How do I handle exceptions in Java?

I want to learn how to handle exceptions in Java. What are the best practices and could someone give examples of handling common types of exceptions?

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In Java, exception handling is performed using the try-catch-finally blocks: ```java try { // Code that might throw an exception } catch (ExceptionType1 e) { // Handle ExceptionType1 } catch (ExceptionType2 e) { // Handle ExceptionType2 } finally { // Optional block, always executed whether an exception arises or not. } ``` Here, you replace `ExceptionType1` and `ExceptionType2` with the exceptions you want to catch. The order matters: the Virtual Machine starts with the first `catch` block and tries to match the thrown `Exception` type with the type being caught. General `Exception` types should be last. Here's a handling 'FileNotFoundException': ```java try { File file = new File("nonexistentfile.txt"); FileReader fileReader = new FileReader(file); } catch ( e) { System.out.println("The file does not exist."); } ``` Best Practices: 1. **Specificity**: Catch only those exceptions that you can actually handle. 2. **Avoid empty catch blocks**: Catching an exception and doing nothing isn't recommended, as it makes debugging difficult. 3. **Use finally for clean-up**: `finally` block should be used for the clean-up code. 4. **Prefer Unchecked Exceptions**: Unchecked exceptions represent conditions that reflect errors in your program's logic and cannot be recovered from at runtime. 5. **Don’t catch the `Exception` class**: Catching `Exception` will also catch any subclasses — effectively defeating the purpose of your specific catch blocks. Remember, the purpose of exception handling is to maintain the flow of the program and deal with problems in a controlled manner.
Answered on August 5, 2023.
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