static class MyTask extends DefaultTask {

        @Input
        String myProperty = "myValue"

        @InputFile
        @PathSensitive(PathSensitivity.NONE)
        File inputFile = new File("some-location")

        @InputFiles
        @PathSensitive(PathSensitivity.NONE)
        FileCollection inputFiles = TestFiles.fixed(new File("files"))

        @OutputFile
        File outputFile = new File("output")

import org.gradle.api.internal.AbstractBuildableComponentSpec;
import org.gradle.api.tasks.IgnoreEmptyDirectories;
import org.gradle.api.tasks.Input;
import org.gradle.api.tasks.InputFile;
import org.gradle.api.tasks.InputFiles;
import org.gradle.api.tasks.Internal;
import org.gradle.api.tasks.Optional;
import org.gradle.api.tasks.PathSensitive;
import org.gradle.api.tasks.PathSensitivity;

                @Optional
                @InputFile
                File inputFile

                @OutputFile
                File outputFile

                @TaskAction
                void doAction() {
                    if (inputFile != null) {
                        outputFile.text = inputFile.text
                    }
                }
            }

            import org.gradle.api.file.*
            import org.gradle.api.tasks.*

            class TaskWithTwoFileCollectionInputs extends DefaultTask {
                @InputFiles FileCollection inputs1
                @InputFiles FileCollection inputs2

                @OutputDirectory File output = project.buildDir

                @TaskAction void action() {}
            }
        """

                    def inputFiles = visitor.fileProperties*.propertyFiles*.files.flatten()
                    assert inputFiles.empty
                }
            }

            task customTask(type: CustomTask) {
                input = null
            }
        """

        expect:
        succeeds "customTask"

        where:
        annotation << [InputFile, InputDirectory, InputFiles]
    }

                    def inputFiles = parameters.nestedBean.inputFiles
                    def input = inputArtifact.get().asFile
                    println "processing \${input.name} using \${inputFiles*.name}"
                    def output = outputs.file(input.name + ".green")
                    def paramContent = inputFiles.collect { it.file ? it.text : it.list().length }.join("")

                void execute() {
                    def buildDirectory = projectLayout.buildDirectory
                    inputFiles.files.each { File inputFile ->
                        def outputFile = buildDirectory.file(inputFile.name + ".out").get().asFile
                        GFileUtils.copyFile(inputFile, outputFile)
                    }
                }
            }
            allprojects {

            error(missingNormalizationStrategyConfig { type('MyTask').property('inputFile').annotatedWith('InputFile') }, 'validation_problems', 'missing_normalization_annotation'),
            error(missingNormalizationStrategyConfig { type('MyTask').property('inputFiles').annotatedWith('InputFiles') }, 'validation_problems', 'missing_normalization_annotation'),
        ])

        and:

import org.gradle.api.model.ObjectFactory
import org.gradle.api.tasks.CacheableTask
import org.gradle.api.tasks.Classpath
import org.gradle.api.tasks.InputDirectory
import org.gradle.api.tasks.InputFile
import org.gradle.api.tasks.InputFiles
import org.gradle.api.tasks.OutputDirectory
import org.gradle.api.tasks.PathSensitive
import org.gradle.api.tasks.PathSensitivity
import org.gradle.api.tasks.SourceTask

                @InputFile
                Path inputFile
                @InputDirectory
                Path inputDir
                @OutputFile
                Path outputFile
                @OutputDirectory
                Path outputDir

                @TaskAction
                def go() {
                    outputFile.toFile().text = inputFile.toFile().text