Adição de validador agência bancária (#301)

* Adicao de validador de agencia bancaria

* Remocao do uso de Objects disponivel a partir do Java 7

stella-core/src/main/java/br/com/caelum/stella/validation/AgenciaBancariaValidator.java

@@ -0,0 +1,110 @@
+package br.com.caelum.stella.validation;
+
+import br.com.caelum.stella.DigitoGenerator;
+import br.com.caelum.stella.MessageProducer;
+import br.com.caelum.stella.SimpleMessageProducer;
+import br.com.caelum.stella.ValidationMessage;
+import br.com.caelum.stella.validation.error.AgenciaBancariaError;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+/**
+ * Representa um validador de agencia bancária.
+ * 
+ * @author Thiago Nascimento
+ */
+public class AgenciaBancariaValidator implements Validator<String> {
+
+	public static final Pattern COM_DV = Pattern.compile("(\\d+)\\-([\\dX])");
+    public static final Pattern SEM_DV = Pattern.compile("\\d+");
+
+    private boolean isComDigito = true;
+    private MessageProducer messageProducer;
+
+    public AgenciaBancariaValidator() {
+    	this.messageProducer = new SimpleMessageProducer();
+	}
+
+	public AgenciaBancariaValidator(boolean isComDigito) {
+		this();
+		this.isComDigito = isComDigito;
+	}
+
+	@Override
+	public void assertValid(String agencia) {
+
+		List<ValidationMessage> errors = this.invalidMessagesFor(agencia);
+
+		if (!errors.isEmpty()) {
+			throw new InvalidStateException(errors);
+	    }
+	}
+
+	@Override
+	public List<ValidationMessage> invalidMessagesFor(String agencia) {
+
+		List<ValidationMessage> errors = new ArrayList<ValidationMessage>();
+
+		if (this.isEligible(agencia)) {
+
+			if (this.isComDigito) {
+
+				Matcher matcher = COM_DV.matcher(agencia);
+
+				if (!matcher.find()) {
+					throw new InvalidStateException(this.messageProducer.getMessage(AgenciaBancariaError.INVALID_FORMAT));
+				}
+
+				String dvInformado = matcher.group(2);
+				String dvComputado = this.computarDigitoVerificador(matcher.group(1));
+
+				if (!dvInformado.equals(dvComputado)) {
+					errors.add(this.messageProducer.getMessage(AgenciaBancariaError.INVALID_CHECK_DIGIT));	
+				}
+
+			} else {
+				errors.add(this.messageProducer.getMessage(AgenciaBancariaError.CHECK_DIGIT_NOT_FOUND));
+			}
+
+		} else {
+			errors.add(this.messageProducer.getMessage(AgenciaBancariaError.INVALID_FORMAT));
+		}
+
+		return errors;
+	}
+
+	@Override
+	public boolean isEligible(String value) {
+
+		if (value == null || value.trim().isEmpty()) {
+			return false;
+		}
+
+		return this.isComDigito ? 
+				COM_DV.matcher(value).matches() : SEM_DV.matcher(value).matches();
+	}
+
+	@Override
+	public String generateRandomValid() {
+		final String agenciaSemDigitos = new DigitoGenerator().generate(4);
+		return String.format("%s-%s", agenciaSemDigitos, this.computarDigitoVerificador(agenciaSemDigitos));
+	}
+
+	public String computarDigitoVerificador(String agenciaSemDV) {
+
+		String[] algarisms = agenciaSemDV.split(""); 
+		int multiplier = 9;
+		int sum = 0;
+
+		for (int index = algarisms.length - 1; index >= 0; --index) {
+			sum += Integer.valueOf(algarisms[index]) * multiplier--;
+		}
+
+		int rest = sum % 11;
+		return rest == 10 ? "X" : String.valueOf(rest); 
+	}
+
+}

stella-core/src/main/java/br/com/caelum/stella/validation/error/AgenciaBancariaError.java

@@ -0,0 +1,7 @@
+package br.com.caelum.stella.validation.error;
+
+import br.com.caelum.stella.validation.InvalidValue;
+
+public enum AgenciaBancariaError implements InvalidValue {
+	INVALID_CHECK_DIGIT, CHECK_DIGIT_NOT_FOUND, INVALID_FORMAT
+}

stella-core/src/test/java/br/com/caelum/stella/validation/AgenciaBancariaValidatorTest.java

@@ -0,0 +1,70 @@
+package br.com.caelum.stella.validation;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
+import org.junit.Test;
+
+import br.com.caelum.stella.MessageProducer;
+import br.com.caelum.stella.SimpleMessageProducer;
+import br.com.caelum.stella.validation.error.AgenciaBancariaError;
+
+/**
+ * @author Thiago Nascimento
+ */
+public class AgenciaBancariaValidatorTest {
+
+	private MessageProducer messageProducer = new SimpleMessageProducer();
+
+	@Test
+	public void shouldAcceptEligibleAgenciasComDV() {
+		AgenciaBancariaValidator validator = new AgenciaBancariaValidator();
+		assertTrue(validator.isEligible("3610-2"));
+		assertFalse(validator.isEligible("3610"));
+	}
+
+	@Test
+	public void shouldAcceptEligibleAgenciasSemDV() {
+		AgenciaBancariaValidator validator = new AgenciaBancariaValidator(false);
+		assertFalse(validator.isEligible("3610-2"));
+		assertTrue(validator.isEligible("3610"));
+	}
+
+	@Test
+	public void shouldReturnNoValidationMessagesForCorrectAgenciasComDV() {
+		AgenciaBancariaValidator validator = new AgenciaBancariaValidator();
+		assertTrue(validator.invalidMessagesFor("3610-2").isEmpty());
+		assertTrue(validator.invalidMessagesFor("3793-1").isEmpty());
+		assertTrue(validator.invalidMessagesFor("197-X").isEmpty());
+		assertTrue(validator.invalidMessagesFor("4158-0").isEmpty());
+		assertTrue(validator.invalidMessagesFor("2121-0").isEmpty());
+		assertTrue(validator.invalidMessagesFor("1284-X").isEmpty());
+	}
+
+	@Test
+	public void shouldReturnInvalidCheckDigitForIncorrectDV() {
+
+		AgenciaBancariaValidator validator = new AgenciaBancariaValidator();
+
+		try {
+			validator.assertValid("2121-9");
+			fail();
+		} catch (InvalidStateException e) {
+			e.getInvalidMessages().contains(this.messageProducer.getMessage(AgenciaBancariaError.INVALID_CHECK_DIGIT));
+		}
+	}
+
+	@Test
+	public void shouldReturnCheckDigitNotFoundForAgenciaSemDV() {
+
+		AgenciaBancariaValidator validator = new AgenciaBancariaValidator();
+
+		try {
+			validator.assertValid("1103");
+			fail();
+		} catch (InvalidStateException e) {
+			e.getInvalidMessages().contains(this.messageProducer.getMessage(AgenciaBancariaError.CHECK_DIGIT_NOT_FOUND));
+		}
+	}
+}