用Guava简化equals，hashCode和toString的编写。

JavaBeanEqualsByGuava.java

@Override
public boolean equals(Object o) {
    if (this == o) return true;
    if (o == null || getClass() != o.getClass()) return false;

    UpdateConfig that = (UpdateConfig) o;

    return  Objects.equal(fromVersion, that.fromVersion)
            && Objects.equal(targetVersion, that.targetVersion);
}

@Override
public int hashCode() {
    return Objects.hashCode(fromVersion, targetVersion);
}


@Override
public String toString() {
    return Objects.toStringHelper(this)
            .add("id", id)
            .add("fromVersion", fromVersion)
            .add("targetVersion", targetVersion)
            .add("versionType", versionType)
            .add("desc", desc)
            .toString();
}