(Sonar) Fixed finding: "Stream.toList() should be used instead of `…

…collectors`" (#430)

## Remediation

This change fixes "`Stream.toList()` should be used instead of
`collectors`" (id =
[java:S6204](https://rules.sonarsource.com/java/RSPEC-6204)) identified
by Sonar.

## Details

This change modernizes a stream's `List` creation to be driven from the
simple, and more readable
[`Stream#toList()`](https://docs.oracle.com/javase/16/docs/api/java.base/java/util/stream/Collectors.html#toList())
method.

Our changes look something like this:

```diff
- List<Integer> numbers = someStream.collect(Collectors.toList());
+ List<Integer> numbers = someStream.toList();
```

<details>
  <summary>More reading</summary>

*
[https://rules.sonarsource.com/java/RSPEC-6204/](https://rules.sonarsource.com/java/RSPEC-6204/)
</details>

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---------

Co-authored-by: pixeebot[bot] <104101892+pixeebot[bot]@users.noreply.github.com>
Co-authored-by: Ryan Dens <[email protected]>

core-codemods/src/main/java/io/codemodder/codemods/VerbTamperingCodemod.java

@@ -10,7 +10,6 @@
 import java.util.Objects;
 import java.util.Optional;
 import java.util.Set;
-import java.util.stream.Collectors;
 import javax.inject.Inject;
 import javax.xml.stream.XMLEventReader;
 import javax.xml.stream.XMLEventWriter;
@@ -62,8 +61,7 @@ private List<CodemodChange> processWebXml(final CodemodInvocationContext context
     Set<Integer> linesAffected = xmlChange.linesAffected();
 
     // add the weaves to the context
-    List<CodemodChange> changes =
-        linesAffected.stream().map(CodemodChange::from).collect(Collectors.toList());
+    List<CodemodChange> changes = linesAffected.stream().map(CodemodChange::from).toList();
 
     // overwrite the previous web.xml with the new one
     Files.copy(xmlChange.transformedXml(), file, StandardCopyOption.REPLACE_EXISTING);
@@ -107,8 +105,6 @@ public String getIndividualChangeDescription(final Path filePath, final CodemodC
 
   @Override
   public List<CodeTFReference> getReferences() {
-    return reporter.getReferences().stream()
-        .map(u -> new CodeTFReference(u, u))
-        .collect(Collectors.toList());
+    return reporter.getReferences().stream().map(u -> new CodeTFReference(u, u)).toList();
   }
 }

framework/codemodder-base/src/main/java/io/codemodder/CLI.java

@@ -485,9 +485,7 @@ public Integer call() throws IOException {
               reportGenerator.createReport(
                   projectDirectory.toPath(),
                   String.join(" ", args),
-                  sarifs == null
-                      ? List.of()
-                      : sarifs.stream().map(Path::of).collect(Collectors.toList()),
+                  sarifs == null ? List.of() : sarifs.stream().map(Path::of).toList(),
                   results,
                   elapsed);
           ObjectMapper mapper = new ObjectMapper();

framework/codemodder-base/src/main/java/io/codemodder/CodemodReporterStrategy.java

@@ -8,7 +8,6 @@
 import java.nio.file.Path;
 import java.util.List;
 import java.util.Objects;
-import java.util.stream.Collectors;
 import java.util.stream.StreamSupport;
 import org.apache.commons.io.IOUtils;
 import org.jetbrains.annotations.NotNull;
@@ -116,9 +115,7 @@ private static CodemodReporterStrategy getCodemodReporterStrategy(
     String change = parent.get("change").asText();
     ArrayNode referencesNode = (ArrayNode) parent.get("references");
     List<String> references =
-        StreamSupport.stream(referencesNode.spliterator(), false)
-            .map(JsonNode::asText)
-            .collect(Collectors.toList());
+        StreamSupport.stream(referencesNode.spliterator(), false).map(JsonNode::asText).toList();
 
     return new CodemodReporterStrategy() {
       @Override

framework/codemodder-base/src/main/java/io/codemodder/DefaultCodemodExecutor.java

@@ -243,6 +243,8 @@ private FilesUpdateResult updateFiles(
     List<Path> filesFailedToChange = List.of();
 
     // update the dependencies in the manifest file if needed
+    // We suppress warnings because we conditionally remove items from this list instance
+    @SuppressWarnings("java:S6204")
     List<DependencyGAV> dependencies =
         codemodChanges.stream()
             .map(CodemodChange::getDependenciesNeeded)
@@ -267,7 +269,7 @@ private FilesUpdateResult updateFiles(
             .map(
                 change ->
                     translateCodemodChangetoCodeTFChange(codeChanger, filePath, change, pkgActions))
-            .collect(Collectors.toList());
+            .toList();
 
     // make sure we add the file's entry first, then the dependency entries, so the causality
     // is clear

framework/codemodder-base/src/main/java/io/codemodder/DefaultXPathStreamProcessor.java

@@ -58,7 +58,7 @@ public Optional<XPathStreamProcessChange> process(
         DocumentHelper.selectNodes(xpathExpression, doc).stream()
             .map(node -> (LocationAwareElement) node)
             .map(element -> new Position(element.getLine(), element.getColumn()))
-            .collect(Collectors.toUnmodifiableList());
+            .toList();
 
     if (httpMethodPositions.isEmpty()) {
       return Optional.empty();
@@ -97,7 +97,7 @@ public Optional<XPathStreamProcessChange> process(
     // remove the empty leftover lines affected by our changes if there are any
     Set<Integer> linesAffected =
         httpMethodPositions.stream().map(pos -> pos.line()).collect(Collectors.toUnmodifiableSet());
-    List<String> lines = transformedXml.lines().collect(Collectors.toUnmodifiableList());
+    List<String> lines = transformedXml.lines().toList();
     List<String> updatedLines = new ArrayList<>(lines.size() - linesAffected.size());
     for (int i = 1; i <= lines.size(); i++) {
       String actualLine = lines.get(i - 1);

framework/codemodder-base/src/main/java/io/codemodder/ParameterModule.java

@@ -6,7 +6,6 @@
 import java.util.Objects;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
-import java.util.stream.Collectors;
 
 /**
  * Responsible for binding {@link Parameter}s to codemods. Also performs validation to ensure
@@ -33,7 +32,7 @@ protected void configure() {
         this.injectableParameters.stream()
             .filter(param -> param.isAnnotationPresent(CodemodParameter.class))
             .filter(param -> param.getType().equals(Parameter.class))
-            .collect(Collectors.toUnmodifiableList());
+            .toList();
 
     for (java.lang.reflect.Parameter param : codemodParameters) {
       CodemodParameter codemodParameter = param.getAnnotation(CodemodParameter.class);

framework/codemodder-base/src/main/java/io/codemodder/RawFileChanger.java

@@ -4,7 +4,6 @@
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.List;
-import java.util.stream.Collectors;
 
 /** Gives access to raw files for performing arbitrary changes. */
 public abstract class RawFileChanger implements CodeChanger {
@@ -45,8 +44,6 @@ public String getIndividualChangeDescription(final Path filePath, final CodemodC
 
   @Override
   public List<CodeTFReference> getReferences() {
-    return reporter.getReferences().stream()
-        .map(u -> new CodeTFReference(u, u))
-        .collect(Collectors.toList());
+    return reporter.getReferences().stream().map(u -> new CodeTFReference(u, u)).toList();
   }
 }

framework/codemodder-base/src/main/java/io/codemodder/javaparser/JavaParserChanger.java

@@ -5,7 +5,6 @@
 import io.codemodder.codetf.CodeTFReference;
 import java.nio.file.Path;
 import java.util.List;
-import java.util.stream.Collectors;
 
 /** Uses JavaParser to change Java source files. */
 public abstract class JavaParserChanger implements CodeChanger {
@@ -41,8 +40,6 @@ public String getIndividualChangeDescription(final Path filePath, final CodemodC
 
   @Override
   public List<CodeTFReference> getReferences() {
-    return reporter.getReferences().stream()
-        .map(u -> new CodeTFReference(u, u))
-        .collect(Collectors.toList());
+    return reporter.getReferences().stream().map(u -> new CodeTFReference(u, u)).toList();
   }
 }

plugins/codemodder-plugin-maven/src/main/java/io/codemodder/plugins/maven/operator/POMOperator.java

@@ -6,7 +6,6 @@
 import java.net.URISyntaxException;
 import java.nio.file.Path;
 import java.util.*;
-import java.util.stream.Collectors;
 import javax.xml.stream.XMLStreamException;
 import org.dom4j.DocumentException;
 import org.jetbrains.annotations.NotNull;
@@ -183,7 +182,7 @@ static Optional<VersionQueryResponse> queryVersions(ProjectModel projectModel)
     if (queryVersionResult.size() == 1) {
       List<VersionDefinition> queryVersionResultList =
           queryVersionResult != null && !queryVersionResult.isEmpty()
-              ? queryVersionResult.stream().collect(Collectors.toList())
+              ? queryVersionResult.stream().toList()
               : Collections.emptyList();
       Version mappedVersion = mapVersion(queryVersionResultList.get(0).getValue());
 

plugins/codemodder-plugin-maven/src/main/java/io/codemodder/plugins/maven/operator/ProjectModelFactory.java

@@ -6,7 +6,6 @@
 import java.net.URL;
 import java.nio.file.Path;
 import java.util.*;
-import java.util.stream.Collectors;
 import org.dom4j.DocumentException;
 
 /**
@@ -47,8 +46,7 @@ public ProjectModelFactory withPomFile(POMDocument pomFile) {
    */
   public ProjectModelFactory withParentPomFiles(Collection<POMDocument> parentPomFiles) {
     this.parentPomFiles =
-        new ArrayList<>(
-            parentPomFiles.stream().filter(Objects::nonNull).collect(Collectors.toList()));
+        new ArrayList<>(parentPomFiles.stream().filter(Objects::nonNull).toList());
     return this;
   }