Quick Answer

Handle unsupported character encoding issues.

Understanding the Issue

This checked exception occurs when an unsupported character encoding is specified for string encoding/decoding operations.

The Problem

This code demonstrates the issue:

Java Error 
String text = "hello";
byte[] bytes = text.getBytes("UTF-32"); // May throw

The Solution

Here's the corrected code:

Java Fixed 
// Solution 1: Use standard charset names
try {
    byte[] bytes = text.getBytes(StandardCharsets.UTF_8);
} catch (UnsupportedEncodingException e) {
    // Will never happen for StandardCharsets
}

// Solution 2: Check supported charsets
if (Charset.isSupported("UTF-32")) {
    byte[] bytes = text.getBytes("UTF-32");
}

// Solution 3: Default encoding with fallback
String encoding = "UTF-32";
try {
    return new String(bytes, encoding);
} catch (UnsupportedEncodingException e) {
    return new String(bytes); // Default charset
}

// Solution 4: Java 7+ Files methods automatically handle encoding
Files.readAllLines(path, StandardCharsets.UTF_8);

Key Takeaways

Prefer StandardCharsets constants and validate encodings when needed.