conventionMappingOf(extension).map("targetJdk", () ->
            getDefaultTargetJdk(getJavaPluginExtension().getSourceCompatibility()));
        return extension;
    }

    public TargetJdk getDefaultTargetJdk(JavaVersion javaVersion) {
        try {
            return TargetJdk.toVersion(javaVersion.toString());
        } catch (IllegalArgumentException ignored) {

        1.3                 | TargetJdk.VERSION_1_3
        1.4                 | TargetJdk.VERSION_1_4
        1.5                 | TargetJdk.VERSION_1_5
        1.6                 | TargetJdk.VERSION_1_6
        1.7                 | TargetJdk.VERSION_1_7
        // 1.4 is the default in the pmd plugin so we use it as a default too
        1.8                 | TargetJdk.VERSION_1_4
        1.1                 | TargetJdk.VERSION_1_4

    }

    /**
     * The target JDK to use with PMD.
     */
    @Input
    public TargetJdk getTargetJdk() {
        return targetJdk;
    }

    /**
     * The target JDK to use with PMD.
     */
    public void setTargetJdk(TargetJdk targetJdk) {
        this.targetJdk = targetJdk;
    }

    /**

        }
        if (withJavaExtension != null) {
            configureJavaPluginToolchainVersion(selectJdk(withJavaExtension))
        }

        def targetJdk = selectJdk(target)
        def groovyTarget = GroovyCoverage.getEffectiveTarget(versionNumber, targetJdk.javaVersion)

        when:
        withInstallations(currentJdk, otherJdk).run(":compileGroovy", "--info")

        then:

        }

        def targetJdk = selectJdk(target)

        when:
        withInstallations(currentJdk, otherJdk).run(":compileJava", "--info")

        then:
        executedAndNotSkipped(":compileJava")
        outputContains("Compiling with toolchain '${targetJdk.javaHome.absolutePath}'")
        classJavaVersion(javaClassFile("Foo.class")) == targetJdk.javaVersion

        where:

        }

        def targetJdk = selectJdk(target)

        when:
        withInstallations(currentJdk, otherJdk).run(":compileScala", "--info")

        then:
        executedAndNotSkipped(":compileScala")
        outputContains("Compiling with Zinc Scala compiler")

        JavaVersion.forClass(scalaClassFile("JavaThing.class").bytes) == targetJdk.javaVersion

            testing.suites.test.useJUnit()

            pmd {
                toolVersion = '$version'
                // Set target JDK for PMD <5.x tests, so the test code is accepted
                targetJdk = TargetJdk.VERSION_1_7
                ${supportIncrementalAnalysis() ? "" : "incrementalAnalysis = false"}
            }

            ${fileLockingIssuesSolved() ? "" : """
            tasks.withType(Pmd) {

            }

            def requestedGradleVersion = project.findProperty("gradleVersion")
            def requestedTargetJdk = project.findProperty("targetJdk")

            // Earlier versions of Gradle can sometimes fail to connect to the just started Gradle daemon.
            // The failure will be the "tried to connect to 100 daemons" error