Avoid empty array allocations in ResolvableType

Avoid allocating empty arrays in a few places in ResolvableType.

Closes spring-projectsgh-33473

spring-core/src/main/java/org/springframework/core/ResolvableType.java

@@ -549,9 +549,14 @@ public ResolvableType[] getInterfaces() {
  ResolvableType[] interfaces = this.interfaces;
  if (interfaces == null) {
  Type[] genericIfcs = resolved.getGenericInterfaces();
- interfaces = new ResolvableType[genericIfcs.length];
- for (int i = 0; i < genericIfcs.length; i++) {
- interfaces[i] = forType(genericIfcs[i], this);
+ if (genericIfcs.length > 0) {
+ interfaces = new ResolvableType[genericIfcs.length];
+ for (int i = 0; i < genericIfcs.length; i++) {
+ interfaces[i] = forType(genericIfcs[i], this);
+ }
+ }
+ else {
+ interfaces = EMPTY_TYPES_ARRAY;
  }
  this.interfaces = interfaces;
  }
@@ -789,16 +794,26 @@ public ResolvableType[] getGenerics() {
  if (generics == null) {
  if (this.type instanceof Class<?> clazz) {
  Type[] typeParams = clazz.getTypeParameters();
- generics = new ResolvableType[typeParams.length];
- for (int i = 0; i < generics.length; i++) {
- generics[i] = ResolvableType.forType(typeParams[i], this);
+ if (typeParams.length > 0) {
+ generics = new ResolvableType[typeParams.length];
+ for (int i = 0; i < generics.length; i++) {
+ generics[i] = ResolvableType.forType(typeParams[i], this);
+ }
+ }
+ else {
+ generics = EMPTY_TYPES_ARRAY;
  }
  }
  else if (this.type instanceof ParameterizedType parameterizedType) {
  Type[] actualTypeArguments = parameterizedType.getActualTypeArguments();
- generics = new ResolvableType[actualTypeArguments.length];
- for (int i = 0; i < actualTypeArguments.length; i++) {
- generics[i] = forType(actualTypeArguments[i], this.variableResolver);
+ if (actualTypeArguments.length > 0) {
+ generics = new ResolvableType[actualTypeArguments.length];
+ for (int i = 0; i < actualTypeArguments.length; i++) {
+ generics[i] = forType(actualTypeArguments[i], this.variableResolver);
+ }
+ }
+ else {
+ generics = EMPTY_TYPES_ARRAY;
  }
  }
  else {