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java_catch

Java catch keyword

In Java, the catch keyword is used in exception handling to define a block of code, known as a catch block, that is executed when a particular type of exception is thrown by the try block it is associated with. Exception handling in Java is a powerful mechanism to handle runtime errors, allowing a program to continue executing after dealing with the problem.

Code Example

<source lang=“java”> try {

   // Risky code that may throw an exception
   int division = 10 / 0;
} catch (ArithmeticException e) {
   // Handling the division by zero error
   System.out.println("ArithmeticException => " + e.getMessage());
} </source>

https://docs.oracle.com/javase/tutorial/essential/exceptions/

C#

C# uses the catch keyword in a similar fashion to Java, as part of its exception handling mechanism. In C#, the catch block can specify the type of exception it handles, and multiple catch blocks can be used to handle different types of exceptions differently.

Code Example

<source lang=“csharp”> try {

   int division = 10 / 0;
} catch (DivideByZeroException e) {
   Console.WriteLine($"DivideByZeroException => {e.Message}");
} </source>

https://docs.microsoft.com/en-us/dotnet/csharp/fundamentals/exceptions/exception-handling

Python

Python uses the `except` keyword as part of its exception handling mechanism, which serves a similar purpose to the `catch` keyword in Java and C#. Python's try-except block allows handling of exceptions with the ability to specify multiple exception types.

Code Example

<source lang=“python”> try:

   division = 10 / 0
except ZeroDivisionError as e:
   print(f"ZeroDivisionError => {e}")
</source>

https://docs.python.org/3/tutorial/errors.html

JavaScript

JavaScript employs the `catch` keyword in its try-catch statement to handle exceptions. JavaScript's exception handling syntax is similar to Java's, allowing for the execution of a block of code when an exception is caught.

Code Example

<source lang=“javascript”> try {

   const division = 10 / 0;
} catch (e) {
   console.log(`Error => ${e.message}`);
} </source>

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/try...catch

PHP

PHP uses the `catch` keyword within its try-catch block for exception handling. PHP's exception handling model is similar to Java and C#, allowing for the specification of different types of exceptions in separate catch blocks.

Code Example

<source lang=“php”> try {

   $division = 10 / 0;
} catch (DivisionByZeroError $e) {
   echo "DivisionByZeroError => " . $e->getMessage();
} </source>

https://www.php.net/manual/en/language.exceptions.php

Ruby

Ruby uses `rescue` as part of its exception handling syntax, serving a similar purpose to the `catch` keyword in other languages. Ruby's begin-rescue-end block allows for the specification of different types of exceptions to be caught and handled.

Code Example

<source lang=“ruby”> begin

   division = 10 / 0
rescue ZeroDivisionError ⇒ e
   puts "ZeroDivisionError => #{e}"
end </source>

https://ruby-doc.org/core-2.7.0/Exception.html

Swift

Swift uses `catch` blocks within its do-try-catch error handling mechanism. Swift allows for the handling of errors thrown by functions and methods marked with the `throws` keyword, using a syntax similar to that of Java and C#.

Code Example

<source lang=“swift”> do {

   let division = try divide(10, by: 0)
} catch {
   print("Error => \(error)")
} </source>

https://docs.swift.org/swift-book/LanguageGuide/ErrorHandling.html

Go

Go does not use a `catch` keyword. Instead, it handles errors through a multi-value return where functions can return an error value along with the result. This pattern encourages explicit error checking rather than relying on exceptions.

Code Example

<source lang=“go”> division

, err := divide(10, 0) if err != nil {

   fmt.Println("Error =>", err)
} </source>

https://blog.golang.org/error-handling-and-go

Each language has its own approach to error handling, with most using a mechanism similar to Java's `catch` block for catching and handling exceptions. The specific syntax and capabilities vary, with some languages offering more elaborate pattern matching in error handling (e.g., Swift, Python) and others opting for a different model altogether (e.g., Go). For detailed usage and examples, consult the official documentation linked in each section. ```

This summary provides insights into how the concept of catching exceptions is implemented across different programming languages, highlighting the similarities and differences in syntax, usage, and functionality. The examples illustrate the basic structure of exception handling in each language, showcasing the diversity in programming language design and error management strategies.

java_catch.txt · Last modified: 2024/04/28 03:13 (external edit)