*
     * @return the plugin id in the form {@code <groupId>:<artifactId>:<version>}, never {@code null}
     */
    public String getId() {
        return new StringBuilder(128)
            .append((getGroupId() == null) ? "[unknown-group-id]" : getGroupId())
            .append(":")
            .append((getArtifactId() == null) ? "[unknown-artifact-id]" : getArtifactId())
            .append(":")

      <codeSegments>
        <codeSegment>
          <version>1.0.0+</version>
          <code>
            <![CDATA[

    public String toString() {
        StringBuilder sb = new StringBuilder(128);
        sb.append("Mirror[");
        sb.append("id=").append(this.getId());
        sb.append(",mirrorOf=").append(this.getMirrorOf());
        sb.append(",url=").append(this.getUrl());