* Contrast the method above to:
 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},
 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)

)

// prepareUpdateMessage - prepares the update message, only if a
// newer version is available.
func prepareUpdateMessage(downloadURL string, older time.Duration) string {
	if downloadURL == "" || older <= 0 {
		return ""
	}

	// Compute friendly duration string to indicate time
	// difference between newer and current release.
	t := time.Time{}

    /**
     * Gets the identifier of this repository.
     *
     * @return the (case-sensitive) identifier, never {@code null}
     */
    @Nonnull
    String getId();

    /**
     * Gets the type of the repository, for example "default".
     *
     * @return the (case-sensitive) type of the repository, never {@code null}
     */
    @Nonnull
    String getType();

 * Contrast the method above to:
 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},
 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)

     * @param type The type of toolchain (e.g., "jdk", "compiler")
     * @param requirements Key-value pairs specifying toolchain requirements (e.g., "version": "11")
     * @return List of matching toolchains, never null
     * @throws ToolchainManagerException if toolchain retrieval fails
     */
    @Nonnull
    List<Toolchain> getToolchains(@Nonnull Session session, String type, Map<String, String> requirements);

    /**

 * Contrast the method above to:
 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},
 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)

 * Contrast the method above to:
 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},
 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)

 * Contrast the method above to:
 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},
 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)

 * Contrast the method above to:
 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},
 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)

    /**
     * Returns the local name of this XML node.
     *
     * @return the node name, never {@code null}
     */
    @Nonnull
    String name();

    /**
     * Returns the namespace URI of this XML node.
     *
     * @return the namespace URI, never {@code null} (empty string if no namespace)
     */
    @Nonnull
    String namespaceUri();

    /**