package <%=packageName%>.config;

/**
 * Application constants.
 */
public interface Constants {

    public static final String SPRING_PROFILE_DEVELOPMENT = "dev";
    public static final String SPRING_PROFILE_PRODUCTION = "prod";
    public static final String SYSTEM_ACCOUNT = "system";

}

package <%=packageName%>.config;

/**
 * Application constants.
 */
public final class Constants {

    private Constants() {
    }

    public static final String SPRING_PROFILE_DEVELOPMENT = "dev";
    public static final String SPRING_PROFILE_PRODUCTION = "prod";
    public static final String SYSTEM_ACCOUNT = "system";

}

Use a final class with private constructor instead of interface