JAVA CONCEPTS

Important Java Mcq 1

Which of the following has a method named flush?

a. Output stream

b. Input stream

c. Reader stream

d. Input reader stream

Answer:

a. Output stream

Explanation:

flush() of output stream class is used to flush the content of the buffer to the Output stream. For example, when we write data to a stream, it is not written immediately, it is buffered. So use flush() when you need to be sure that all your data from the buffer is written.

Java uses threads to allow following type of environment

a) Symmetric b) Asymmetric c) Synchronous d) Asynchronous Answer: d) Asynchronous

You read the following statement in a Java program that compiles and executes submarine.dive(depth); What can you say for sure?

a. Depth must be an int. b. Dive must be a method. c. Dive must be the name of an instance field. d. Submarine must

Which are the examples of an application server?

a. Apache b. JBoss c. WebLogic d. Both c and b. Answer: d. Both c and b. Explanation JBoss and WebLogic are examples of application

Which of the following cannot be used as identifiers in java?

a. variable names b. class names c. key words d. objects Answer: c. key words Explanation: We cannot use keywords like int, float , etc