rest-assured/src/main/java/io/restassured/config/MultiPartConfig.java
public MultiPartConfig defaultControlName(String defaultControlName) {
        return new MultiPartConfig(defaultControlName, defaultFileName, defaultSubtype, defaultBoundary, defaultCharset, true);
    }
public MultiPartConfig defaultControlName(String defaultControlName) {
        return new MultiPartConfig(defaultControlName, defaultFileName, defaultSubtype, defaultBoundary, defaultCharset, true);
    }
Specify the default control name to use if not defined explicitly in multi-part request.
<p>
Default is {@value #DEFAULT_CONTROL_NAME}
</p>

@param defaultControlName The control name to use
@return A new instance of {@link MultiPartConfig}