Adding MigrateClassNewInstanceToGetDeclaredConstructorNewInstance recipe. Fixes #51

Author: pway99

src/main/java/org/openrewrite/java/migrate/lang/MigrateClassNewInstanceToGetDeclaredConstructorNewInstance.java

@@ -0,0 +1,63 @@
+package org.openrewrite.java.migrate.lang;
+
+import org.openrewrite.ExecutionContext;
+import org.openrewrite.Recipe;
+import org.openrewrite.internal.lang.Nullable;
+import org.openrewrite.java.ChangeMethodName;
+import org.openrewrite.java.JavaIsoVisitor;
+import org.openrewrite.java.MethodMatcher;
+import org.openrewrite.java.search.UsesMethod;
+import org.openrewrite.java.tree.J;
+import org.openrewrite.java.tree.JavaType;
+import org.openrewrite.java.tree.TypeUtils;
+
+public class MigrateClassNewInstanceToGetDeclaredConstructorNewInstance extends Recipe {
+    private static final MethodMatcher NEW_INSTANCE_MATCHER = new MethodMatcher("java.lang.Class newInstance()");
+    @Override
+    public String getDisplayName() {
+        return "Use `Class#getDeclaredConstructor().newInstance()`";
+    }
+
+    @Override
+    public String getDescription() {
+        return "`Class#newInstance()` was deprecated in Java 9.";
+    }
+
+    @Override
+    protected UsesMethod<ExecutionContext> getSingleSourceApplicableTest() {
+        return new UsesMethod<>("java.lang.Class newInstance()");
+    }
+
+    @Override
+    protected NewInstanceToDeclaredConstructorVisitor getVisitor() {
+        return new NewInstanceToDeclaredConstructorVisitor();
+    }
+
+    private static class NewInstanceToDeclaredConstructorVisitor extends JavaIsoVisitor<ExecutionContext> {
+        private final JavaType exType = JavaType.buildType("java.lang.Exception");
+        private final JavaType thType = JavaType.buildType("java.lang.Throwable");
+        private static final ChangeMethodName TO_DECLARED_CONS_NEW_INSTANCE = new ChangeMethodName("java.lang.Class newInstance()", "getDeclaredConstructor().newInstance", null);
+
+        @Override
+        public J.MethodInvocation visitMethodInvocation(J.MethodInvocation method, ExecutionContext executionContext) {
+            J.MethodInvocation mi = super.visitMethodInvocation(method, executionContext);
+            if (NEW_INSTANCE_MATCHER.matches(mi)) {
+                J.Try tri = getCursor().firstEnclosing(J.Try.class);
+                J.MethodDeclaration md = getCursor().firstEnclosing(J.MethodDeclaration.class);
+                if ((tri != null && tri.getCatches().stream().anyMatch(c -> isExceptionType(c.getParameter().getType())))
+                        || (md != null && md.getThrows() != null && md.getThrows().stream().anyMatch(nt -> isExceptionType(nt.getType())))) {
+                    J.MethodInvocation modifiedMethodInvocation = (J.MethodInvocation)TO_DECLARED_CONS_NEW_INSTANCE.getVisitor().visit(mi,executionContext);
+                    if (modifiedMethodInvocation != null) {
+                        mi = modifiedMethodInvocation;
+                    }
+                }
+            }
+            return mi;
+        }
+
+        private boolean isExceptionType(@Nullable JavaType type) {
+            return TypeUtils.isOfType(type,exType)
+                    || TypeUtils.isOfType(type, thType);
+        }
+    }
+}

src/main/resources/META-INF/rewrite/java-lang-apis.yml

@@ -27,6 +27,7 @@ recipeList:
   - org.openrewrite.java.migrate.lang.MigrateRuntimeVersionSecurityToUpdate
   - org.openrewrite.java.migrate.lang.MigrateSecurityManagerMulticast
   - org.openrewrite.java.migrate.lang.MigrateClassLoaderDefineClass
+  - org.openrewrite.java.migrate.lang.MigrateClassNewInstanceToGetDeclaredConstructorNewInstance
 
 ---
 type: specs.openrewrite.org/v1beta/recipe

src/test/kotlin/org/openrewrite/java/migrate/lang/JavaLangAPIsTest.kt

@@ -94,31 +94,6 @@ class JavaLangAPIsTest : JavaRecipeTest {
         """
     )
 
-    @Disabled
-    @Test
-    fun classNewInstanceToGetDeclaredConstructorNewInstance() = assertChanged(
-        before = """
-            package com.abc;
-
-            class A {
-               public void test() {
-                   Class<?> clazz = Class.forName("org.openrewrite.Test");
-                   clazz.newInstance();
-               }
-            }
-        """,
-        after = """
-            package com.abc;
-
-            class A {
-               public void test() {
-                   Class<?> clazz = Class.forName("org.openrewrite.Test");
-                   clazz.getDeclaredConstructor().newInstance();
-               }
-            }
-        """
-    )
-
     @Test
     fun runtimeVersionMajorToFeature() = assertChanged(
         before = """

src/test/kotlin/org/openrewrite/java/migrate/lang/MigrateClassNewInstanceToGetDeclaredConstructorNewInstanceTest.kt

@@ -0,0 +1,81 @@
+package org.openrewrite.java.migrate.lang
+
+import org.junit.jupiter.api.Test
+import org.openrewrite.Recipe
+import org.openrewrite.java.JavaRecipeTest
+
+@Suppress("deprecation")
+class MigrateClassNewInstanceToGetDeclaredConstructorNewInstanceTest : JavaRecipeTest {
+    override val recipe: Recipe
+        get() = MigrateClassNewInstanceToGetDeclaredConstructorNewInstance()
+
+    @Test
+    fun doesNotThrowExceptionOrThrowable() = assertUnchanged(
+        before = """
+            package com.abc;
+
+            class A {
+               public void test() throws ClassNotFoundException, InstantiationException, IllegalAccessException {
+                   Class<?> clazz = Class.forName("org.openrewrite.Test");
+                   clazz.newInstance();
+               }
+            }
+        """
+    )
+
+    @Test
+    fun methodThrowsThrowable() = assertChanged(
+        before = """
+            package com.abc;
+
+            class A {
+               public void test() throws Throwable {
+                   Class<?> clazz = Class.forName("org.openrewrite.Test");
+                   clazz.newInstance();
+               }
+            }
+        """,
+        after = """
+            package com.abc;
+
+            class A {
+               public void test() throws Throwable {
+                   Class<?> clazz = Class.forName("org.openrewrite.Test");
+                   clazz.getDeclaredConstructor().newInstance();
+               }
+            }
+        """
+    )
+
+    @Test
+    fun tryBlockCatchesException() = assertChanged(
+        before = """
+            package com.abc;
+
+            class A {
+                public void test() {
+                    try {
+                        Class<?> clazz = Class.forName("org.openrewrite.Test");
+                        clazz.newInstance();
+                    } catch (Exception ex) {
+                        System.out.println(ex.getMessage());
+                    }
+                }
+            }
+        """,
+        after = """
+            package com.abc;
+
+            class A {
+                public void test() {
+                    try {
+                        Class<?> clazz = Class.forName("org.openrewrite.Test");
+                        clazz.getDeclaredConstructor().newInstance();
+                    } catch (Exception ex) {
+                        System.out.println(ex.getMessage());
+                    }
+                }
+            }
+        """
+    )
+}