Summary

Make MethodTypeDesc::descriptorString an abstract method and no longer provides the default implementation.

Problem

The implementation of MethodTypeDesc::descriptorString needs lazy cache for better performance and done in MethodTypeDescImpl class. The default implementation of MethodTypeDesc::descriptorString is redundant since MethodTypeDescImpl is the only implementation class of MethodTypeDesc sealed interface.

Solution

Move the implementation of descriptorString into MethodTypeDescImpl, and make MethodTypeDesc::descriptorString abstract.

Specification

@@ -195,13 +195,7 @@ public sealed interface MethodTypeDesc
      * @return the method type descriptor string
      * @jvms 4.3.3 Method Descriptors
      */
-    default String descriptorString() {
-        return String.format("(%s)%s",
-                             Stream.of(parameterArray())
-                                   .map(ClassDesc::descriptorString)
-                                   .collect(Collectors.joining()),
-                             returnType().descriptorString());
-    }
+    String descriptorString();

     /**
      * Returns a human-readable descriptor for this method type, using the