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Replace java.lang.ref.Reference.clone() with constructor call

org.openrewrite.java.migrate.ReferenceCloneMethod

The recipe replaces any clone calls that may resolve to a java.lang.ref.Reference.clone() or any of its known subclasses: java.lang.ref.PhantomReference, java.lang.ref.SoftReference, and java.lang.ref.WeakReference with a constructor call passing in the referent and reference queue as parameters.

Recipe source​

GitHub, Issue Tracker, Maven Central

This recipe is available under the Moderne Source Available License.

Example​

Before​
import java.lang.ref.WeakReference;
import java.lang.ref.SoftReference;
import java.lang.ref.PhantomReference;

class Foo {
    void foo() throws Exception{
        WeakReference<Object> ref = new WeakReference<Object>(null);
        WeakReference<Object> ref1 = (WeakReference<Object>) ref.clone();
        SoftReference<Object> ref3 = new SoftReference<Object>(null);
        SoftReference<Object> ref4 = (SoftReference<Object>) ref3.clone();
        PhantomReference<Object> ref5 = new PhantomReference<Object>(null,null);
        PhantomReference<Object> ref6 = (PhantomReference<Object>) ref5.clone();
    }
 }
After​
import java.lang.ref.WeakReference;
import java.lang.ref.SoftReference;
import java.lang.ref.PhantomReference;

class Foo {
    void foo() throws Exception{
        WeakReference<Object> ref = new WeakReference<Object>(null);
        WeakReference<Object> ref1 = new WeakReference<Object>(ref, new ReferenceQueue<>());
        SoftReference<Object> ref3 = new SoftReference<Object>(null);
        SoftReference<Object> ref4 = new SoftReference<Object>(ref3, new ReferenceQueue<>());
        PhantomReference<Object> ref5 = new PhantomReference<Object>(null,null);
        PhantomReference<Object> ref6 = new PhantomReference<Object>(ref5, new ReferenceQueue<>());
    }
 }

Usage​

This recipe has no required configuration options. It can be activated by adding a dependency on org.openrewrite.recipe:rewrite-migrate-java in your build file or by running a shell command (in which case no build changes are needed):

  1. Add the following to your build.gradle file:
build.gradle
plugins {
    id("org.openrewrite.rewrite") version("7.5.0")
}

rewrite {
    activeRecipe("org.openrewrite.java.migrate.ReferenceCloneMethod")
    setExportDatatables(true)
}

repositories {
    mavenCentral()
}

dependencies {
    rewrite("org.openrewrite.recipe:rewrite-migrate-java:3.8.0")
}
  1. Run gradle rewriteRun to run the recipe.

See how this recipe works across multiple open-source repositories​

Run this recipe on OSS repos at scale with the Moderne SaaS.

The community edition of the Moderne platform enables you to easily run recipes across thousands of open-source repositories.

Please contact Moderne for more information about safely running the recipes on your own codebase in a private SaaS.

Data Tables​

Source files that had results​

org.openrewrite.table.SourcesFileResults

Source files that were modified by the recipe run.

Column NameDescription
Source path before the runThe source path of the file before the run. null when a source file was created during the run.
Source path after the runA recipe may modify the source path. This is the path after the run. null when a source file was deleted during the run.
Parent of the recipe that made changesIn a hierarchical recipe, the parent of the recipe that made a change. Empty if this is the root of a hierarchy or if the recipe is not hierarchical at all.
Recipe that made changesThe specific recipe that made a change.
Estimated time savingAn estimated effort that a developer to fix manually instead of using this recipe, in unit of seconds.
CycleThe recipe cycle in which the change was made.

Contributors​

Anu Ramamoorthy, Tim te Beek, Jonathan Schnéider