Apache Commons Lang 提供了一些构建方法（如 compareTo、equals、hashCode、和 toString）

PoliticalCandidate.java

import java.math.BigDecimal;
import java.util.Date;

import org.apache.commons.lang3.builder.CompareToBuilder;
import org.apache.commons.lang3.builder.ToStringBuilder;
import org.apache.commons.lang3.builder.ToStringStyle;

public class PoliticalCandidate implements Comparable<PoliticalCandidate> {

	private String lastName;
	private String firstName;
	private Date dateOfBirth;
	private BigDecimal moneyRaised;
	private State state;

	public PoliticalCandidate() {
	}

	public PoliticalCandidate(String lastName, String firstName, Date dateOfBirth, BigDecimal moneyRaised,
			State state) {
		this.lastName = lastName;
		this.firstName = firstName;
		this.dateOfBirth = dateOfBirth;
		this.moneyRaised = moneyRaised;
		this.state = state;
	}

	public String getLastName() {
		return lastName;
	}

	public void setLastName(String lastName) {
		this.lastName = lastName;
	}

	public String getFirstName() {
		return firstName;
	}

	public void setFirstName(String firstName) {
		this.firstName = firstName;
	}

	public Date getDateOfBirth() {
		return dateOfBirth;
	}

	public void setDateOfBirth(Date dateOfBirth) {
		this.dateOfBirth = dateOfBirth;
	}

	public BigDecimal getMoneyRaised() {
		return moneyRaised;
	}

	public void setMoneyRaised(BigDecimal moneyRaised) {
		this.moneyRaised = moneyRaised;
	}

	public State getState() {
		return state;
	}

	public void setState(State state) {
		this.state = state;
	}

	/*public String toString() {
		return ReflectionToStringBuilder.reflectionToString(this);
	}*/

	// get/set methods are omitted for brevity...
	@Override
	public String toString() {
		return new ToStringBuilder(this, ToStringStyle.DEFAULT_STYLE).append("lastName", lastName)
				.append("firstName", firstName).toString();
	}

	// get/set methods are omitted for brevity...
	/*public String toString() {
		return new ToStringBuilder(this, ToStringStyle.MULTI_LINE_STYLE).append("lastName", lastName)
				.append("firstName", firstName).toString();
	}*/

	// get/set methods are omitted for brevity...
	/*public String toString() {
		return new ToStringBuilder(this, ToStringStyle.NO_FIELD_NAMES_STYLE).append("lastName", lastName)
				.append("firstName", firstName).toString();
	}*/

	/*public String toString() {
		return new ToStringBuilder(this, ToStringStyle.SHORT_PREFIX_STYLE).append("lastName", lastName)
				.append("firstName", firstName).toString();
	}*/

	// get/set methods are omitted for brevity...
	/*public String toString() {
		return new ToStringBuilder(this, ToStringStyle.SIMPLE_STYLE).append("lastName", lastName)
				.append("firstName", firstName).toString();
	}*/

	/*public String toString() {
		return new ToStringBuilder(this, ToStringStyle.NO_CLASS_NAME_STYLE).append("lastName", lastName)
				.append("firstName", firstName).toString();
	}*/

	/*public String toString() {
		return new ToStringBuilder(this, ToStringStyle.JSON_STYLE).append("lastName", lastName)
				.append("firstName", firstName).toString();
	}*/

	/* (non-Javadoc)
	 * @see java.lang.Comparable#compareTo(java.lang.Object)
	 */
	//  A compare to which mimics the behavior of equals()
	/*public int compareTo(Object o) {
		int compare = -1; // By default return less-than
		if (o != null && PoliticalCandidate.class.isAssignableFrom(o.getClass())) {
			PoliticalCandidate pc = (PoliticalCandidate) o;
			compare = (new CompareToBuilder().append(firstName, pc.firstName).append(lastName, pc.lastName))
					.toComparison();
		}
		return compare;
	}*/

	@Override
	public int compareTo(PoliticalCandidate o) {
		return new CompareToBuilder().append(this.firstName, o.firstName).append(this.lastName, o.lastName)
				.toComparison();
	}
}

State.java

import org.apache.commons.lang3.builder.ReflectionToStringBuilder;

public class State {

	private String abbreviation;
	private String name;

	public State() {
	}

	public State(String abbreviation, String name) {
		this.abbreviation = abbreviation;
		this.name = name;
	}

	public String getAbbreviation() {
		return abbreviation;
	}

	public void setAbbreviation(String abbreviation) {
		this.abbreviation = abbreviation;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	@Override
	public String toString() {
		return ReflectionToStringBuilder.reflectionToString(this);
	}
}

ToStringExample.java

import java.math.BigDecimal;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;

public class ToStringExample {

	public static void main(String[] pArgs) throws Exception {
		// Create a State
		State va = new State("VA", "Virginia");

		// Create a Birth Date
		Calendar calendar = new GregorianCalendar();
		calendar.set(Calendar.YEAR, 1743);
		calendar.set(Calendar.MONTH, Calendar.APRIL);
		calendar.set(Calendar.DAY_OF_MONTH, 13);
		Date dob = calendar.getTime();

		BigDecimal moneyRaised = new BigDecimal(293829292.93);

		// Create a Political Candidate
		PoliticalCandidate candidate = new PoliticalCandidate("Jefferson", "Thomas", dob, moneyRaised, va);

		System.out.println(candidate);

		// Create a Political Candidate
		PoliticalCandidate candidate2 = new PoliticalCandidate("Jefferson", "Martha", null, null, null);

		// Create a Political Candidate
		PoliticalCandidate candidate3 = new PoliticalCandidate("Jefferson", "Martha", dob, null, va);

		System.out.println("Two Jeffersons are still different (should be > 0): " + candidate.compareTo(candidate2));
		System.out.println("Two Jeffersons are still different (should be < 0): " + candidate2.compareTo(candidate));
		System.out.println("Two Martha Js are the same (should be zero): " + candidate2.compareTo(candidate3));
	}
}