Exception class must have at least one constructor with signature public Constructor(Throwable, String, Object...) or public Constructor(String, Object...)

[dgroup]

Summary

Key	Value
Rule	NoMandatoryConstructorInExceptionClass
Ruleset	io/github/dgroup/arch4u/pmd/arch4u-ruleset.xml
Category	Design
Framework	N/A
Since	0.1.0
Incidents in past at my experience	100+

Why?

When we are going to throw the custom exceptions, we have to assemble the message, such constructors in exceptions will make code cleaner:

class MyException extends Exception {

    /**
     * The constructor that supports exception message assembling.
     * The arguments might be omitted.
     * 
     * @pattern The exception message pattern.
     * @args    The arguments to assemble the exception message
     * @see String#format
     */
    public MyException(String pattern, Object... args) {
         super(String.format(pattern, args));
    }

    /**
     * The constructor that supports exception message assembling.
     * The arguments might be omitted.
     * 
     * @pattern The exception message pattern.
     * @args    The arguments to assemble the exception message
     * @see String#format
     */
    public MyException(Throwable cause, String pattern, Object... args) {
         super(String.format(pattern, args), cause);
    }
}

and use case will be

throw new MyException(
    "Unable to process order '%s' for '%s' at '%s'", 
    orderId, userId, System.getProperty("server.name")
);

// or

try {
    ...
} catch(SomeException cause) {
   throw new MyException(
      cause, "Unable to process order '%s' for '%s' at '%s'", 
      orderId, userId, System.getProperty("server.name")
   );
}