GuardMan

GuardMan ("Guard man" in Japanese means "Security guard") is a simple validation library for Java.

import static security.CredentialDtoMeta.*;

public class CredentialDtoValidator  {

    public Violations validate(CredentialDto bean) {
        BeanValidationContext<CredentialDto> context = new BeanValidationContext<>(bean);
        context.property(userCode).required().validate(
            minLength(0),
            maxLength(10),
            alphaNumeric(false)
        );
        context.property(password).required().validate(PasswordValidator.INSTANCE);
        context.property(version).required().eq(ApplicationDescriptor.getVersion());
        return context;
    }

}

Installation

1. Add Maven repository: http://monzou.github.com/maven-repository/
2. Add dependency: com.github.monzou:guardman:${version}

Configuration example for Gradle:

repositories {
    maven {
        url "http://monzou.github.com/maven-repository/"
    }
}
dependencies {
    compile "com.github.monzou:guardman:${version}"
}

How to use

Validate with grinder (Recommended due to maintenance and performance).

BeanValidationContext<Trade> context = new BeanValidationContext<>(bean);
context.property(TradeMeta.tradeNo).required().validate(
  minLength(0),
  maxLength(10),
  alphaNumeric(false)
);
context.property(TradeMeta.remarks).validate(maxLength(1000));
for (CashFlow cashFlow : context.property(TradeMeta.cashFlows).required().validate(notEmpty()).getValue()) {
    BeanValidationContext<CashFlow> c = new BeanValidationContext<>(String.format("CashFlow %d", cashFlow.getSeqNo()), cashFlow);
    c.property(CashFlowMeta.seqNo).required().validate(max(100));
    c.property(CashFlowMeta.amount).required().validate(
      min(BigDecimal.ZERO),
      max(new BigDecimal("100000000"))
    );
    c.property(CashFlowMeta.startDate).required().lt(CashFlowMeta.endDate);
    c.property(CashFlowMeta.endDate).required();
    context.addViolations("cashFlows", c);
}
for (Violation violation : context) {
    System.out.println(violation.getKey());
    System.out.println(violation.getSeverity());
    System.out.println(violation.getMessage());
}

Or, you can use reflection for property access like this:

BeanValidationContext<Trade> context = new BeanValidationContext<>(bean);
context.<String> property("tradeNo").required().validate(
  minLength(0),
  maxLength(10),
  alphaNumeric(false)
);
context.<String> property("remarks").validate(maxLength(1000));
for (CashFlow cashFlow : context.<List<CashFlow>> property("cashFlows").required().validate(notEmpty()).getValue()) {
    BeanValidationContext<CashFlow> c = new BeanValidationContext<>(String.format("CashFlow %d", cashFlow.getSeqNo()), cashFlow);
    c.<Integer> property("seqNo").required().validate(max(100));
    c.<BigDecimal> property("amount").required().validate(
      min(BigDecimal.ZERO),
      max(new BigDecimal("100000000"))
    );
    c.<Date> property("startDate").required().lt(cashFlow.getEndDate());
    c.<Date> property("endDate").required();
    context.addViolations("cashFlows", c);
}
for (Violation violation : context) {
    System.out.println(violation.getKey());
    System.out.println(violation.getSeverity());
    System.out.println(violation.getMessage());
}

Custom Validator

If you want to use custom validator, just implement ValueValidator.

For example:

public class NonZeroValidator extends AbstractMutableValueValidator<Number> {

    /** {@inheritDoc} */
    @Override
    public boolean apply(Number value) {
        return value == null ? true : toBigDecimal(value).compareTo(BigDecimal.ZERO) != 0;
    }

    /** {@inheritDoc} */
    @Override
    protected String resolveMessage(Number value, Object... params) {
        return Messages.get(getClass().getSimpleName());
    }

}

Configuration

i18n

Configure com.github.monzou.guardman.i18n.LocaleProvider for translating validation messages. If you want to customize validation messages, just put guardman.properties into your classpath. For example:

• guardman.properties (fallback bundle)
• guardman_en.properties
• guardman_ja.properties

NOTE: Please use UTF-8 encoding for each properties file. You don't have to use native2ascii.

Requirements

• JDK 7 +

Dependencies

• Grinder
• Google Guava

License

(The MIT License)

Copyright (c) 2014 Takuro Monji @monzou