Interview Questions and Answers - Order By Rating Q1661. What is Associativity while evaluating a Java statement ? Core Java
Ans. Associativity determines whether an expression is evaluated left-right or right-left. When an expression has two operators with the same precedence, the expression is evaluated according to its associativity. Help us improve. Please let us know the company, where you were asked this question : Like Discuss Correct / Improve  associativity  expression evaluation  operatorRelated Questions Q1662. What is a package and what are its advantages ? Core Java
Ans. Package is a namespace that organizes a set of related classes.
Advantages of Packages
1. Better Organization of classes.
2. Saves from the problem of duplicate names as duplicate class names are allowed across different packages. Help us improve. Please let us know the company, where you were asked this question : Like Discuss Correct / Improve  package  advantages of packages Asked in 1 Companies Basic Related Questions Can I import same package/class twice? Will the JVM load the package twice at runtime? Is it a good practice to use Asterick(*) in import statement to load multiple packages with single import statement ? Do we need to import java.lang package ? How can I change the default location of the generated jar when I command "mvn package"? What is a Cursor ? Name few classes that are part of java.io package ? Name few classes that are part of java.lang package ? Name few classes that are part of java.util package ? What is the package name for CertStoreParameters class? Q1663. When String literals are compared using ==, they always returns true if the string values are same because .. Reference Core Java
a. of overridden compareTo method b. of overridden compare method c. of String Pool d. == means that the object contents are equalAns.c. of String Pool
Q1664. Which of the following is true ? Core Java
a. Composition is Tightly Bound b. Inheritance is Tightly Bound c. Object can only hold reference of only one other object d. A Class cannot be extended by multiple classesAns.b. Inheritance is Tightly Bound
a. x==y on all literals always returns false b. x.equals(y) on all literals always returns false c. if x.equals(y) returns true, x==y returns true too d. if x.equals(y) returns false, x==y returns trueAns.c. if x.equals(y) returns true, x==y returns true too
a. Constructor without parameters declared by user b. Constructor provided by Java if no constructor is declared c. Constructor with empty body d. All of the aboveAns.b. Constructor provided by Java if no constructor is declared
Q1667. How can we create objects if we make the constructor private ? Core Java
a. We can't create objects if constructor is private b. We can only create objects if we follow singleton pattern c. We can only create one object d. We can create new object through static method or static blockAns.d. We can create new object through static method or static block
Q1668. What will be the output of following ?
String str1 = new String("String1");
String str2 = new String("String1");
System.out.print(str1 == str2);
System.out.print(str1.equals(str2));
str1 = str2;
System.out.print(str1 == str2); Core Java
a. falsetruetrue b. truetruetrue c. truetruefalse d. falsetruefalseAns.a. falsetruetrue
Q1669. What will be the output of following code ?
String str1 = "String1";
String str2 = "String1";
System.out.print(str1 == str2);
System.out.print(str1.equals(str2));
str1 = str2;
System.out.print(str1 == str2); Core Java
a. falsetruetrue b. falsefalsetrue c. truetruetrue d. falsefalsefalseAns.c. truetruetrue
Q1670. What will be the output of following code ?
String str1 = "String1";
String str2 = "String2";
str1.concat("String3");
System.out.print(str1);
System.out.print(str2);
Core Java
a. String1String2 b. String1String3String3 c. String1String3String1String3 d. String1String1Ans.a. String1String2
Q1671. What will be the output of following code ?
String str1 = "String1";
String str2 = "String2";
str1=str1.concat("String3");
System.out.print(str1);
System.out.print(str2); Core Java
a. String1String2 b. String1String3String2 c. String1String2String3 d. String1Stringg3String1Ans.b. String1String3String2
Q1672. Which method needs to be implemented if a class is implementing comparable interface ? Core Java
a. comp b. compare c. compareTo d. compareEqualsAns.c. compareTo
Q1673. Which of the following is false ? Core Java
a. A Class cannot override both hashcode and equals method. b. A class can override both hashcode and equals method. c. A Class must override hashCode method if its overridding equal method. d. A Class can override hashCode even if its not overridding equals method.Ans.a. A Class cannot override both hashcode and equals method.
a. interface b. abstract class c. final class d. util classAns.d. util class
Q1675. Which of the following can throw ClassCastException ? Core Java
a. UpCasting b. DownCasting c. Casting to incompatible data type d. Casting to StringsAns.b. DownCasting
a. final instance methods b. final static methods c. non final instance methods d. non final static methodsAns.c. non final instance methods
Q1677. x instanceOf y returns false .. Core Java
a. if x is an instance of y class b. if x is an instance of class implementing y interface c. if x is an instance of class extending y class d. if x is an instance of Class which is a parent of Y classAns.d. if x is an instance of Class which is a parent of Y class
a. java.lang.Object b. java.lang.Thread c. java.lang.Runnable d. java.lang.ImplementAns.a. java.lang.Object
Q1679. if classes B and C extends Class A, Which of the following initialization is correct ? Core Java
a. B b = new C(); b. C c = new B(); c. B b = new A(); d. A a = new B();Ans.d. A a = new B();
Q1680. If X implements Y and Y extends Z, Which of the following initialization is correct ? Core Java
a. X x = new Y(); b. X x = new Z(); c. Z z = new Y(); d. Z z = new X();Ans.d. Z z = new X();
Q1681. If class A implements X interface, and Class B implements Y interface, and X is the parent of Y, Which of the following initialization is correct ? Core Java
a. A a = new B(); b. Y y = new A(); c. X x = new B(); d. Y y = new A();Ans.c. X x = new B();
Q1682. What will be the output of executing following class ?
public class BuggyBread {
static {
System.out.println("Static Block");
}
{
System.out.println("Initialization Block");
}
BuggyBread(){
System.out.println("Constructor");
}
public static void main(String[] args){
System.out.println("Main Method");
}
}
Core Java
a. Static Block
Main Method b. Static Block
Instance Initialization Block
Main Method c. Static Block
Constructor
Main Method d. Static Block
Instance Initialization Block
Constructor
Main MethodAns.a. Static Block
Main Method
Q1683. What will be the output upon executing following class ?
public class BuggyBread {
static {
System.out.println("Static Block");
}
{
System.out.println("Instance Initialization Block");
}
BuggyBread(){
System.out.println("Constructor");
}
public static void main(String[] args){
System.out.println("Main Method");
new BuggyBread();
}
} Core Java
a. Instance Initialization Block
Constructor
Static Block
Main Method b. Static Block
Instance Initialization Block
Constructor
Main Method c. Main Method
Static Block
Instance Initialization Block
Constructor d. Static Block
Main Method
Instance Initialization Block
ConstructorAns.d. Static Block
Main Method
Instance Initialization Block
Constructor
Q1684. With the following code, Which is a valid way to initialize ?
public class BuggyBread {
private String element1;
private String element2;
private BuggyBread(String element1, String element2){
this.element1 = element1;
this.element2 = element2;
}
public static class Builder {
private String element1;
private String element2;
Builder(BuggyBread buggybread){
element1 = buggybread.element1;
element2 = buggybread.element2;
}
Builder withElement1(String element1){
this.element1 = element1;
return this;
}
Builder withElement2(String element2){
this.element2 = element2;
return this;
}
BuggyBread build(){
BuggyBread buggybread = new BuggyBread(element1,element2);
return buggybread;
}
}
} Core Java
a. BuggyBread buggybread = new BuggyBread(); b. BuggyBread buggybread = new BuggyBread("element1","element2"); c. BuggyBread.Builder builder = new BuggyBread.Builder(); d. BuggyBread.Builder builder = new BuggyBread.Builder("element1","element2");Ans.d. BuggyBread.Builder builder = new BuggyBread.Builder("element1","element2");
Q1685. What will be the output of following code ?
public class BuggyBread {
private int x;
private int y;
BuggyBread(int x,int y){};
public static void main(String[] args){
BuggyBread buggybread = new BuggyBread();
System.out.println(buggybread.x);
}
} Reference Core Java
a. 0 b. null c. compilation error due to uninitialized element d. compilation error due to constructorAns.d. compilation error due to constructor
Q1686. What will be the output of following ?
public class BuggyBread {
private int x;
private Integer y;
BuggyBread(int x,int y){};
public static void main(String[] args){
BuggyBread buggybread = new BuggyBread(1,2);
System.out.println(buggybread.x);
System.out.println(buggybread.y);
}
} Reference Core Java
a. 0 0 b. 0 null c. null 0 d. null nullAns.b. 0 null
Q1687. What will be the output of following code ?
public class BuggyBread {
private int x;
private Integer y;
private BuggyBread(int x,int y){};
public static void main(String[] args){
BuggyBread buggybread = new BuggyBread(1,2);
System.out.println(buggybread.x);
}
} Core Java
a. compilation error due to private constructor b. compilation error due to uninitialized elements c. 0 null d. 0 0Ans.c. 0 null
Q1688. What will be the output of following code ?
public class BuggyBread {
private int x;
private BuggyBread(int x){
x = x;
};
public static void main(String[] args){
BuggyBread buggybread = new BuggyBread(5);
System.out.println(buggybread.x);
}
}
Core Java
a. compilation error b. undefined c. 0 d. 5Ans.c. 0
Q1689. What will be the output of exceuting main method ?
public static void main(String[] args){
List list = new ArrayList();
list.add(1);
list.add(2);
list.add(3);
System.out.println(list);
} Core Java
a. 1,2,3 b. Order cannot be determined c. compilation error d. 3,2,1Ans.a. 1,2,3
Q1690. What will be the output upon executing main method ?
public static void main(String[] args){
Set set = new HashSet();
set.add(1);
set.add(2);
set.add(3);
System.out.println(set);
} Core Java
a. 1,2,3 b. Order cannot be determined c. Compilation error d. 3,2,1Ans.b. Order cannot be determined