แสดงกระทู้

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - Gurpreetsingh

หน้า: [1]
1
Around Suannan / What is the difference between composition and inheritance?
« เมื่อ: เมษายน 26, 2024, 03:46:59 pm »
Both composition and inheritance are fundamental concepts of object-oriented programing, which define relationships between classes and their objects. Composition is the process of constructing complex objects by combining simpler ones. Inheritance is the process of creating a new (derived) class that inherits attributes and behaviors of an existing (base) class. The main difference is in the way they establish relationships between objects and classes. Java Course in Pune

A class can contain an instance of another as a "member" with composition. The containing class is in a relationship of "has-a" with the contained class. A Car class, for example, may contain instances from the Engine, Wheel and Chassis classes. These components are usually created and managed in the Car class. Composition provides greater flexibility and modularity as objects contained within the class can be swapped out or modified easily without affecting the containing one.

Contrary to inheritance, the "is-a relationship" between classes is established by inheritance. Inheritance lets a class inherit methods and attributes from another class. This promotes code reuse and extends the functionality of the base. A Truck class can inherit from the Vehicle class and gain access to all of its methods and properties. It is easier to organize code and create a hierarchy among classes with inheritance. However, it can also lead to a tight class hierarchy and rigidity.

Both composition and inheritance promote code reuse and modular design. However, their approaches to establishing relationships among classes are different. Composition focuses on combining simple objects to create complex ones. This promotes flexibility and modularity. Contrastingly, inheritance is focused on creating new classes from existing ones. This encourages code reuse and hierarchical relations. Both concepts are useful tools for object-oriented programs, with their own strengths and uses.

2
Around Suannan / What is deadlock in Java? How can it be prevented?
« เมื่อ: เมษายน 05, 2024, 03:50:23 pm »
Deadlock in Java is in situations where two threads are locked indefinitely, waiting for one other to release the resources they require. This is typically the case when multiple threads gain a lock on resources in a manner that results in a circular dependency. For example, when Thread A has Lock 1 and tries to get Lock 2 while Thread B holds Lock 2 and tries to get Lock 1, a deadlock scenario occurs since neither can continue to move forward until the other has released its lock. Java Course in Pune

Preventing deadlock in Java involves several strategies. One method is to ensure that threads acquire locks in the same sequence. Thus circular dependencies are eliminated. Another option is to employ the timeout mechanism while acquiring locks. This allows threads to identify deadlock situations and take corrective actions like releasing the locks and then retrying after. Also using concurrency tools at a higher level that are provided by Java such as the java. util. concurrent package, which includes classes such as Executor, Concurrent Hash Map as well as Count Down Latch and can help you avoid common mistakes that can lead to deadlocks.

3
Around Suannan / Explain the concept of generics in Java
« เมื่อ: มีนาคม 22, 2024, 04:05:55 pm »
Generics is a Java feature that was introduced in Java 5. It allows developers to create interfaces, classes, and methods that operate on types as parameters. Generics are primarily used to improve code reuse and type checking at compile time by allowing methods and classes to accept any data type. Java Classes in Pune

Here is a summary of the key features of Java generics:

Type Variables: Generics introduce type variables (also known as type parameters) which are specified in angle brackets ("<>" after the class, interface, or method name. These type parameters are placeholder types which will be replaced with concrete types if the generic class interface or method is used.

Generic classes and interfaces: By utilizing type parameters, developers can create generic classes and a standardized interface that can be used with any type of data. The classes and interfaces created can be instantiated using specific types.

Generic methods: Java supports both generic classes and interfaces as well as generic methods. These methods have their type parameters independent of class/interface type parameters.

Type Security: The compiler can detect and report any type errors during compilation. This reduces runtime errors due to mismatched types.

Type inference: The Java compiler can often infer type arguments from the context. This allows developers to omit type parameters explicitly in some situations.

Generics are a powerful tool in Java that allows you to create reusable code, which is type-safe and can be used with many different data types. They also allow for compile-time checking of type. They are widely used in the Java Collections Framework and are an essential part of modern Java Programming.

4
Around Suannan / What is a constructor in Java? How is it different from a method?
« เมื่อ: มีนาคม 08, 2024, 04:13:02 pm »
In the realm of Java programming constructors play a crucial role in initializing objects. They are essential parts of classes and are called every time an object from the class is constructed. Constructors are frequently compared to methods, however they have an entirely distinct function and possess distinct characteristics. Java Classes in Pune

Understanding Constructors: In Java constructors, it is a specific type of method that's automatically invoked whenever an object is created. Its primary purpose is to initiate an object that has been created. Constructors are the same type as classes and do not come with a return type, and not even the void. They are different from normal methods.

The characteristics of constructors:

Initialization: Constructors are typically used to establish the condition of an object. They establish the initial values for instance variables and also perform the necessary tasks of setting up.

Name: Constructors share similar names to the classes they are part of. This convention of naming helps Java differentiate constructors and other techniques.

The No-Return Type Contrary to methods, constructors cannot return types. They are not able to return values and even the void.

Invocation: Constructors can be invoked with the new keyword each time an object belonging to the class is constructed. They are automatically invoked when the object is created.

Overloading: Constructors can be overloaded and a class may contain multiple constructors that have different parameter lists. Java utilizes the parameters provided to decide which constructor to call in a manner that is based on the arguments provided when creating objects.

The default constructor is If a class doesn't specify explicitly any constructors Java offers a default constructor. This default constructor will initialize instance variables using default values (0 null, null, or false, based on the nature of the variable). Java Course in Pune

Access Modifiers: Constructors can be assigned access modifiers, such as the following: public, private, protected, or default package-private. This lets you control the level of access to constructors.

หน้า: [1]