diff --git a/src/main/java/org/openrewrite/staticanalysis/ReplaceCollectToListWithToList.java b/src/main/java/org/openrewrite/staticanalysis/ReplaceCollectToListWithToList.java new file mode 100644 index 000000000..de3db13c3 --- /dev/null +++ b/src/main/java/org/openrewrite/staticanalysis/ReplaceCollectToListWithToList.java @@ -0,0 +1,92 @@ +/* + * Copyright 2025 the original author or authors. + *

+ * Licensed under the Moderne Source Available License (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + *

+ * https://docs.moderne.io/licensing/moderne-source-available-license + *

+ * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.openrewrite.staticanalysis; + +import org.openrewrite.ExecutionContext; +import org.openrewrite.Preconditions; +import org.openrewrite.Recipe; +import org.openrewrite.TreeVisitor; +import org.openrewrite.java.JavaTemplate; +import org.openrewrite.java.JavaVisitor; +import org.openrewrite.java.MethodMatcher; +import org.openrewrite.java.search.UsesJavaVersion; +import org.openrewrite.java.search.UsesMethod; +import org.openrewrite.java.tree.J; + +import java.time.Duration; + +/** + * Replaces Stream.collect(Collectors.toList()) with Stream.toList() + *

+ * [POC] rewrite-maven-plugin: Introduce OpenRewrite by Moderne + * Modernize codebase with Java improvements + * suppression request + * + */ +public class ReplaceCollectToListWithToList extends Recipe { + + private static final MethodMatcher COLLECT_TO_LIST = new MethodMatcher("java.util.stream.Stream collect(java.util.stream.Collector)"); + + @Override + public String getDisplayName() { + return "Replace `Stream.collect(collectors.toList())` with `Stream.toList()`"; + } + + @Override + public String getDescription() { + return "Replace Java 11 `Stream.collect(Collectors.toList())` with Java 16+ `Stream.toList()` for more concise syntax and an unmodifiable return value."; + } + + @Override + public Duration getEstimatedEffortPerOccurrence() { + return Duration.ofMinutes(1); + } + + @Override + public TreeVisitor getVisitor() { + return Preconditions.check(Preconditions.and( + new UsesJavaVersion<>(16), + new UsesMethod<>(COLLECT_TO_LIST)), + new JavaVisitor() { + + private final JavaTemplate template = JavaTemplate + .builder("#{any(java.util.stream.Stream)}.toList()") + .build(); + + @Override + public J visitMethodInvocation(J.MethodInvocation method, ExecutionContext ctx) { + J.MethodInvocation m = (J.MethodInvocation) super.visitMethodInvocation(method, ctx); + + if (COLLECT_TO_LIST.matches(m) && isCollectorsToList(m)) { + maybeRemoveImport("java.util.stream.Collectors"); + return template.apply( + updateCursor(m), + m.getCoordinates().replace(), + m.getSelect() + ); + } + return m; + } + + private boolean isCollectorsToList(J.MethodInvocation method) { + return method.getArguments().get(0) instanceof J.MethodInvocation && + ((J.MethodInvocation) method.getArguments().get(0)).getSimpleName().equals("toList") && + ((J.MethodInvocation) method.getArguments().get(0)).getSelect() != null && + ((J.MethodInvocation) method.getArguments().get(0)).getSelect().toString().equals("Collectors"); + } + }); + } +} diff --git a/src/test/java/org/openrewrite/staticanalysis/ReplaceCollectToListWithToListTest.java b/src/test/java/org/openrewrite/staticanalysis/ReplaceCollectToListWithToListTest.java new file mode 100644 index 000000000..5c4551e14 --- /dev/null +++ b/src/test/java/org/openrewrite/staticanalysis/ReplaceCollectToListWithToListTest.java @@ -0,0 +1,105 @@ +/* + * Copyright 2025 the original author or authors. + *

+ * Licensed under the Moderne Source Available License (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + *

+ * https://docs.moderne.io/licensing/moderne-source-available-license + *

+ * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.openrewrite.staticanalysis; + +import org.junit.jupiter.api.Test; +import org.openrewrite.test.RecipeSpec; +import org.openrewrite.test.RewriteTest; + +import static org.openrewrite.java.Assertions.java; +import static org.openrewrite.java.Assertions.version; + +class InvertReplaceCollectToListWithToListTest implements RewriteTest { + + @Override + public void defaults(RecipeSpec spec) { + spec.recipe(new ReplaceCollectToListWithToList()); + } + + @DocumentExample + @Test + void replacesCollectToList() { + rewriteRun( + version( + //language=java + java( + """ + package com.example; + + import java.util.stream.Collectors; + import java.util.stream.Stream; + + class Example { + public void test() { + Stream.of().collect(Collectors.toList()); + } + } + """, + """ + package com.example; + + import java.util.stream.Stream; + + class Example { + public void test() { + Stream.of().toList(); + } + } + """), + 17)); + } + + @Test + void replacesCollectToListKeepImport() { + rewriteRun( + version( + //language=java + java( + """ + package com.example; + + import java.util.List; + import java.util.stream.Collector; + import java.util.stream.Collectors; + import java.util.stream.Stream; + + class Example { + public void test() { + Collector> list = Collectors.toList(); + Stream.of().collect(list); + Stream.of().collect(Collectors.toList()); + } + } + """, + """ + package com.example; + + import java.util.List; + import java.util.stream.Collector; + import java.util.stream.Collectors; + import java.util.stream.Stream; + + class Example { + public void test() { + Collector> list = Collectors.toList(); + Stream.of().collect(list); + Stream.of().toList(); + } + } + """), + 17)); + } +}