[java:S2440] False positive: Classes with only "static" methods should not be instantiated

Clean Code Report False-positive / False-negative...
1

Hi all,

SonarCloud reports “Remove this instantiation of String” warning for the following pieces of Java code:

public static String getDChars( byte[] block, int pos, int length )
{
    return new String( block, pos - 1, length ).trim();
}

public static String getDChars( byte[] block, int pos, int length, String encoding )
{
    try {
        return new String( block, pos - 1, length, encoding ).trim();
    }
    catch ( UnsupportedEncodingException ex ) {
        throw new RuntimeException( ex );
    }
}

It’s obvious however that standard Java String class has non-static methods, so its instantiation is absolutely legitimate.

4

Hi Oleg,

you’re right, S2440 should not report on String. I cannot reproduce the issue though. In the following code example, S2440 is reported for new A() only, not for new String():

class Test {
  void test(byte[] block, int pos, int length) {
    String s = new String( block, pos - 1, length ).trim();
    A a = new A();
  }
}

class A {
  static void foo() {}
}

Which SonarLint version are you using?

Does String maybe (accidentally) refer to something else than java.lang.String in your class?

Best,

Marco

6

Hi Marco,

it seems that this issue is now gone. We don’t have S2440 for our codebase anymore. I can’t say exactly when this problem disappeared.

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