JAVA Multiple Choice Questions :-
1. Java programs are
A) Faster than others
B) Platform independent
C) Not reusable
D) Not scalable
2. Java has its origin in
A) C programming language
B) PERRL
C) COBOL
D) Oak programming language
3. Which one of the following is true for Java
A) Java is object oriented and interpreted
B) Java is efficient and faster than C
C) Java is the choice of everyone.
D) Java is not robust.
4. The command javac is used to
A) debug a java program
B) compile a java program
C) interpret a java program
D) execute a java program
5. Java servlets are an efficient and powerful solution for creating ………….. for the web.
A) Dynamic content
B) Static content
C) Hardware
D) Both a and b
6. Filters were officially introduced in the Servlet ……………… specification.
A) 2.1
B) 2.3
C) 2.2
D) 2.4
7. Which is the root class of all AWT events
A) java.awt.ActionEvent
B) java.awt.AWTEvent
C) java.awt.event.AWTEvent
D) java.awt.event.Event
8. OOP features are
i) Increasing productivity ii) Reusability
iii) Decreasing maintenance cost iv) High vulnerability
A) 1,2 & 4
B) 1,2 & 3
C) 1, 2 & 4
D) none of the above
9. break statement is used to
i) get out of method ii) end aprogram
iii) get out of a loop iv) get out of the system
A) 1 & 2
B) 1,2 & 3
C) 1 & 3
D) 3
10. Native – protocol pure Java converts ……….. into the ………… used by DBMSs directly.
A) JDBC calls, network protocol
B) ODBC class, network protocol
C) ODBC class, user call
D) JDBC calls, user call
11. The JDBC-ODBC bridge allows ……….. to be used as ………..
A) JDBC drivers, ODBC drivers
B) Drivers, Application
C) ODBC drivers, JDBC drivers
D) Application, drivers
12. Which of the following is true about Java.
A) Java does not support overloading.
B) Java has replaced the destructor function of C++
C) There are no header files in Java.
D) All of the above.
13. ……………. are not machine instructions and therefore, Java interpreter generates machine code that can be directly executed by the machine that is running the Java program.
A) Compiled Instructions
B) Compiled code
C) byte code
D) Java mid code
14. The command javac
A) Converts a java program into binary code
B) Converts a java program into bytecode
C) Converts a java program into machine language
D) None of the above.
15. Which of the following is not the java primitive type
A) Byte
B) Float
C) Character
D) Long double
16. Command to execute compiled java program is
A) java
B) javac
C) run
D) javaw
17. Java Servlet
i) is key component of server side java development
ii) is a small pluggable extension to a server that enhances functionality
iii) runs only in Windows Operating System
iv) allows developers to customize any java enabled server
A) i, ii & iii are ture
B) i, iii & iv are true
C) ii, iii & iv are true
D) i, ii & iv are true
18. Inner classes are
A) anonymous classes
B) nested classes
C) sub classes
D) derived classes
19. How many times does the following code segment execute
int x=1, y=10, z=1;
do{y–; x++; y-=2; y=z; z++} while (y>1 && z<10);
A) 1
B) 10
C) 5
D) infinite
20. State weather the following statement is true or false for EJB.
1. EJB exists in the middle-tier
2. EJB specifies an execution environment
3. EJB supports transaction processing
A) 1-true, 2. true, 3. true
B) 1- true, 2. false, 3. true
C) 1- false, 2- false, 3- false
D) 1-true, 2-true, 3-false
21. All java classes are derived from
A) java.lang.Class
B) java.util.Name
C) java.lang.Object
D) java.awt.Window
22. The jdb is used to
A) Create a jar archive
B) Debug a java program
C) Create C header file
D) Generate java documentation
23. What would happen if “String[]args” is not included as argument in the main method.
A) No error
B) Compilation error
C) Program won’t run
D) Program exit
24. For execution of DELETE SQL query in JDBC, …………. method must be used.
A) executeQuery()
B) executeDeleteQuery()
C) executeUpdate()
D) executeDelete()
25. Which method will a web browser call on a new applet?
A) main method
B) destroy method
C) execute method
D) init method
26. Which of the following is not mandatory in variable declaration?
A) a semicolon
B) an identifier
C) an assignment
D) a data type
27. When a program class implements an interface, it must provide behavior for
A) two methods defined in that interface
B) any methods in a class
C) only certain methods in that interface
D) all methods defined in that interface
28. In order to run JSP ……………….. is required.
A) Mail Server
B) Applet viewer
C) Java Web Server
D) Database connection
29. State true of false.
i) AWT is an extended version of swing
ii) Paint( ) of Applet class cannot be overridden
A) i-false, ii-false
B) i-false,ii-true
C) i-true, ii-false
D) i-true, ii-true
30. Prepared Statement object in JDBC used to execute……….. queries.
A) Executable
B) Simple
C) High level
D) Parameterized
31. In Java variables, if first increment of the variable takes place and then the assignment occurs. This operation is also called ……………………….. .
A) pre increment
B) post increment
C) incrementation
D) pre incrementation
32. When the operators are having the same priority, they are evaluated from …………….. …………. in the order they appear in the expression.
A) right to left
B) left to right
C) any of the order
D) depends on compiler
33. In java, …………. can only test for equality, where as ………… can evaluate any type of the Boolean expression.
A) switch, if
B) if, switch
C) if, break
D) continue, if
34. The ………………….. looks only for a match between the value of the expression and one of its case constants.
A) if
B) match
C) switch
D) None of the above
35. System.in.read() is being used, the program must specify the ……………… clause.
A) throws.java.out.IOException
B) throws.java.in.IOException
C) throws.java.io.IOException
D) throws.java.io.InException
36. By using ………………. you can force immediate termination of a loop, by passing the conditional expression and any remaining code in the body of the loop.
A) Break
B) Continue
C) Terminate
D) Loop Close
37. The out object is an object encapsulated inside the …………….. class, and represents the standard output device.
A) standard
B) local
C) globlal
D) system
38. The third type of comment is used by a tool called ……………… for automatic generation of documentation.
A) Java commenting
B) Java generator
C) Java doc
D) Java loc
39. In the second type the information written in java after // is ignored by the …………………..
A) Interpreter
B) Compiler
C) Programmer
D) All of the above
40. The compiled java program can run on any ………………… plateform having Java Virtual Machine (JVM) installed on it.
A) program
B) java
C) hardware
D) non java
41. Preparedstatement Object in JDBC is used to execute ……………………… queries.
A) executable
B) simple
C) high level
D) parameterized
42. In JDBC …………………… imports all Java classes concerned with database connectivity.
A) javax.sql.*
B) java.mysql.*
C) java.sql.*
D) com.*
43. MS-SQL stores data in a …………………… file format.
A) .DAT
B) .MDB
C) .MSSQL
D) .OBJ
44. Ingres is a ……………………
A) Socket
B) Compiler
C) Database
D) Web server
45. In Java servlet method init( ) is called ………………… times.
A) 1
B) 2
C) 0
D) multiple
46. State true or false for Java Program.
i) All class variables are instance variables
ii) All protected methods are friendly methods
A) i-false, ii-false
B) i-false, ii-true
C) i-true, ii-false
D) i-true, ii-true
47. State true or false for Java Program.
i) Data members of an interface are by default final
ii) An abstract class has implementations of all methods defined inside it.
A) i-false, ii-false
B) i-false, ii-true
C) i-true, ii-false
D) i-true, ii-true
48. …………………… of a remotely accessible object must implement …………….
A) all methods, RemoteException
B) class, RemoteException
C) class, RemoteInterface
D) all methods, RemoteInterface
49. ………………….is the key to ……………………
A) Serialization, persistence
B) Persistence, inheritance
C) Inheritance, object
D) Persistence, serialization
50. A method name myMethod( ) that needs two integer arguments is declared as
A) public void myMethod( );
B) public void myMethod(int a, int b);
C) public void myMethod(int a, b);
D) public int myMethod(a, b);
51. JSP embeds in ……………. in ………………….
A) Servlet, HTML
B) HTML, Java
C) HTML, Servlet
D) Java, HTML
52. The class at the top of exception class hierarchy is ……………………..
A) ArithmeticException
B) Throwable
C) Class
D) Exception
53. In a java program, package declaration ……………….. import statements.
A) must precede
B) must succeed
C) may precede or succeed
D) none
54. The class string belongs to ………………. package.
A) java.awt
B) java.lang
C) java.applet
D) java.string
55. …………… package is used by compiler itself. So it does not need to be imported for use.
A) java.math
B) java.awt
C) java.applet
D) java.lang
56. State true or false for the following statements in Java.
i) Java beans slow down software development process.
ii) Java Servlets do not have built in multithreading feature.
A) i-false, ii-false
B) i-false, ii-true
C) i-true, ii-false
D) i-true, ii-true
57. State whether true or false.
i) init( ) of servlet is called after a client request comes in
ii) Servlets are ultimately converted into JSP
A) i-false, ii-false
B) i-false, ii-true
C) i-true, ii-false
D) i-true, ii-true
58. What will be the result of compiling following code.
public class MyClass{
public static void main(String args[]){
System.out.println(“In first main()”);
}
public static void main(char args[]){
System.out.println(‘a’);
}
}
A) Code will not compile and will give “Duplicate main() method declaration” error
B) Code will compile correctly but will give a runtime exception
C) Code will compile correctly and will print “In first main()” (without quotes) when it is run
D) Code will compile correctly and will print “a” (without quotes) when it is run
59.Match the following.
a) Java 1) is a tool for debugging java program
b) Javah 2) is a tool for creating C-like header files
c) Javap 3) runs java bytecode
d) jdb 4) prints java code representation
A) a-3, b-2,c-1
B) a-3, b-2, c-4, d-1
C) a-1, b-2, c-3, d-4
D) a-2, b-1, c-3, d-4
60.State true or false.
i) init() is called after start() in applet
ii) applets are used for networking
iii) inheritance is a part of Java Foundation Classes
iv) final does not prevent inheritance
A) i-true, ii-true, iii-false, iv-true
B) i-false, ii-false, iii-false, iv-false
C) i-true, ii-true, iii-true, iv-true
D) i-true, ii-false, iii-false, iv-false
61. The ……………… and ……………….. classes are abstract classes that support reading and writing of byte streams.
A) reader, writer
B) inputstream, outputstream
C) objectinputstream, objectoutputstream
D) none
62. What is the error in the following code?
class Test
{
abstract void display( );
}
A) No error
B) Method display( ) should be declared as static
C) Test class should be declared as abstract
D) Test class should be declared as public
63. A package is a collection of
A) classes
B) interfaces
C) editing tools
D) classes and interfaces
64. Which of the following methods belong to the string class?
A) length( )
B) compare To ( )
C) equals ( )
D) All of them
65. What will be the output of the following code?
byte x=64, y;
y= (byte) (x<<2);
System.out.println(y);
A) 0
B) 1
C) 2
D) 64
66. If m and n are int type variables, what will be the result of the expression
m%n
when m=5 and n=2 ?
A) 0
B) 1
C) 2
D) None of the above
67. Which of the following control expressions are valid for an if statement?
A) An integer expression
B) A Boolean expression
C) Either A or B
D) Neither A nor B
68. The concept of multiple inheritance is implemented in Java by
A) extending two or more classes
B) extending one class and implementing one or more interfaces
C) implementing two or more interfaces
D) both B and C
69. Which of the following do not represent legal flow control statements?
A) break;
B) return;
C) exit();
D) continue outer;
70. Data input is
A) an abstract class defined in java.io
B) a class we can use to read primitive data types
C) an interface that defines methods to open files.
D) an interface that defines methods to read primitive data types.
71. Using which keyword we can access value of the instance variables and class variables of that class inside the method of that class itself.
A) super
B) final
C) this
D) either super or this
72. If a variable is declared final, it must include …………………. value.
A) integer
B) no
C) initial
D) float
73. State true or false.
i) Jpanel is a class included in awt package.
ii) Anonymous classes are mostly used for event handling.
iii) Names of anonymous classes must be unique
iv) JOptionPane is an inner class
A) i-false, ii-false, iii-true, iv-true
B) i-true, ii-false, iii-true, iv-false
C) i-false, ii-true, iii-false, iv-false
D) i-true, ii-false, iii-false, iv-true
74. In java, string is a ………….
A) primitive data type
B) abstract data type
C) combination of boolean
D) None of the above
75. Methods can be overloaded with a difference only in the type of the return value ..
A) Not supported
B) False
C) True
D) None of the above
76. Each method in a java class must have a unique name .
A) Not necessary
B) True
C) False
D) None of the above
77. State true or false.
i) comparisons precede logical operations in java
ii) assignment operations succeed increment operations
iii) arithmetic operations succeed comparisons
iv) x precede +
A) i-true, ii-true, iii-false, iv-true
B) i-true, ii-false, iii-true, iv-false
C) i-false, ii-true, iii-false, iv-false
D) i-true, ii-false, iii-false, iv-true
78. It is important feature of java that it always provides a default constructor to a class.
A) Not supported
B) False
C) True
D) None of the above
79. ………………….. is the key to ………………
A) Serialization, persistence
B) Persistence, inheritance
C) Inheritance, object
D) Persistence, serialization
80. State true of false.
i) Public can only be assigned to class
ii) Protected protects a statement
iii) Protected method is never accessible outside the package
iv) Friendly variable may be accessible outside class
A) i-true, ii-true, iii-false, iv-true
B) i-true, ii-false, iii-true, iv-false
C) i-false, ii-true, iii-false, iv-false
D) i-true, ii-false, iii-false, iv-true
81. In java a ………………….. is a sequence of characters.
Java Objective Questions with Answers
Schema of the general architecture of a program running in a Java Virtual Machine (Photo credit: Wikipedia)
A) string
B) arrayChar
C) groupChar
D) collection
82. Java programs perform I/O through ………..
A) I/O methods
B) I/O package
C) streams
D) compiler
83. What is byte code in the context of Java?
A) The type of code generated by a Java compiler
B) The type of code generated by a Java Virtual Machine
C) It is another name for Java source file
D) It is the code written within the instance methods of a class
84. Which of the following statements about abstract methods/classes in Java is true?
A) An abstract class cannot be instantiated.
B) Constructors can be abstract.
C) A subclass of an abstract class must defined the abstract methods.
D) Static methods may be declared abstract.
85. Which of the following statement is false?
A) The sleep() method should be enclosed in try ……… catch block
B) The yield() method should be enclosed in try ……… catch block.
C) A thread can be temporarily suspended from running by using the wait() method.
D) A suspended thread using suspend() method can be revived using the resume() method.
86. The new operator dynamically allocates …………..for an object and returns a reference to it.
A) classes
B) variables
C) memory
D) none of the above
87. Which of the following statements correctly describes an interface?
A) It’s a concrete class
B) It’s a super class
C) It’s a type of abstract class
D) It’s a subclass
88. What is the priority of the Garbage collector thread of jdk?
A) Low Priority
B) Highest Priority
C) Medium Priority
D) Decided at run time
89. ……………. is a feature that allows one interface to be used for a general class of actions.
A) Class
B) Inheritance
C) Polymorphism
D) Interface
90. The default package that is implicitly called in a java program is ………….
A) java.Lang
B) java.System
C) java.Window
D) java.Lang.System
JAVA Objective type Questions with Answers :
91. Java was developed by the company
A) Sun Micro systems
B) Microsoft
C) Micro tech
D) IBM
92. What is the file extension of compiled java program?
A) .class
B) .java
C) .css
D) .html
93. ……………… keyword is used to invoke the current object.
A) New
B) That
C) This
D) Me
94. Which of the function is used to convert string to Number in java program?
A) to Number()
B) conString()
C) valueOf()
D) toString()
95. What are the part in executing a Java program and their purposes?
A) Java Compiler
B) Java Interpreter
C) Java Pre-processor
D) Directive Pre-processor
96. Method overloading is one of the way that Java supports …………
A) encapsulation
B) class
C) inheritence
D) polymorphism
97. Java support RMI. What does this RMI stands for?
A) Random Memory Interface
B) Remote Method Invocation
C) Random Method Invocation
D) Remote Memory Interface
98. Which of the following represent legal flow control statements?
A) break;
B) break();
C) continue(inner);
D) exit();
99. The keywords reserved but used in the initial version of Java are
A) union
B) const
C) inner
D) goto
100. What is the default return type of main() ..
A) void
B) double
C) float
D) int
101. If m and n are int type variables, what will be the result of the expression m%n when m=-14 and n=-3?
A) 4
B) 2
C) -2
D) -4
102. Consider the following code
if(number>=0)
if(number>0)
system.out.println(“Number is positive”);
else
system.out.println(“Number is negative”);
What will be the output if number is equal to 0?
A) Number is negative
B) Number is positive
C) Both A and B
D) None of the above
103. Consider the following code:
char c=’a’;
switch (c)
{
case ‘a’;
system.out.println(“A”);
case ‘b’;
system.out.println(“B”);
default;
system.out.println(“C”);
}
For this code, which of the following statement is true?
A) Output will be A
B) Output will be A followed by B
C) Output will be A, followed by B, and then followed by C
D) Code is illegal and therefore will not compile
104. Consider the following class definition.
class Student extends String
{
}
What happens when we try to compile this class?
A) Will not compile because class body is not defined
B) Will not compile because the class in not declared public.
C) Will not compile because string is abstract.
D) Will not compile because string is final.
105. What is wrong in the following class definitions?
abstract class print
{
abstract show();
}
class Display extends Print
{
}
A) Nothing is wrong
B) Wrong. Method show() should have a return type
C) Wrong. Method show() is not implemented in Display
D) Wrong. Display does not contain any numbers.
106. What is the error in the following class definitions?
abstract class XY
{
abstract sum(int x, int y){ }
}
A) Class header is not defined properly
B) Constructor is not defined
C) Method is not defined properly
D) No error.
107. Which of the following statements are true?
i) We cannot use abstract classes to instantiate objects directly.
ii) The abstract methods of an abstract class must be defined in its subclass.
iii) We cannot declare abstract constructors.
iv) We may declare abstract static methods.
A) Line i only
B) Line ii only
C) Line i and ii only
D) Line i, ii and iii only
108. We would like to make a member of a class visible in all subclasses regardless of what package they are in. Which one of the following keywords would archive this?
A) Private
B) Protected
C) Public
D) Private Protected
109. The use of protected keyword to a member in a class will restrict its visibility as follows:
A) Visible only in the class and its subclass in the same package.
B) Visible only inside the same package.
C) Visible in all classes in the same package and sub classes in other packages
D) Visible only in the class where it is declared.
110. Consider the following code:
interface Area
{
float compute (float x, float y);
}
class Room implements Area
{
float compute (float x, float y)
{
return(x&y);
}
}
What is wrong with the code?
A) Interface definition is incomplete
B) Method compute() in interface Area should be declared public
C) Method compute() in class Room should be declared public
D) All the above
111. A java program is first ……………. and ……………….
A) executed, run
B) compiled, run
C) run, compiled
D) interpreted, compiled
112. Byte code is also a ………..
A) machine code
B) bit code
C) cryptographic code
D) none
113. A private class is accessible from inside a ……………..
A) package
B) class
C) method
D) none
114. Consider the statement “x=(a>b)?a:b”, then the value of x is 19, if a=19 and b=12
A) true
B) not supported
C) false
D) none of the above
115. Adapter classes are used for ……………
A) code redundancy
B) code reduction
C) code organization
D) none
116. ………………… inheritance is enable by interface in java.
A) min level
B) multiple
C) low level
D) none
117. ……………….. is generated if a button is clicked in AWT.
A) ItemEvent
B) WindowEvent
C) ActionEvent
D) MouseEvent
118. Using which keyword we can access value of the instance and class variables of that class inside the method of that class itself.
A) super
B) final
C) this
D) either super or this
119. If a variable is declared FINAL, it must include ……………………. value.
A) integer
B) number
C) initial
D) float
120. In java, string is a
A) primitive data type
B) abstract data type
C) combination of boolean
D) None of the above
121. Methods can be overloaded with a difference only in the type of the return value
A) Not supported
B) False
C) True
D) None of the above
122. Each method in a java class must have a unique name
A) Not necessarily
B) True
C) False
D) None of the above
123. It is an important feature of java that it always provides a default constructor to a class
A) Not supported
B) False
C) True
D) None of the above
124. If one or more abstract methods are not implemented in an abstract class, then the subclass is also abstract.
A) Not necessarily
B) False
C) True
D) None of the above
125. Life cycle of an applet is described by ……………… methods.
A) six
B) three
C) four
D) five
126. Which of the following is not subclass of “writer” stream.
A) FileWriter
B) LineWriter
C) BufferedWriter
D) PrintWriter
127. In java RMI, stub is located in
A) client machine
B) proxy
C) server
D) none of the above
128. The new keyword will
i) create in instance of an object
ii) create instance of a class
iii) assign memory to an array
iv) call the destructor of a class
A) i and iii
B) ii and iii
C) i and ii
D) ii, iii and iv
129. ODBC stands for
A) Object Data Binding Command
B) Open Database Console
C) Open Database Connectivity
D) Open Database Command
130. Continue statement can be used
i) anywhere inside main method
ii) anywhere inside class
iii) within instance methods
iv) only within looping statements
A) i, ii and iii
B) i and iv
C) only iv
D) ii, iii and iv
131. Which of the following statement is/are true?
i) The name of a java program file must match the name of the class with the extension .java
ii) Two methods cannot have the same name in java
A. i- only
B. ii- only
C. Both i and ii
D. None of the above
132. Which of the following represent(s) of a hexadecimal number?
A. 570
B. (hex)5
C. 0X9F
D. 0X5
133. …….. can appear only where in the body of a java method.
A. definition
B. declaration
C. determine
D. package
134. State whether the following statement are True or False?
i) The modulus operator(%) can be used only with integer operands
ii) Declarations can appear anywhere in the body of a java method
A. i-True, ii-False
B. i-False, ii-True
C. i-True, ii-True
D. i-False, ii-False
135. Which of the following will produce a value of 22 if x=22.9?
A. ceil(x)
B. round(x)
C. rint(x)
D. abs(x)
136. …….. is passed to a method by use of call by reference.
A. Variables
B. Objects
C. Methods
D. Operators
137. Using the keyboard interface you can fully abstract a …
A. Method
B. Keyword
C. Class
D. Variables
138. State True or False for the following statements in java.
i) All the bitwise operators have same level of precedence in java
ii) The default can is always required in the switch selection structure.
A. i-True, ii-False
B. i-False, ii-True
C. i-True, ii-True
D. i-False, ii-False
139. Java is designed for ………. environment of the Internet.
A. Development
B. Deduction
C. Distributed
D. Web Design
140. Which of the following will produce a value of 10 if x=9.7?
A. floor(x)
B. abs(x)
C. rint(x)
D. round(x)
141. Variable declared as ……… do not occupy on a per instance basis.
A. Static
B. Final
C. Abstract
D. Code
142. Which of the following is not keyword?
A. NULL
B. implements
C. protected
D. switch
143. The …… statement is used to terminate a statement sequence.
A. Break
B. Switch
C. Continue
D. Wait
144. Multidimensional arrays are actually ……
A. Arrays of element
B. Arrays of variable
C. Arrays of arrays
D. Arrays of variable
145. Which of the following keywords are used to control access to a class member?
i) default ii) abstract iii) protected iv) interface v) public
A. i, ii and iii only
B. ii, iii and iv only
C. iii, iv and v only
D. ii, iii and v only
146. ……. is used for initialize the value to the string object.
A. Character literals
B. String literals
C. String group literals
D. Group literals
147. Which of the following methods can be used to remove a component from the display?
A. delete()
B. remove()
C. disappear()
D. hide()
148. Which of the following statements are valid array declaration?
i) int number(); ii) float average[ ];
iii) double[]marks; iv) counter int[];
A. i and ii
B. ii and iii
C. iii and iv
D. All i, ii, iii and iv
149. Which of the following methods belong to the String class?
A. length()
B. CompareTo()
C. equals()
D. substring()
E. All of the above
150. Which of the following in NOT represent legal flow control statements?
A. break;
B. break();
C. continue outer;
D. return;
151. Object is an …….. of class.
A. instance
B. implement
C. inheritance
D. invoke
152. ……. is the wrapper class.
A. Random
B. Byte
C. Vector
D. String
153. Class is a …….. entity.
A. logical
B. Physical
C. up normal
D. collection of
154. Which of the following denotes a javadoc comment?
A. //#
B. /*
C. /**
D. //**
155. Object is a …….. entity.
A. normal
B. physical
C. logical
D. normal
156. One interface can inherit another by use of the keyword ……..
A. public
B. extends
C. method name
D. class name
157. ……… must be the first non comment statement in the file
A. package
B. class
C. object
D. declaration
158. In java thread to thread communication is called ….
A. passing
B. sending
C. messaging
D. calling
159. Every method of a ……….. is implicitly final.
A. static class
B. dynamic class
C. final class
D. abstract class
160. The string is defined in ……… name space.
A. java.Lang
B. java.String
C. java.Char
D. java.Awt
161. A ……… object cannot be modified after it is created.
A. double
B. int
C. string
D. main
162. ……… is a special member function.
A. method
B. class
C. use defined function
D. constructor
163. A …….. class may not have any abstract method.
A. abstract
B. static
C. final
D. public
164. Keyword ………. is always a reference to the object.
A. new
B. this
C. invoke
D. class
165. ……… operators are overloaded for string objects?
A. -,+
B. +,=
C. <<,>>
D. ++,–
166. ……. is a small unit of process.
A. method
B. thread
C. applet
D. steam
167. ……. is valid for if statement?
A. An integer expression
B. A Boolean expression
C. A character expression
D. A legal expression
168. Wrapper class is a wrapper around a ……. data type.
A. normal
B. central
C. primitive
D. concrete
169. …….. statement is valid for array declaration.
A. int number();
B. float number();
C. float number[];
D. count int[];
170. ……. operators which concatenates two strings.
A. +
B. ++
C. –
D. +-