child of #14942
violate the non-use of the lambda parameters. They should be unnamed.
Note: The lambda parameters in the check are the parameters of lambda expressions only. The unused pattern variables in the case label of the switch rule are not a target for this check.
Config
$ cat config.xml
<?xml version="1.0"?>
<!DOCTYPE module PUBLIC
"-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
"https://checkstyle.org/dtds/configuration_1_3.dtd">
<module name="Checker">
<module name="TreeWalker">
<module name="UnusedLambdaParameterShouldBeUnnamed"/>
</module>
</module>
Example
public class Test {
void test(Object obj) {
List<String> list = List.of("a", "b", "c");
List<String> Xss = list.stream().map(character -> "x").toList(); // violation
List<String> Xs = list.stream().map(_-> "x").toList();
}
}
Expected Output
$ java -jar checkstyle-10.19.0-all.jar -c config.xml Test.java
Starting audit...
[ERROR] D:\Test.java:4:45:Unused lambda parameter should be unnamed [UnusedLambdaParameterShouldBeUnnamed]
Audit done.
Checkstyle ends with 1 errors.
child of #14942
violate the non-use of the lambda parameters. They should be unnamed.
Note: The lambda parameters in the check are the parameters of lambda expressions only. The unused pattern variables in the case label of the switch rule are not a target for this check.
Config
Example
Expected Output