public InstanceGroup withConfigurations(Configuration... configurations) {
        if (this.configurations == null) {
            setConfigurations(new com.amazonaws.internal.SdkInternalList<Configuration>(configurations.length));
        }
        for (Configuration ele : configurations) {
            this.configurations.add(ele);
        }
        return this;
    }
<note>
<p>
Amazon EMR releases 4.x or later.
</p>
</note>
<p>
The list of configurations supplied for an Amazon EMR cluster instance group. You can specify a separate
configuration for each instance group (master, core, and task).
</p>
<p>
<b>NOTE:</b> This method appends the values to the existing list (if any). Use
{@link #setConfigurations(java.util.Collection)} or {@link #withConfigurations(java.util.Collection)} if you want
to override the existing values.
</p>

@param configurations
       <p>
       Amazon EMR releases 4.x or later.
       </p>
       </note>
       <p>
       The list of configurations supplied for an Amazon EMR cluster instance group. You can specify a separate
       configuration for each instance group (master, core, and task).
@return Returns a reference to this object so that method calls can be chained together.
aws-java-sdk-emr/src/main/java/com/amazonaws/services/elasticmapreduce/model/InstanceGroup.java