To fix this problem, you must remove the annotation, create a getter for the property you want to use and annotate the getter instead.

[[mutable_type_with_setter]]
== Mutable type with setter

This error indicates that a property of "mutable" type is also providing a setter.

            this.next = next;
        }

        @Override
        public void invoke(MethodInvocation method) throws Throwable {
            if (method.isGetter()) {
                if (properties.containsKey(method.getName())) {
                    method.setResult(properties.get(method.getName()));
                    return;
                }

                }
            }

            task copy(type: MyCopy) {
                inputDirectory = file("input")
                nonIncrementalInput = file("nonIncremental.txt")
                outputDirectory.${setter}(file("build/output"))
            }
        """
        def inputFilePath = "in/some/input.txt"
        def nonIncrementalInput = file("nonIncremental.txt")
        nonIncrementalInput.text = "original"

    if (isWindows()) {
      return; // TODO: b/136041958 - Running very slowly on Windows CI.
    }
    final CyclicBarrier barrier =
        new CyclicBarrier(
            6 // for the setter threads
                + 50 // for the listeners
                + 50 // for the blocking get threads,
                + 1); // for the main thread

        }
        testNg.addListener((Object) adaptListener(new TestNGTestResultProcessorAdapter(resultProcessor, idGenerator, clock)));
        testNg.run();
    }

    /**
     * The setter for {@code configFailurePolicy} has a different signature depending on TestNG version.
     * This method uses reflection to detect the API and calls the version with the correct signature.
     *

            invalidPropertyNames.add(propertyName);
        } else {
            propDesc.setReadMethod(readMethod);
        }
    }

    /**
     * setterメソッドを準備します。
     *
     * @param writeMethod
     *            setterメソッド
     * @param propertyName
     *            プロパティ名
     */
    protected void setupWriteMethod(final Method writeMethod, final String propertyName) {

                if (accessorType != null) {
                    String propertyName = accessorType.propertyNameFor(name);
                    if (accessorType == PropertyAccessorType.IS_GETTER) {
                        booleanIsGetters.add(propertyName);
                    } else if (accessorType == PropertyAccessorType.GET_GETTER) {
                        booleanGetGetters.add(propertyName);

    KaSymbolWithKind {

    public abstract val hasGetter: Boolean
    public abstract val hasSetter: Boolean

    public abstract val getter: KaPropertyGetterSymbol?
    public abstract val setter: KaPropertySetterSymbol?
    public abstract val backingFieldSymbol: KaBackingFieldSymbol?

    public abstract val hasBackingField: Boolean

    public abstract val isDelegatedProperty: Boolean

        }

        then:
        publication.artifacts == [ivyArtifact] as Set
        publication.publishableArtifacts.files.files == [ivyDescriptorFile, artifactFile] as Set
    }

    def "can use setter to replace existing artifacts set on configuration"() {
        given:
        def publication = createPublication()
        def ivyArtifact1 = createArtifact()
        def ivyArtifact2 = createArtifact()

                    is KaConstructorSymbol -> "<constructor>"
                    is KaPropertyGetterSymbol -> callableId ?: "<getter>"
                    is KaPropertySetterSymbol -> callableId ?: "<setter>"
                    is KaAnonymousFunctionSymbol -> "<anonymous function>"
                    else -> error("unexpected symbol kind in KaCall: ${this@with::class}")
                }
            )
            append("(")