More than 3000 questions in repository. There are more than 900 unanswered questions. Click here and help us by providing the answer. Have a video suggestion. Click Correct / Improve and please let us know.
Ans. Open the AWS CloudFormation console at https://console.aws.amazon.com/cloudformation . Create a new stack by using one of the following options: Choose Create Stack. This is the only option if you have a currently running stack.
Help us improve. Please let us know the company, where you were asked this question :
Ans. Yes an application can have configuration stored at multiple places. Factors that could facilitate such a design could be
1. Type of config information - We may have a case to store confidential information differently than other regular config value
2. Environment - We may like to have a base config ( defined in application package ) and then a different override mechanism in different environments.
3. Centralization - Sometime some configs need to be shared across application and hence centralized.
4. Testing - Testing against config may not be possible in some enviornments in certain cases and hence additional config store might be kept for testing purpose only.
Help us improve. Please let us know the company, where you were asked this question :
Ans. Assigning a value of one type to a variable of another type is known as Type Casting.
Example :
int x = 10;
byte y = (byte)x;
In Java, type casting is classified into two types, Widening Casting(Implicit) widening-type-conversion and Narrowing Casting (Explicitly done) narrowing-type-conversion.
Widening or Automatic type converion - Automatic Type casting take place when,the two types are compatible and the target type is larger than the source type
Example :
public class Test {
public static void main(String[] args) {
int i = 100;
long l = i; //no explicit type casting required
float f = l;//no explicit type casting required
System.out.println("Int value " i);
System.out.println("Long value " l);
System.out.println("Float value " f);
}
}
Narrowing or Explicit type conversion - When you are assigning a larger type value to a variable of smaller type, then you need to perform explicit type casting.
Example :
public class Test{
public static void main(String[] args) {
double d = 100.04;
long l = (long)d; //explicit type casting required
int i = (int)l;//explicit type casting required
System.out.println("Double value " d);
System.out.println("Long value " l);
System.out.println("Int value " i);
}
}
Help us improve. Please let us know the company, where you were asked this question :
Ans. OAuth is an open-standard authorization protocol or framework that describes how unrelated servers and services can safely allow authenticated access to their assets without actually sharing the initial, related, single logon credential. Like using Google or Facebook to login to something.
Help us improve. Please let us know the company, where you were asked this question :
Q19. While working on a web application, you are informed that there is no new data in Database for last few hours ? How would you go about debugging this problem ?
Ans. Will look into access logs to see if web application is getting any traffic. If not , then will inform the server support team.
Will look into intermediary infrastructure , queues , streams etc to see if there is any choke or throttle there.
If there is any throttle at any point, would make request for either debugging the cause or increasing the infrastructure. For ex - increasing shards in Kinesis.
Help us improve. Please let us know the company, where you were asked this question :
Ans. // Java code for serialization and deserialization
// of a Java object
import java.io.*;
class Demo implements java.io.Serializable
{
public int a;
public String b;
// Default constructor
public Demo(int a, String b)
{
this.a = a;
this.b = b;
}
}
class Test
{
public static void main(String[] args)
{
Demo object = new Demo(1, "geeksforgeeks");
String filename = "file.ser";
// Serialization
try
{
//Saving of object in a file
FileOutputStream file = new FileOutputStream(filename);
ObjectOutputStream out = new ObjectOutputStream(file);
// Method for serialization of object
out.writeObject(object);
out.close();
file.close();
System.out.println("Object has been serialized");
}
catch(IOException ex)
{
System.out.println("IOException is caught");
}
Demo object1 = null;
// Deserialization
try
{
// Reading the object from a file
FileInputStream file = new FileInputStream(filename);
ObjectInputStream in = new ObjectInputStream(file);
// Method for deserialization of object
object1 = (Demo)in.readObject();
in.close();
file.close();
System.out.println("Object has been deserialized ");
System.out.println("a = " object1.a);
System.out.println("b = " object1.b);
}
catch(IOException ex)
{
System.out.println("IOException is caught");
}
catch(ClassNotFoundException ex)
{
System.out.println("ClassNotFoundException is caught");
}
}
}
Help us improve. Please let us know the company, where you were asked this question :
Q26. Suppose we have a string "Java is object oriented language" and we have to reverse every alternate word in string. How would we do that using Java program.
Ans. OOPs or Object Oriented Programming is a Programming model which is organized around Objects instead of processes. Instead of a process calling series of processes, this model stresses on communication between objects. Objects that all self sustained, provide security by encapsulating it's members and providing abstracted interfaces over the functions it performs. OOP's facilitate the following features
1. Inheritance for Code Reuse
2. Abstraction for modularity, maintenance and agility
3. Encapsulation for security and protection
4. Polymorphism for flexibility and interfacing
Help us improve. Please let us know the company, where you were asked this question :