[Java]String contains no format specifiers. --> what does it mean? How to fix it?

[apu...@redhat.com]

Hi,

it seems that a new rule is available with latest version.

I have several issue reported as "Printf-style format strings should be used correctly (squid:S3457)"

I don't understand the description and what is wrong in my cases.
There are 2 different cases.

• One is when there is no parameters, reported only with latest SonarLint:
  
• One is when there is a parameter: see https://sonarcloud.io/project/issues?id=camel-lsp-server&issues=AWIpzdqAgrzAwlaaWTrL&open=AWIpzdqAgrzAwlaaWTrL

In the rules description we have:

java.util.Logger logger;
logger.log(java.util.logging.Level.SEVERE, "Result {0}.", myObject.toString()); // Noncompliant; no need to call toString() on objects
logger.log(java.util.logging.Level.SEVERE, "Result.", new Exception()); // compliant, parameter is an exception
logger.log(java.util.logging.Level.SEVERE, "Result '{0}'", 14); // Noncompliant {{String contains no format specifiers.}}

and

java.util.Logger logger;
logger.log(java.util.logging.Level.SEVERE, "Result {0}.", myObject);
logger.log(java.util.logging.Level.SEVERE, "Result {0}'", 14);

What's the difference with my cases?

Can you help me understand what is the correct way to write it?

Regards,

[apu...@redhat.com]

argh realizing that it is recommended to use stackoverflow for this kind of question.

and found the first case which is an already fixed bug on head: https://stackoverflow.com/questions/48683723/sonarqube-string-contains-no-format-specifiers-when-logging-constant-string-m 

I recreated a question there for the second issue: https://stackoverflow.com/questions/50021455/sonarqubejavaprintf-style-format-strings-should-be-used-correctly