protected void setContentStart(String contentStart) {
        if (contentStart == null) {
            contentStart = "";
        }
        this.contentStart = contentStart;
    }
<p>Sets the content start text.</p>

<p><code>null</code> is accepted, but will be converted to
an empty String.</p>

@param contentStart  the new content start text
android/android_framework/base/src/main/java/lang3/builder/ToStringStyle.java