Commons Lang、StandardToStringStyle#setFieldNameValueSeparator

import org.apache.commons.lang.builder.StandardToStringStyle;

public class C2009080200 {
    public static void main(String[] args) {
        StandardToStringStyle x = new StandardToStringStyle();
        System.out.println(x.getFieldNameValueSeparator());

        x.setFieldNameValueSeparator(":");
        System.out.println(x.getFieldNameValueSeparator());
    }
}

で、

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