Method delete
has a Cognitive Complexity of 6 (exceeds 5 allowed). Consider refactoring. Open
@SuppressWarnings("ResultOfMethodCallIgnored")
private static void delete(File file) {
if (!file.exists()) {
return;
}
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Cognitive Complexity
Cognitive Complexity is a measure of how difficult a unit of code is to intuitively understand. Unlike Cyclomatic Complexity, which determines how difficult your code will be to test, Cognitive Complexity tells you how difficult your code will be to read and comprehend.
A method's cognitive complexity is based on a few simple rules:
- Code is not considered more complex when it uses shorthand that the language provides for collapsing multiple statements into one
- Code is considered more complex for each "break in the linear flow of the code"
- Code is considered more complex when "flow breaking structures are nested"
Further reading
Use "java.nio.file.Files#delete" here for better messages on error conditions. Open
file.delete();
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- Exclude checks
When java.io.File#delete
fails, this boolean
method simply returns false
with no indication of the cause. On
the other hand, when java.nio.file.Files#delete
fails, this void
method returns one of a series of exception types to better
indicate the cause of the failure. And since more information is generally better in a debugging situation, java.nio.file.Files#delete
is
the preferred option.
Noncompliant Code Example
public void cleanUp(Path path) { File file = new File(path); if (!file.delete()) { // Noncompliant //... } }
Compliant Solution
public void cleanUp(Path path) throws NoSuchFileException, DirectoryNotEmptyException, IOException { Files.delete(path); }
Define and throw a dedicated exception instead of using a generic one. Open
throw new RuntimeException(e);
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- Exclude checks
Using such generic exceptions as Error
, RuntimeException
, Throwable
, and Exception
prevents
calling methods from handling true, system-generated exceptions differently than application-generated errors.
Noncompliant Code Example
public void foo(String bar) throws Throwable { // Noncompliant throw new RuntimeException("My Message"); // Noncompliant }
Compliant Solution
public void foo(String bar) { throw new MyOwnRuntimeException("My Message"); }
Exceptions
Generic exceptions in the signatures of overriding methods are ignored, because overriding method has to follow signature of the throw declaration in the superclass. The issue will be raised on superclass declaration of the method (or won't be raised at all if superclass is not part of the analysis).
@Override public void myMethod() throws Exception {...}
Generic exceptions are also ignored in the signatures of methods that make calls to methods that throw generic exceptions.
public void myOtherMethod throws Exception { doTheThing(); // this method throws Exception }
See
- MITRE, CWE-397 - Declaration of Throws for Generic Exception
- CERT, ERR07-J. - Do not throw RuntimeException, Exception, or Throwable
Define and throw a dedicated exception instead of using a generic one. Open
throw new RuntimeException(e);
- Read upRead up
- Exclude checks
Using such generic exceptions as Error
, RuntimeException
, Throwable
, and Exception
prevents
calling methods from handling true, system-generated exceptions differently than application-generated errors.
Noncompliant Code Example
public void foo(String bar) throws Throwable { // Noncompliant throw new RuntimeException("My Message"); // Noncompliant }
Compliant Solution
public void foo(String bar) { throw new MyOwnRuntimeException("My Message"); }
Exceptions
Generic exceptions in the signatures of overriding methods are ignored, because overriding method has to follow signature of the throw declaration in the superclass. The issue will be raised on superclass declaration of the method (or won't be raised at all if superclass is not part of the analysis).
@Override public void myMethod() throws Exception {...}
Generic exceptions are also ignored in the signatures of methods that make calls to methods that throw generic exceptions.
public void myOtherMethod throws Exception { doTheThing(); // this method throws Exception }
See
- MITRE, CWE-397 - Declaration of Throws for Generic Exception
- CERT, ERR07-J. - Do not throw RuntimeException, Exception, or Throwable
Rename this constant name to match the regular expression '^[A-Z][A-Z0-9]*(_[A-Z0-9]+)*$'. Open
private static final String help =
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- Exclude checks
Shared coding conventions allow teams to collaborate efficiently. This rule checks that all constant names match a provided regular expression.
Noncompliant Code Example
With the default regular expression ^[A-Z][A-Z0-9]*(_[A-Z0-9]+)*$
:
public class MyClass { public static final int first = 1; } public enum MyEnum { first; }
Compliant Solution
public class MyClass { public static final int FIRST = 1; } public enum MyEnum { FIRST; }