Groovy: Use @Canonical to Get Compiler-generated Equals, HashCode and ToString
Groovy makes it extremely easy to create Java beans with getters, setters, equals, hashCode, and toString:
You can then do:
As you might have noticed, you may provide your own implementation of toString and reuse the auto-generated toString by calling
@groovy.transform.Canonical
class Call {
def method
def args
/* // custom impl. reusing the auto-generated one:
String toString() {
_toString().replaceFirst("^.*?Call", "")
}*/
}
You can then do:
// Auto-gen. constr. with positional arguments:
def call1 = new Call("someMethod", "someArgs")
def call2 = new Call(method: "someMethod", args: "someArgs")
assert call1.getMethod() == call1.method
assert call2.equals(call1)
assert ([call1, call2] as Set).size() == 1 // hashCode
As you might have noticed, you may provide your own implementation of toString and reuse the auto-generated toString by calling
_toString()
.
References
JavaDoc for @Canonical. You can also use separately any of: @ToString. @EqualsAndHashCode, @TupleConstructor. And may be check also the other available AST annotations such as Immutable and Synchronized and perhaps also groovy.beans's Bindable and Vetoable annotations, if you need true Java Beans.Are you benefitting from my writing? Consider buying me a coffee or supporting my work via GitHub Sponsors. Thank you!