例子参考自官方文档，http://oval.sourceforge.net/u...
官方文档的xml配置有点过期了，一两个属性不合法。

├─src
│  ├─main
│  │  ├─java
│  │  │  └─com
│  │  │      └─honey
│  │  │          ├─collection
│  │  │          └─oval
│  │  └─resources

Userbean类，

package com.honey.oval;

public class User {
    private String firstName;
    private String lastName;
    private String managerId;
    private String userId;

    public User() {

    }
    public User(String firstName,String lastName) {
        this.firstName = firstName;
        this.lastName = lastName;
    }

    public void setPasswordExpirationDays(int days) {

    }

}

OvalAppTest测试类，

package com.honey;

import com.honey.oval.User;
import net.sf.oval.ConstraintViolation;
import net.sf.oval.configuration.xml.XMLConfigurer;
import net.sf.oval.guard.Guard;

import java.util.List;


public class OvalAppTest {

    public static void main(String[] args) {
        User user = new User("honey","wang");
        XMLConfigurer xmlConfigurer = new XMLConfigurer(ClassLoader.class.getResourceAsStream("/oval-config.xml"));

        Guard guard = new Guard(xmlConfigurer);
        List<ConstraintViolation> constraintViolationList = guard.validate(user);
        System.out.println(constraintViolationList);
    }
}

xml配置，src/resources/oval-config.xml

<?xml version="1.0" ?>
<oval
        xmlns="http://oval.sf.net/oval-configuration"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://oval.sf.net/oval-configuration http://oval.sourceforge.net/oval-configuration.xsd"
>
    <!-- define a constraint set -->
    <constraintSet id="user.userid">
        <notNull />
        <matchPattern matchAll="false">
            <pattern pattern="^[a-z0-9]{8}$" flags="0" />
        </matchPattern>
    </constraintSet>

    <!-- define checks for the acme.model.User class -->
    <!-- overwrite=false means already defined checks for this class will not be removed -->
    <class type="com.honey.oval.User" overwrite="false" applyFieldConstraintsToSetters="true">

        <field name="firstName">
            <length min="0" max="3" />
        </field>

        <field name="lastName">
            <length min="0" max="5" />
        </field>

        <!-- overwrite=true means prevIoUsly defined checks for this field will be overwritten by the checks defined here -->
        <field name="managerId" overwrite="true">
            <!-- use the checks defined for the constaint set "user.userid" -->
            <assertConstraintSet id="user.userid" />
        </field>

        <field name="userId" overwrite="true">
            <!-- use the checks defined for the constaint set "user.userid" -->
            <assertConstraintSet id="user.userid" />
        </field>

        <!-- define constructor parameter checks -->
        <constructor>
            <!-- parameter1 -->
            <parameter type="java.lang.String">
                <notNull />
            </parameter>

            <!-- parameter 2 -->
            <!-- the types of all parameters must be listed,even if no checks are defined -->
            <parameter type="java.lang.String" />
        </constructor>

        <!-- define method parameter checks -->
        <method name="setPasswordExpirationDays">
            <!-- parameter 1 -->
            <parameter type="int">
                <notNull />
            </parameter>
        </method>
    </class>
</oval>

输出结果，

[net.sf.oval.ConstraintViolation: com.honey.oval.User.managerId cannot be null,net.sf.oval.ConstraintViolation: com.honey.oval.User.firstName is not between 0 and 3 characters long,net.sf.oval.ConstraintViolation: com.honey.oval.User.userId cannot be null]