Different exception types in Java and how to handle them

There are two types of exceptions in Java: unchecked exceptions (RuntimeException) and checked exceptions (Exception). Unchecked exceptions do not need to be declared or caught, while checked exceptions need to be declared or caught in order to be handled. With try-catch blocks, you can handle exceptions, prevent program crashes, and provide meaningful error information. The practical case shows how to handle file reading exception IOException through try-catch block.

Different exception types in Java and how to handle them

Introduction

Exceptions are events in a Java program that cannot execute normally. They are raised at runtime and provide information about the error. Understanding the different types of exceptions and knowing how to handle them is critical to writing robust, reliable programs.

Common exception types

1. RuntimeException

• Unchecked exception that does not need to be declared or caught .
• For example: NullPointerException, IndexOutOfBoundsException

##2. Exception

Checked exceptions need to be declared or caught.
• For example:
• IOException, SQLException

##Exception handling

Exceptions can be passed

try-catch

Block processing: <div class="code" style="position:relative; padding:0px; margin:0px;"><pre class='brush:java;toolbar:false;'>try { // 代码可能引发异常 } catch (ExceptionClassName e) { // 捕获并处理异常 }</pre><div class="contentsignin">Copy after login</div></div>

Practical case: Handling file read exceptions

The following code demonstrates how to handle

IOException

Exception, which may be thrown while reading a file: <div class="code" style="position:relative; padding:0px; margin:0px;"><pre class='brush:java;toolbar:false;'>import java.io.File; import java.io.FileNotFoundException; import java.util.Scanner; public class FileReading { public static void main(String[] args) { try { // 打开文件 File file = new File(&quot;data.txt&quot;); Scanner scanner = new Scanner(file); // 读取并打印文件内容 while (scanner.hasNextLine()) { System.out.println(scanner.nextLine()); } scanner.close(); } catch (FileNotFoundException e) { // 处理文件未找到异常 e.printStackTrace(); } } }</pre><div class="contentsignin">Copy after login</div></div>

Conclusion

Understanding the different exception types and how to handle them is essential for writing robust Java programs important. By using

try-catch

blocks, exceptions can be handled gracefully, preventing program crashes and providing meaningful error information.

The above is the detailed content of Different exception types in Java and how to handle them. For more information, please follow other related articles on the PHP Chinese website!