How can I use "`<" and ">`" in javadoc without formatting?

java

javadoc

html-escape-codes

javadoc-tags

byNikita Barsukov·Feb 11, 2025

You can use HTML entities < and > to escape the angle brackets < and > in Javadoc.

Example:

/**
 * Sure this isn't a dating app, but we still get to compare:
 * Is {@code a &lt; b} or {@code a &gt; b}?
 * 
 * @param a first int for consideration
 * @param b second int for selection
 * @return true if {@code a} is indeed less than {@code b}
 */
public boolean isLessThan(int a, int b) {
    return a < b; // No strings attached, just an innocent comparison
}

Under the hood: why escaping is necessary

Direct usage of < and > in Javadoc is not recommended as these are HTML tag indicators. To prevent misinterpretations, we use the magic of HTML escape codes < and >. These codes help < and > to gallivant freely in your Javadoc comments - no misinterpretations, no harsh judgement.

Translating Javadoc speak: {@code} vs. {@literal}

When documenting generic text or non-code elements, {@literal ...} has got your back. On the other hand, {@code ...} is your best friend when you need to illustrate code snippets. For example:

/**
 * When you say "{@literal A&lt;B&gt;C}", no one bats an eye because we respect all data.
 * Conversely, when you say "{@code A&lt;B&gt;C}", everyone judges because we know that's not how code talks.
 */

Multiline code in Javadoc: The `<pre>{@code}</pre>` combo

For multilined code, mixing <pre> tags with {@code} is your ultimate winning move. The <pre> tag helps maintain the formatting, while {@code} ensures < and > can strut about incode style:

/**
 * A bit of deep code talks (it's not as scary as you think):
 * <pre>{@code
 * if (cats &lt; dogs) {
 *     // Sorry cats, dogs are taking over the world!
 * } else if (cats &gt; dogs) {
 *     // A world run by cats? Now that's a funny story.
 * }
 *}</pre>
 */

Deciding whether to use {@code} or {@literal}

Use {@code ...} when your Javadoc docs feature XML snippets or other pieces of code.
Embrace {@literal ...} when your text includes characters like <and >, or if you want these characters to play the hide and seek game in the Javadoc.

Potential pitfalls and solutions

Unescaped < and > may result in compilation errors and broken Javadoc layouts.
Older releases of the Javadoc tool may not recognize {@literal ...} and {@code ...} tags.
Always remember to check the official Java documentation for recent features and compatibility issues.