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Core%20java - Interview Questions and Answers for 'At' - 0 question(s) found - Order By Newest |
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| Q1. 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 block |
| Ans.d. We can create new object through static method or static block |
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| Q2. 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 Method |
| Ans.a. Static Block
Main Method |
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| Q3. 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
Constructor |
| Ans.d. Static Block
Main Method
Instance Initialization Block
Constructor |
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| Q4. 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"); |
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| Q5. 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 null |
| Ans.b. 0 null |
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| Q6. Which of the following is true for == operator ? | Core Java |
| a. For primitives, == checks if the variables on left and right have same data type | b. For primitives, == checks if the variables on left and right have same value | c. For Objects, == checks if the references on left and right have same data type | d. For Objects, == checks if the references on left and right have same value |
| Ans.b. For primitives, == checks if the variables on left and right have same value |
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| Q7. Which of the following is equivalent to following logic ?
Not X && Not Y | Core Java |
| a. x || Y | b. Not(X || Y) | c. Not(X && Y) | d. Not X && Y |
| Ans.b. Not(X || Y) |
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| Q8. Which of the following http response means the resource is not found ? | Java EE |
| a. 500 | b. 200 | c. 404 | d. 400 |
| Ans.c. 404 |
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| Q9. What is Dirty Read in Database Transactions ? | Database |
| a. Data Read by Transaction 2 which hasn't yet updated by Transaction 1 | b. Data Read by Transaction 2 which has been updated and commited by Transaction 1 | c. Data Read by Transaction 2 which has been updated but not commited by Transaction 1 | d. Inability of Transaction 2 to read Data when Transaction 1 is updating. |
| Ans.c. Data Read by Transaction 2 which has been updated but not commited by Transaction 1 |
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| Q10. Which of following annotation is used to initialize objects before executing set of tests ? Reference | Junit |
| a. @Test | b. @Ignore | c. @After | d. @Before |
| Ans.d. @Before |
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| | a. Static members are shared by all objects of the class. | b. We can override static methods. | c. Static methods operate on static variables only. | d. Static Elements are accessed using class name. |
| Ans.b. We can override static methods. |
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| | a. Feature to load the dependencies from Cache | b. Feature to load all objects and relationships in advance before they can be used | c. Feature to not load dependencies and relationship in advance and load when required | d. Feature to not load the dependencies and relationships at all |
| Ans.c. Feature to not load dependencies and relationship in advance and load when required |
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| Q13. Which of the following is not the benefit of Lazy Initialization in Hibernate ? | Hibernate |
| a. Laod When required provides better performance | b. Object stays lighter | c. Less number of Database calls | d. Less load on Database |
| Ans.c. Less number of Database calls |
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| Q14. The use of volatile keyword facilitates .. | Core Java |
| a. Making Use of Cache for better Performance | b. Avoiding use of Cache | c. Making use of Backward as well as Forward Cache | d. Keeping only one copy of variable in Cache |
| Ans.b. Avoiding use of Cache |
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| Q15. Static Polymorphic in Java is achieved through .. | Core Java |
| a. Method Overloading | b. Method Overriding | c. Variable Overloading | d. Variable Overriding |
| Ans.a. Method Overloading |
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| Q16. Which of following are serialized ? | Core Java |
| a. static variables | b. transient variables | c. instance variables | d. method local variables |
| Ans.c. instance variables |
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| Q17. Which of the following is not true for Hibernate Cache ? | Hibernate |
| a. First level cache is enabled by default | b. First level Cache is Session specific | c. First level cache is considered global | d. First level Cache came with Hibernate 1.0 |
| Ans.c. First level cache is considered global |
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| Q18. Which of the following is not an Hibernate Annotation | Hibernate |
| a. @Id | b. @JoinTable | c. @ManyToMany | d. @Autowired |
| Ans.d. @Autowired |
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| Q19. Which of following is not Spring MVC annotation ? | Spring |
| a. @Autowired | b. @Controller | c. @JoinColumn | d. @Transactional |
| Ans.c. @JoinColumn |
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| Q20. In majority of the cases, the following join will give maximum number of results ? Reference | Database |
| a. Inner Join | b. Outer Join | c. Left Join | d. Right Join |
| Ans.b. Outer Join |
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| | a. Left Join and Right Join gives equal number of Results | b. Outer Join and Inner Join gives equal number of Results | c. Inner Join gives maximum number of results records | d. Inner Join gives minimum number of result records |
| Ans.d. Inner Join gives minimum number of result records |
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| Q22. Listeners are example of .. | Design |
| a. Factory design Pattern | b. Abstract Factory Design Pattern | c. Singleton Design Pattern | d. Observer Design Pattern |
| Ans.d. Observer Design Pattern |
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| Q23. Which of the following is a configuration management tool ? | Tool |
| a. Github | b. Jira | c. Tomcat | d. Eclipse |
| Ans.a. Github |
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| Q24. Which of following is not a configuration management tool ? | Tool |
| a. SVN | b. Jira | c. GitHub | d. Clearcase |
| Ans.b. Jira |
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| Q25. Which of the following Design pattern has been used with Hibernate Criteria ? | Hibernate |
| a. Filter | b. Prototype | c. Builder | d. Observer |
| Ans.a. Filter |
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| Q26. Which of following is not core interface of Hibernate ? | Hibernate |
| a. Session | b. Transaction | c. SessionFactory | d. TransactionFactory |
| Ans.d. TransactionFactory |
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| Q27. Which of the following is not true for Prepared Statements ? | Database |
| a. Prepared Statements provides better performance | b. Prepared Statements prevent SQL Injection attacks | c. Prepared Statements provide ORM capabilities | d. Prepared Statement provides DB side caching |
| Ans.c. Prepared Statements provide ORM capabilities |
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| Q28. Which of the following session method is used to disassociate / disconnect all objects from the session Reference | Hibernate |
| a. Clear | b. Evict | c. Close | d. Merge |
| Ans.a. Clear |
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| Q29. Which of the following session method is used to disassociate / disconnect a particular object / entity from the session | Hibernate |
| a. Clear | b. Evict | c. Close | d. Merge |
| Ans.b. Evict |
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| Q30. Which of following is not the resolution for preventing LazyInitializationException? | Hibernate |
| a. Set fetch=FetchType.EAGER for Dependent entity mapping | b. Make sure that we are accessing the dependent objects before closing the session | c. Make sure that we are accessing the dependent objects after closing the session | d. Wrap the complete access within Transaction |
| Ans.c. Make sure that we are accessing the dependent objects after closing the session |
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