Commons Lang、StandardToStringStyle#setUseIdentityHashCode

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

public class C2009081300 {
    public static void main(String[] args) {
        StandardToStringStyle x = new StandardToStringStyle();
        System.out.println(x.isUseIdentityHashCode());

        x.setUseIdentityHashCode(false);
        System.out.println(x.isUseIdentityHashCode());
    }
}

で、

true
false