NoGetMessageInThrow
Since Checkstyle 13.3.0
Description
Checks that throw statements within catch blocks do not use
the caught exception's getMessage() call when the thrown exception
is the same type as the caught exception, as rethrowing the same
exception type with its own message is redundant.
Rationale: When throwing an exception of the same type as the caught exception and including the caught exception's message via getMessage(), the information is redundant. The original exception should be rethrown directly, or a different exception type should be used.
Example of violations:
catch (IOException ex) {
throw new IOException("Error: " + ex.getMessage()); // violation
}
Correct usage:
catch (IOException ex) {
throw new RuntimeException("Error: " + ex.getMessage(), ex); // OK, different type
}
catch (IOException ex) {
throw new IOException("Error processing file", ex); // OK, no getMessage()
}
Examples
To configure the check:
<module name="Checker">
<module name="TreeWalker">
<module name="NoGetMessageInThrow"/>
</module>
</module>
Example:
class Example1 {
void method1() throws IOException {
try {
throw new IOException();
} catch (IOException ex) {
// violation below, 'ex.getMessage()' is redundant
throw new IllegalStateException("Error: " + ex.getMessage(), ex);
}
}
void method2() throws IOException {
try {
throw new IOException();
} catch (IOException ex) {
// OK, provides context without redundant message
throw new IllegalStateException("Error processing file", ex);
}
}
}
Example of Usage
Violation Messages
All messages can be customized if the default message doesn't suit you. Please see the documentation to learn how to.
Package
com.puppycrawl.tools.checkstyle.checks.coding