就和宣告查詢參數時一樣，當模型屬性有預設值時，它就不是必填；否則就是必填。使用 `None` 可使其成為選填。

例如，上述模型對應的 JSON「`object`」（或 Python `dict`）如下：

```JSON
{
    "name": "Foo",
    "description": "An optional description",
    "price": 45.2,
    "tax": 3.5
}
```

...由於 `description` 與 `tax` 是選填（預設為 `None`），以下這個 JSON「`object`」也有效：

```JSON
{
    "name": "Foo",
    "price": 45.2
}
```

## 將它宣告為參數 { #declare-it-as-a-parameter }

    }

    @Test
    void testToString() {
        String result = setupAndX.toString();
        assertNotNull(result);
        assertTrue(result.contains("SmbComSessionSetupAndX"), "toString should contain class name");
    }

    public void execute(MavenSession session) {}

    @Override
    public Set<Plugin> getPluginsBoundByDefaultToAllLifecycles(String packaging) {
        Set<Plugin> plugins;

        // NOTE: The upper-case packaging name is intentional, that's a special hinting mode used for certain tests
        if ("JAR".equals(packaging)) {
            plugins = new LinkedHashSet<>();

        StringBuilder msg = new StringBuilder(message);
        problems.problems().forEach(problem -> msg.append("\n * ")
                .append(problem.getSeverity().name())
                .append(": ")
                .append(problem.getMessage()));
        return msg.toString();
    }

    /**
     * Returns the problem collector associated with this exception.
     *

     */
    @Override
    public void setThreshold(int threshold) {}

    /**
     * <b>Warning</b>: ignored (always return <code>null</code>).
     */
    @Override
    public Logger getChildLogger(String name) {
        return null;
    }

    @Override
    public String getName() {
        return logger.getName();
    }

    private void setMdc() {

			--upload-id "$uploadId" --bucket bucket --key obj-1 \
			--part-number "$i" --body ./file-5mib
	done
	for i in {1..6}; do
		find ${WORK_DIR}/disk${i}/.minio.sys/multipart/ -type f -name "part.1" -delete
	done
	cat <<EOF >parts.json
{
    "Parts": [
        {
            "PartNumber": 1,
            "ETag": "5f363e0e58a95f06cbe9bbc662c5dfb6"
        },
        {

	for tier, st := range m {
		l[tier] = l[tier].merge(st)
	}
}

func (l DailyAllTierStats) addToTierInfo(tierInfos []madmin.TierInfo) []madmin.TierInfo {
	for i := range tierInfos {
		lst, ok := l[tierInfos[i].Name]
		if !ok {
			continue
		}
		for hr, st := range lst.Bins {
			tierInfos[i].DailyStats.Bins[hr] = madmin.TierStats{
				TotalSize:   st.TotalSize,
				NumVersions: st.NumVersions,

        final int outputLevel = logger.isDebugEnabled() ? Project.MSG_DEBUG : Project.MSG_INFO
        final PrintStream stream = useStdout() ? System.out : new PrintStream(outputBuffer, true, Charset.defaultCharset().name())
        BuildLogger antLogger = makeLogger(stream, outputLevel)

        ant.project.addBuildListener(antLogger)
        try {
            runAnt(ant)
        } catch (Exception e) {

  val subjectPublicKeyInfo: SubjectPublicKeyInfo,
  val issuerUniqueID: BitString?,
  val subjectUniqueID: BitString?,
  val extensions: List<Extension>,
) {
  /**
   * Returns the standard name of this certificate's signature algorithm as specified by
   * [Signature.getInstance]. Typical values are like "SHA256WithRSA".
   */
  val signatureAlgorithmName: String
    get() {

     * @param fileAttributes The attributes of the mock file.
     * @param expectedResult The expected outcome of the accept method.
     * @throws SmbException If an SMB error occurs.
     */
    @ParameterizedTest(name = "Filter: {0}, File: {1}, Expected: {2}")
    @CsvSource({
            // Positive cases (should be accepted)
            "1, 1, true", // ATTR_READONLY
            "2, 2, true", // ATTR_HIDDEN