return localFile.writeTo(destination);
    }

    @Override
    @Nullable
    public ExternalResourceReadResult<Void> writeToIfPresent(File destination) throws ResourceException {
        return localFile.writeToIfPresent(destination);
    }

    @Override
    public ExternalResourceReadResult<Void> writeTo(OutputStream destination) throws ResourceException {

    public String toString() {
        return getDisplayName();
    }

    @Override
    public ExternalResourceReadResult<Void> writeTo(File destination) {
        ExternalResourceReadResult<Void> result = writeToIfPresent(destination);
        if (result == null) {
            throw ResourceExceptions.getMissing(getURI());
        }
        return result;
    }

    @Override

        def resource = new AccessorBackedExternalResource(name, resourceAccessor, resourceUploader, resourceLister, true)

        when:
        expectResourceRead(name, "12345")
        def result = resource.writeToIfPresent(file)

        then:
        result.bytesRead == 5
        file.text == "12345"
        0 * _

        when:
        expectResourceRead(name, "hi")
        result = resource.writeTo(file)

        def outFile = tmpDir.file("out")
        file.text = "1234"

        expect:
        def resource = new LocalFileStandInExternalResource(file, TestFiles.fileSystem())
        def result = resource.writeToIfPresent(outFile)
        result.bytesRead == 4
        outFile.text == "1234"

        file.setText("abc")
        def result2 = resource.writeTo(outFile)
        result2.bytesRead == 3

     *
     * @return null if this resource does not exist.
     * @throws ResourceException on failure to copy the content.
     */
    @Nullable
    ExternalResourceReadResult<Void> writeToIfPresent(File destination) throws ResourceException;

    /**
     * Copies the binary contents of this resource to the given stream. Does not close the provided stream.
     *

    }

    @Override
    public String getDisplayName() {
        return name.getDisplayName();
    }

    @Nullable
    @Override
    public ExternalResourceReadResult<Void> writeToIfPresent(File destination) throws ResourceException {
        return accessor.withContent(name, revalidate, inputStream -> {
            try (CountingInputStream input = new CountingInputStream(inputStream)) {

        } catch (IOException e) {
            throw ResourceExceptions.getFailed(getURI(), e);
        }
    }

    @Override
    @Nullable
    public ExternalResourceReadResult<Void> writeToIfPresent(File destination) {
        if (!localFile.exists()) {
            return null;
        }
        try {
            CountingInputStream input = new CountingInputStream(new FileInputStream(localFile));