<p>Since Checkstyle 5.0</p><p> Checks that any combination of String literals is on the left side of an equals() comparison. Also checks for String literals assigned to some field (such as <code>someString.equals(anotherString = "text")</code>). </p><p> Rationale: Calling the <code>equals()</code> method on String literals will avoid a potential NullPointerException. Also, it is pretty common to see null checks right before equals comparisons, which is not necessary in the example below. </p><p> For example, this code: </p><pre><code> String nullString = null; nullString.equals("My_Sweet_String"); </code></pre><p>should be refactored to:</p><pre><code> String nullString = null; "My_Sweet_String".equals(nullString); </code></pre>

<p> Checks that local, non-<code>final</code> variable names conform to a format specified by the format property. A catch parameter is considered to be a local variable. </p>

<p> Checks that local, non-<code>final</code> variable names conform to a format specified by the format property. A catch parameter is considered to be a local variable. </p>

<p>Since Checkstyle 3.0</p><p> Checks the placement of right curly braces (<code>'}'</code>) for if-else, try-catch-finally blocks, while-loops, for-loops, method definitions, class definitions, constructor definitions, instance and static initialization blocks. The policy to verify is specified using the property <code> option</code>. For right curly brace of expression blocks please follow issue <a href="https://github.com/checkstyle/checkstyle/issues/5945">#5945</a>. </p>

<p>Since Checkstyle 3.0</p><p> Checks for braces around code blocks. </p>

<p>Since Checkstyle 5.0</p><p> A check for detecting that matches across multiple lines. Works with any file type. </p><p> Rationale: This check can be used to when the regular expression can be span multiple lines. </p>