20+ Galaxy Surfactants Interview Questions and Answers

Using Java 8 Streams API to print single occurrences of names in an ArrayList of Strings.

• Use stream() method on the ArrayList to create a stream of elements.

• Use filter() method to filter out elements that occur more than once.

• Use distinct() method to get only unique elements.

• Use forEach() method to print each unique element.

Reverse the year of birth and name, then print them in that order.

• Reverse the year of birth using StringBuilder.reverse() method

• Reverse the name using StringBuilder.reverse() method

• Print the reversed year of birth followed by the reversed name

Code to print each name and the number of occurrences in an ArrayList of Strings.

• Iterate through the ArrayList and use a HashMap to store the count of each name.

• Print each name along with its count from the HashMap.

Interfaces and Abstract classes in Java are used for achieving abstraction and defining contracts for classes to implement.

• Interfaces in Java are like blueprints for classes, defining methods that must be implemented by classes that implement the interface.

• Abstract classes are classes that cannot be instantiated and can have both abstract and concrete methods.

• Example of an interface in Java: public interface Shape { double calculateArea(); double calculatePerimeter(); }

• Exampl...read more

Lambda expressions in Java are a concise way to represent anonymous functions.

• Lambda expressions are used to provide implementation of functional interfaces.

• They enable you to treat functionality as a method argument, or code as data.

• Syntax: (parameters) -> expression or (parameters) -> { statements; }

• Example: (int a, int b) -> a + b

Functional interfaces in Java are interfaces with only one abstract method, used for lambda expressions and functional programming.

• Functional interfaces have only one abstract method, but can have multiple default or static methods.

• They are used for lambda expressions and functional programming in Java.

• Examples include java.lang.Runnable, java.util.Comparator, and java.util.function.Function.

Android Studio is an Integrated Development Environment (IDE) for Android app development.

• Android Studio is developed by Google and is the official IDE for Android app development.

• It provides a user-friendly interface for coding, debugging, and testing Android apps.

• Android Studio includes various tools such as a layout editor, code editor, emulator, and more.

• Before Android Studio, developers used Eclipse with the Android Development Tools (ADT) plugin for app development.

Truncate is a DDL command that removes all records from a table, while delete is a DML command that removes specific records.

• Truncate is faster than delete as it does not log individual row deletions.

• Truncate resets identity columns, while delete does not.

• Joins in SQL: Inner join, outer join (left, right, full), cross join, self join.

• Languages in SQL: Data Definition Language (DDL), Data Manipulation Language (DML), Data Control Language (DCL), Transaction Control Language (T...read more

Threads in Java are lightweight sub-processes that allow concurrent execution within a single process.

• Threads allow multiple tasks to be executed simultaneously in a Java program.

• Threads share the same memory space and resources within a process.

• Example: Creating a new thread using the Thread class or implementing the Runnable interface.

Streams in Java are sequences of elements that support functional-style operations such as filter, map, reduce, etc.

• Streams are not data structures, but rather a way to interact with collections of objects.

• They allow for efficient processing of large amounts of data.

• Streams can be sequential or parallel, allowing for concurrent processing.

• Example: List names = Arrays.asList("Alice", "Bob", "Charlie"); Stream stream = names.stream();

Areas in OSPF are used to divide a large network into smaller, more manageable subnetworks.

• Areas reduce the amount of routing information that needs to be exchanged between routers.

• They also improve network scalability and reduce the impact of network failures.

• For example, a large organization with multiple campuses might use different areas for each campus.

• This allows for more efficient routing and easier troubleshooting.

• Areas are identified by a unique 32-bit number called ...read more

Different types of charts require different data types to plot them.

• Line charts require numerical data

• Bar charts require categorical data

• Pie charts require numerical data that adds up to 100%

• Scatter plots require numerical data for both x and y axes

• Heat maps require numerical data for both x and y axes, and a third numerical value for the color intensity

• Bubble charts require numerical data for both x and y axes, and a third numerical value for the size of the bubbles

ACL AD value and AS number are related to network security and routing protocols.

• ACL AD value is the Access Control List Administrative Distance value, which is used to determine the priority of a particular ACL entry in case of multiple entries matching a packet.

• AS number is the Autonomous System number, which is used in Border Gateway Protocol (BGP) to identify a group of networks under a single administrative domain.

• ACL AD value and AS number are both important in network ...read more

STP, OSPF, and BGP are routing protocols used in computer networks.

• STP (Spanning Tree Protocol) is used to prevent loops in Ethernet networks.

• OSPF (Open Shortest Path First) is a link-state routing protocol used in IP networks.

• BGP (Border Gateway Protocol) is used to exchange routing information between different autonomous systems.

• STP and OSPF are used in local area networks (LANs), while BGP is used in wide area networks (WANs).

Inter VLAN routing is the process of forwarding network traffic between different VLANs.

• Inter VLAN routing can be achieved through a router or a layer 3 switch.

• It requires the use of a routing protocol such as OSPF or EIGRP.

• VLANs must be configured with unique IP subnets to enable inter VLAN routing.

• ACLs can be used to control traffic flow between VLANs.

• Inter VLAN routing can improve network performance and security by segregating traffic.

• Example: A company may have separate ...read more

There are two types of IP routing: static and dynamic.

• Static routing involves manually configuring the routes in the routing table.

• Dynamic routing uses protocols to automatically update the routing table.

• Examples of dynamic routing protocols include OSPF, BGP, and RIP.

• Static routing is simpler and more secure, but less flexible than dynamic routing.

Collection interface is a framework in Java that represents a group of objects.

• Collection interface is part of Java's Collections Framework.

• It provides a unified architecture for representing and manipulating collections of objects.

• Examples of classes that implement Collection interface are ArrayList, LinkedList, and HashSet.

Routing protocols are used to determine the best path for data to travel between network devices.

• Routing protocols are used in computer networks to exchange information about available routes.

• They help routers determine the best path for data to travel between devices.

• Examples of routing protocols include OSPF, BGP, and RIP.

APIs are sets of protocols and tools for building software applications.

• API stands for Application Programming Interface

• APIs allow different software applications to communicate with each other

• APIs can be used to access data or functionality from a third-party service

• APIs can be RESTful or SOAP-based

• Examples of APIs include Google Maps API, Twitter API, and Facebook API

ROC and AUC are performance metrics used in binary classification models.

• ROC (Receiver Operating Characteristic) is a curve that plots the true positive rate against the false positive rate at different classification thresholds.

• AUC (Area Under the Curve) is the area under the ROC curve and is a measure of the model's ability to distinguish between positive and negative classes.

• ROC and AUC are commonly used to evaluate the performance of binary classification models and compa...read more

Meter Base IDF is an identification number used to uniquely identify a meter base in a utility system.

• Meter Base IDF stands for Meter Base Identification

• It is a unique number assigned to each meter base in a utility system

• The IDF helps in accurately identifying and tracking meter bases

• It is used for billing purposes and maintenance of the utility system

• Meter Base IDF can be found on the meter base itself or in utility records

Clustering techniques are used to group similar data points together based on their characteristics.

• Clustering is an unsupervised learning technique

• K-means, hierarchical, and DBSCAN are popular clustering algorithms

• Clustering can be used for customer segmentation, anomaly detection, and image segmentation

Routed protocols are network protocols that are used to send data between different networks.

• Routed protocols use routing tables to determine the best path for data to travel between networks

• Examples of routed protocols include IP (Internet Protocol) and IPv6

• Routed protocols are used in contrast to bridged protocols, which are used to send data within the same network

EBGP and IBGP are two types of Border Gateway Protocol used in networking.

• EBGP stands for External BGP and is used for communication between different autonomous systems.

• IBGP stands for Internal BGP and is used for communication within the same autonomous system.

• EBGP uses different metrics to determine the best path for routing traffic between autonomous systems.

• IBGP uses the same metrics as the internal routing protocol to determine the best path for routing traffic within t...read more

Costing sheets are created by gathering all relevant cost information and organizing it in a structured format.

• Gather all cost information related to the project or product

• Organize the costs into categories such as labor, materials, overhead, etc.

• Calculate the total cost for each category and for the project as a whole

• Include any additional costs such as taxes, shipping, or fees

• Ensure all calculations are accurate and up to date