Linux – Filesystem test suites

One approach is to use a regular expression, like so:

re='^[0-9]+$'
if ! [[ $yournumber =~ $re ]] ; then
   echo "error: Not a number" >&2; exit 1
fi

If the value is not necessarily an integer, consider amending the regex appropriately; for instance:

^[0-9]+([.][0-9]+)?$

...or, to handle numbers with a sign:

^[+-]?[0-9]+([.][0-9]+)?$

To run a single test class Airborn's answer is good.

With using some command line options, which found here, you can simply do something like this.

gradle test --tests org.gradle.SomeTest.someSpecificFeature
gradle test --tests *SomeTest.someSpecificFeature
gradle test --tests *SomeSpecificTest
gradle test --tests all.in.specific.package*
gradle test --tests *IntegTest
gradle test --tests *IntegTest*ui*
gradle test --tests *IntegTest.singleMethod
gradle someTestTask --tests *UiTest someOtherTestTask --tests *WebTest*ui

From version 1.10 of gradle it supports selecting tests, using a test filter. For example,

apply plugin: 'java'

test {
  filter {
    //specific test method
      includeTestsMatching "org.gradle.SomeTest.someSpecificFeature"

     //specific test method, use wildcard for packages
     includeTestsMatching "*SomeTest.someSpecificFeature"

     //specific test class
     includeTestsMatching "org.gradle.SomeTest"

     //specific test class, wildcard for packages
     includeTestsMatching "*.SomeTest"

     //all classes in package, recursively
     includeTestsMatching "com.gradle.tooling.*"

     //all integration tests, by naming convention
      includeTestsMatching "*IntegTest"

     //only ui tests from integration tests, by some naming convention
     includeTestsMatching "*IntegTest*ui"
   }
}

For multi-flavor environments (a common use-case for Android), check this answer, as the --tests argument will be unsupported and you'll get an error.