Usage of keywords in java

The keyword is a reserved identifier of Java with a specific meaning and cannot be used as other names. There are 53 keywords in total, divided into data types, modifiers, control flow, exception handling, and other categories. They are used to define data types, control program flow, handle exceptions, and define classes and interfaces. For example, "int" defines a data type, "public" controls access permissions, "if" controls program flow, "try-catch" handles exceptions, and "class" defines a class.

Usage of keywords in Java

What are keywords?

Keywords are pre-reserved identifiers in the Java programming language that have specific meanings and uses. They cannot be used as names of variables, methods, or classes.

Types of keywords

The Java language has 53 keywords, which are divided into the following categories:

• Data types : byte, short, int, long, float, double, char, boolean
• Modifiers: public, protected, private, static, final, abstract, synchronized, volatile, transient
• Control flow: if, else, while, do, for, break, continue, return
• Exception handling: try, catch, finally, throw, throws
• Others:class,interface,enum,package,import,extends,implements

Use of keywords

Keywords have the following uses in Java code:

• Defining data types: Declare the data type of a variable or parameter.
• Specify access permissions: Control access permissions for classes, methods and variables.
• Control program flow: Determine the path of program execution.
• Handling exceptions: Handle and report errors.
• Define classes and interfaces: Create custom data types and behaviors.

Examples

Here are some examples of keywords in Java code:

• Data Type:

  <code class="java">int age = 25;</code>

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• Modifier:

  <code class="java">public class Person {
  private String name;
  }</code>

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• Control flow:

  <code class="java">if (age > 18) {
  System.out.println("Adult");
  }</code>

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• Exception handling:

  <code class="java">try {
  int result = 10 / 0;
  } catch (ArithmeticException e) {
  System.out.println("Division by zero");
  }</code>

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• Others:

  <code class="java">class Car extends Vehicle {
  // Custom class logic
  }</code>

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Note:

• The capitalization of keywords must be correct, otherwise the compiler will report an error.
• Keywords cannot be overwritten or renamed.
• Certain keywords (such as static and final) can be used as the name of methods or variables, but this is not recommended because it can lead to confusion.

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