框架Hibernate Validator 简介

　　用Annotations 给类或者类的属性加上约束(constraint),在运行期检查属性值是很优雅的.Hibernate Validator就是这样的一个框架.该框架是十分轻易的(就像参考文档中宣称的那样),几乎没有什么学习曲线,Validator 是一个验证框架 不需要和Hibernate的其他部分绑定就可以使用,只要在你的项目中添加Hibernate-annotations.jar库就可以了.那么下面就让我们看看怎么使用吧.

Person.java 类
/*
* Created on 2006-1-12 Person.java
* @author
*/
package test.annotation.validator;

import org.hibernate.validator.Length;
import org.hibernate.validator.Min;
import org.hibernate.validator.Valid;
　

//@Serializability  //测试自定义约束
public class Person {

  PRivate String name;
  private int age;
  private Address address;
  
  public Person() {}
  
  @Valid //注重此处
  public Address getAddress() {
    return address;
  }
  public void setAddress(Address address) {
    this.address = address;
  }
  
  @Min(value = 1)
  public int getAge() {
    return age;
  }
  public void setAge(int age) {
    this.age = age;
  }
  
  @Length(min = 4)
  public String getName() {
    return name;
  }
  public void setName(String name) {
    this.name = name;
  }
}

Address.java 类

/*
* Created on 2006-1-12 Address.java
* @author
*/
package test.annotation.validator;

import org.hibernate.validator.Length;
import org.hibernate.validator.Max;
import org.hibernate.validator.Min;

public class Address {

  private String street;
  private int num;
  
  public Address() {}
  
  @Min(value = 1)
  @Max(value = 100)
  public int getNum() {
    return num;
  }
  public void setNum(int num) {
    this.num = num;
  }
  
  @Length(min = 3,max = 8)
  public String getStreet() {
    return street;
  }
  public void setStreet(String street) {
    this.street = street;
  }
}

　　上面是两个用 Validator Annotations 注释的 类. 每个属性都用 约束限制了.  下面看看测试的类吧:

TestValidator.java 类
/*
* Created on 2006-1-12
* @author icerain
*/
package test.annotation.validator;

import org.hibernate.validator.ClassValidator;
import org.hibernate.validator.InvalidValue;


public class TestValidator {
  public void test() {
    Address add = new Address();
    add.setNum(0);
    add.setStreet("1");
    
    Person p = new Person();
    p.setAddress(add);
    p.setAge(0);
    p.setName("ice");
    
    /******************Test validator ********/
    // 注重该处只验证了Person 为了说明 @Valid 注释的使用
    ClassValidator<Person> classValidator = new ClassValidator<Person> (Person.class);
    InvalidValue[] validMessages = classValidator.getInvalidValues(p);
    for (InvalidValue value : validMessages) {
      
    System.out.println("InvalidValue 的长度是:" + validMessages.length
        +" . 验证消息是: " + value.getMessage()
        + " . PropertyPath 是:" + value.getPropertyPath()
        +" ./n/t PropertyName 是: " +value.getPropertyName()
        + "Value 是: " + value.getValue()
        +" Bean 是: "+ value.getBean()
        +"/n/t BeanClass 是:" + value.getBeanClass());
    }
  }
  
  public static void main(String[] args) {
    new TestValidator().test();
  }
}