V6046. Incorrect format. Consider checking the N format items of the 'Foo' function.


The analyzer has detected a possible error related to use of formatting methods: String.format, System.out.format, System.err.format, etc. The format string does not correspond with actual arguments passed to the method.

Here are some simple examples:

Unused arguments.

int A = 10, B = 20;
double C = 30.0;
System.out.format("%1$s < %2$s", A, B, C);

Format item '%3$s' is not specified, so variable 'C' won't be used.

Possible correct versions of the code:

//Remove extra argument
System.out.format("%1$s < %2$s", A, B); 

//Fix format string
System.out.format("%1$s < %2$s < %3$s", A, B, C); 

Number of arguments passed is less than expected.

int A = 10, B = 20;
double C = 30.0;
System.out.format("%1$s < %2$s < %3$s", A, B); 

A much more dangerous situation occurs when a function receives fewer arguments than expected. This leads to an exception.

Possible correct versions of the code:

//Add missing argument
System.out.format("%1$s < %2$s < %3$s", A, B, C); 

//Fix indices in format string
System.out.format("%1$s < %2$s", A, B); 

The analyzer doesn't output the warning given that:

  • The number of format items specified matches the number of arguments.
  • The format object is used a number of times:
int row = 10;
System.out.format("Line: %1$s; Index: %1$s", row);

Bugs Found

Checked Projects
367
Collected Errors
13 552