What is the role of static in java

static is a modifier in Java that declares a class member or method to have static attributes: static variables belong to the class, are loaded when the program starts, and are shared by all instances of the class. Static methods can only access static variables and methods and can be called without an instance of the class. The static code block is executed when the class is loaded and is used to initialize static variables or perform necessary operations when the class is started.

The role of static keyword in Java

What is static?

static is a modifier in Java that declares a class member or method to have static properties.

static variables

• belong to the class, not to instances of the class.
• Loaded when the program starts and destroyed when the program ends.
• Shared by all instances of the class.

static method

• can only access static variables and methods.
• Can be called without an instance of the class.
• is typically used for utility methods or methods related to the operation of the class itself.

static code block

• A code block that is executed when the class is loaded.
• Mainly used to initialize static variables or perform necessary operations when starting a class.

Advantages of static

• Improve performance: Static members are only initialized once, avoiding the overhead of repeated initialization.
• Reduce memory usage: Static members are shared by all instances, reducing memory consumption.
• Convenient maintenance: Centralize management of class-level data and behavior, simplifying maintenance.

Usage scenarios

The following are some common scenarios for using the static keyword:

• Public constants:Declare frequently used values, such as mathematical constants or enumerations.
• Utility class: Create a utility class containing static methods to provide common functions.
• Factory method: Creates new objects without revealing the internal implementation of the class.
• Initialization: Perform necessary initialization operations when the class is loaded.

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