gistfile1.java

@Retention(value=RetentionPolicy.RUNTIME)
@Target(value=ElementType.FIELD)
public @interface CipherKey {

}

gistfile2.java

@Retention(value=RetentionPolicy.RUNTIME)
@Target(value=ElementType.FIELD)
public @interface CipherData {

}

gistfile3.java

public class CipherEntityListener {
	
	@PrePersist @PreUpdate
	@SuppressWarnings("unchecked")
	public void cipherEntityUsingMD5(Object entity) throws Exception {
		CipherHelper cipherHelper = null;
		String privateKey = null;
		String recordData = null;
		StringBuffer sb = null;
		Class classType = null;
		Field[] fieldList = null;
		Object fieldValue = null;
		String sValue = null;
		boolean keyHasBeenSet = false;
		boolean dataHasBeenSet = false;
		try {
			sb = new StringBuffer();
			classType = entity.getClass();
			fieldList = classType.getDeclaredFields();
			for (Field field : fieldList) {
				field.setAccessible(true);
				fieldValue = field.get(entity);
				if (fieldValue != null) {
					sValue = fieldValue.toString();
					sb.append(sValue);
				}
			}
			cipherHelper = CipherHelper.getInstance();
			privateKey = cipherHelper.generatePrivateKey();
			recordData = cipherHelper.encryptDataUsingMD5(sb.toString(),
					privateKey);
			for (Field field : fieldList) {
				if (field.isAnnotationPresent(CipherKey.class)) {
					field.set(entity, privateKey);
					keyHasBeenSet = true;
				}
				if (field.isAnnotationPresent(CipherData.class)) {
					field.set(entity, recordData);
					dataHasBeenSet = true;
				}
				if (keyHasBeenSet && dataHasBeenSet) {
					break;
				}
			}
		} catch (Exception ex) {
			throw ex;
		}
	}

}

gistfile4.java

@Entity
@Table(name="tab_cliente")
@SuppressWarnings("serial")
@EntityListeners(CipherEntityListener.class)
public class Cliente implements Serializable {
	
	@Id
	@Column(name="cod_cliente")
	@GeneratedValue(strategy=GenerationType.IDENTITY)
	private int codigo;

	@Column(name="nome_cliente", length=100)
	private String nome;
	
	@Column(name="cpf_cliente", length=20)
	private String cpf;
	
	@Column(name="data_nasc")
	@Temporal(TemporalType.DATE)
	private Date dataNascimento;
	
	@CipherKey
	private String privateKey;
	
	@CipherData
	private String recordData;
	
	private boolean casado;

}