Replace PartProvider with JavaTemplate

For openrewrite/rewrite#3754

Author: timtebeek

src/main/java/org/openrewrite/java/testing/mockito/AnyStringToNullable.java

@@ -20,8 +20,9 @@
 import org.openrewrite.Recipe;
 import org.openrewrite.TreeVisitor;
 import org.openrewrite.java.JavaIsoVisitor;
+import org.openrewrite.java.JavaParser;
+import org.openrewrite.java.JavaTemplate;
 import org.openrewrite.java.MethodMatcher;
-import org.openrewrite.java.PartProvider;
 import org.openrewrite.java.search.UsesMethod;
 import org.openrewrite.java.tree.J;
 
@@ -32,8 +33,6 @@
  */
 public class AnyStringToNullable extends Recipe {
     private static final MethodMatcher ANY_STRING = new MethodMatcher("org.mockito.Mockito anyString()");
-    private static final String MOCKITO_CLASS_PATH = "mockito-core-3.12";
-    private static J.MethodInvocation nullableStringMethodTemplate = null;
 
     @Override
     public String getDisplayName() {
@@ -53,31 +52,20 @@ public Duration getEstimatedEffortPerOccurrence() {
     @Override
     public TreeVisitor<?, ExecutionContext> getVisitor() {
         return Preconditions.check(new UsesMethod<>(ANY_STRING), new JavaIsoVisitor<ExecutionContext>() {
-
             @Override
             public J.MethodInvocation visitMethodInvocation(J.MethodInvocation method, ExecutionContext ctx) {
                 J.MethodInvocation mi = super.visitMethodInvocation(method, ctx);
-
                 if (ANY_STRING.matches(mi)) {
                     maybeAddImport("org.mockito.ArgumentMatchers", "nullable", false);
                     maybeRemoveImport("org.mockito.Mockito.anyString");
-                    return getNullableMethodTemplate().withPrefix(mi.getPrefix());
+                    return JavaTemplate.builder("nullable(String.class)")
+                            .javaParser(JavaParser.fromJavaVersion().classpathFromResources(ctx, "mockito-core-3.12"))
+                            .staticImports("org.mockito.ArgumentMatchers.nullable")
+                            .build()
+                            .apply(getCursor(), mi.getCoordinates().replace());
                 }
                 return mi;
             }
         });
     }
-
-    private static J.MethodInvocation getNullableMethodTemplate() {
-        if (nullableStringMethodTemplate == null) {
-            nullableStringMethodTemplate = PartProvider.buildPart("import static org.mockito.ArgumentMatchers" +
-                    ".nullable;\n" +
-                    "public class A {\n" +
-                    "    void method() {\n" +
-                    "        Object x = nullable(String.class);\n" +
-                    "    }\n" +
-                    "}", J.MethodInvocation.class, MOCKITO_CLASS_PATH);
-        }
-        return nullableStringMethodTemplate;
-    }
 }

src/test/java/org/openrewrite/java/testing/mockito/AnyStringToNullableTest.java

@@ -24,7 +24,6 @@
 import static org.openrewrite.java.Assertions.java;
 
 class AnyStringToNullableTest implements RewriteTest {
-
     @Override
     public void defaults(RecipeSpec spec) {
         spec