference and passby value?
Question:  What is HashMap and Map?
Question:  Difference between HashMap and HashTable?
Question: Difference between Vector and ArrayList?
Question:  Difference between Swing and Awt?
Question:  What is the difference between a constructor and a method?
Question:  What is an Iterator?
Question:  State the significance of public, private, protected, default modifiers both singly and in combination and state the effect of package relationships on declared items qualified by these modifiers.
Question: What is an abstract class?
Question: What is static in java?
Question:What is final?
Question: What if the main method is declared as private?
Question: What if the static modifier is removed from the signature of the main method?
Question: What if I write static public void instead of public static void?
Question: What if I do not provide the String array as the argument to the method?
Question: What is the first argument of the String array in main method?
Question: If I do not provide any arguments on the command line, then the String array of Main method will be empty or null?
Question: How can one prove that the array is not null but empty using one line of code?
Question: What environment variables do I need to set on my machine in order to be able to run Java programs?
Question: Can an application have multiple classes having main method?
java面试八股文Question: Can I have multiple main methods in the same class?
Question: Do I need to import java.lang package any time? Why ?
Question: Can I import same package/class twice? Will the JVM load the package twice at runtime?
Question: What are Checked and UnChecked Exception?
Question: What is Overriding?
Question: What are different types of inner classes?
Question: Are the imports checked for validity at compile time? e.g. will the code containing an import such as java.lang.ABCD compile?
Question: Does importing a package imports the subpackages as well? e.g. Does importing com.MyTest.* also import com.MyTest.UnitTests.*?
Question: What is the difference between declaring a variable and defining a variable?
Question: What is the default value of an object reference declared as an instance variable?
Question: Can a top level class be private or protected?
Question: What type of parameter passing does Java support?
Question: Primitive data types are passed by reference or pass by value?
Question: Objects are passed by value or by reference?
Question: What is serialization?
Question: How do I serialize an object to a file?
Question: Which methods of Serializable interface should I implement?
Question: How can I customize the seralization process? i.e. how can one have a control over the serialization process?
Question: What is the common usage of serialization?
Question: What is Externalizable interface?
Question: When you serialize an object, what happens to the object references included in the object?
Question: What one should take care of while serializing the object?
Question: What happens to the static fields of a class during serialization?
Question: Does Java provide any construct to find out the size of an object?
Question: Give a simplest way to find out the time a method takes for execution without using any profiling tool?
Question: What are wrapper classes?
Question: Why do we need wrapper classes?
Question: What are checked exceptions?
Question: What are runtime exceptions?
Question: What is the difference between error and an exception??
Question: How to create custom exceptions?
Question: If I want an object of my class to be thrown as an exception object, what should I do?
Question: If my class already extends from some other class what should I do if I want an instance of my class to be thrown as an exception object?
Question: How does an exception permeate through the code?
Question: What are the different ways to handle exceptions?
Question: What is the basic difference between the 2 approaches to 1> try catch block and 2> specifying the candidate exceptions in the throws clause?
When should you use which approach?
Question: Is it necessary that each try block must be followed by a catch block?
Question: If I write return at the end of the try block, will the finally block still execute?
Question: If I it (0); at the end of the try block, will the finally block still execute?
Question: How are Observer and Observable used?
Question: What is synchronization and why is it important?
Question: How does Java handle integer overflows and underflows?
Question: Does garbage collection guarantee that a program will not run out of memory?
Question: What is the difference between preemptive scheduling and time slicing?  Question: When a thread is created and started, what is its initial state?  Question: What is the purpose of finalization?
Question: What is the Locale class?
Question: What is the difference between a while statement and a do statement?  Question: What is the difference between static and non-static variables?  Question: How are this() and super() used with constructors?
Question: What are synchronized methods and synchronized statements?
Question: What is daemon thread and which method is used to create the daemon thread?  Question: Can applets communicate with each other?
Question: What are the steps in the JDBC connection?
Question: How does a try statement determine which catch clause should be used to handle an exception?
Question: Is Empty .java file a valid source file?
Question: Can a .java file contain more than one java classes?
Question: Is String a primitive data type in Java?
Question: Is main a keyword in Java?
Question: Is next a keyword in Java?
Question: Is delete a keyword in Java?
Question: Is exit a keyword in Java?
Question: What happens if you dont initialize an instance variable of any of the primitive types in Java?
Question: What will be the initial value of an object reference which is defined as an instance variable?
Question: What are the different scopes for Java variables?
Question: What is the default value of the local variables?
Question: How many objects are created in the following piece of code?
MyClass c1, c2, c3;
c1 = new MyClass ();
c3 = new MyClass ();
Question: Can a public class MyClass be defined in a source file named YourClass.java?
Question: Can main method be declared final?
Question: What will be the output of the following statement?
System.out.println ("1" + 3);
Question: What will be the default values of all the elements of an array defined as an instance variable?
Question: Can an unreachable object become reachable again?
Question: What method must be implemented by all threads?
Question: What are synchronized methods and synchronized statements?
Question: What is Externalizable?
Question: What modifiers are allowed for methods in an Interface?