Prior to JDK 6, we can check if a string is empty in 2 ways:
  • if(s != null && s.length() == 0)
  • if(("").equals(s))
Checking its length is more readable and may be a little faster. Starting from JDK 6, String class has a new convenience method isEmpty():
boolean isEmpty()
Returns true if, and only if, length() is 0.
It is just a shorthand for checking length. Of course, if the String is null, you will still get NullPointerException. I don't see much value in adding this convenience method. Instead, I'd like to see a static utility method that also handle null value:
public static boolean notEmpty(String s) {
 return (s != null && s.length() > 0);
}
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Posted by Unknown
Labels: Java/JDK
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When writing javadocs, IntelliJ automatically adds a closing tag for html elements. For instance, after typing <lt>, it automaticaly adds </lt>, or after typing <p>, it adds </p>. It can be annoying since simple html elements like those used in javadocs don't really need ending tags.
To disable javadoc automatic closing tags in IntelliJ, simply go to IntelliJ Preferences -> Editor -> Smart Keys, then on the right panel, uncheck Automatically insert closing tag.

Intellij 14 screenshot:


 Intellij 15 screenshot:

A related note, JDK 8 has tightened javadoc syntax check, and as a result self-closing elements like <p/>, or <br/> are deemed invalid and will cause failures. See JDK-8020619. However, this checking can be disabled by passing nonstandard option -Xdoclint:none to javadoc tool. For official javadoc guidelines, see How to Write Doc Comments for the Javadoc Tool .
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