一、Hibernate ValiDator介绍

Bean Validation是JSR303的定义，Hibernate Validator是对BeanValidation的实现，同时附加了几个自己的注解。

二、Hibernate Validator支持的注解

Bean Validation 中内置的 constraint  @Null   被注释的元素必须为 null
@NotNull    被注释的元素必须不为 null
@AssertTrue     被注释的元素必须为 true
@AssertFalse    被注释的元素必须为 false
@Min(value)     被注释的元素必须是一个数字，其值必须大于等于指定的最小值
@Max(value)     被注释的元素必须是一个数字，其值必须小于等于指定的最大值
@DecimalMin(value)  被注释的元素必须是一个数字，其值必须大于等于指定的最小值
@DecimalMax(value)  被注释的元素必须是一个数字，其值必须小于等于指定的最大值
@Size(max=, min=)   被注释的元素的大小必须在指定的范围内
@Digits (integer, fraction)     被注释的元素必须是一个数字，其值必须在可接受的范围内
@Past   被注释的元素必须是一个过去的日期
@Future     被注释的元素必须是一个将来的日期
@Pattern(regex=,flag=)  被注释的元素必须符合指定的正则表达式  Hibernate Validator 附加的 constraint
@NotBlank(message =)   验证字符串非null，且长度必须大于0
@Email  被注释的元素必须是电子邮箱地址
@Length(min=,max=)  被注释的字符串的大小必须在指定的范围内
@NotEmpty   被注释的字符串的必须非空
@Range(min=,max=,message=)  被注释的元素必须在合适的范围内  

三、代码演示

1.pom文件

   <dependency><groupId>javax.el</groupId><artifactId>javax.el-api</artifactId><version>2.2.4</version></dependency><dependency><groupId>org.glassfish.web</groupId><artifactId>javax.el</artifactId><version>2.2.4</version></dependency>

2.Bean

public class Student {interface GroupA {}interface GroupB {}interface GroupC {}@NotNull(message = "姓名不能为空", groups = GroupA.class)private String name;private int age;@Range(min = 1, max = 2, groups = GroupB.class)private Double money;@Size(min = 1, max = 3)private String address;@Size(min = 1, max = 2, groups = GroupC.class)private List<String> registerClass;@Email(groups = GroupB.class)private String email;

3.验证代码

 public static void main(String[] args) {Student student = new Student();//student.setName("Tom");student.setAddress("浙江省杭州市");student.setAge(101);student.setMoney(101D);student.setEmail("as");student.setRegisterClass(Lists.newArrayList("Englist","Math","haha"));ValidatorFactory factory = Validation.buildDefaultValidatorFactory();Validator validator = factory.getValidator();Set<ConstraintViolation<Student>> constraintViolationSet =  validator.validate(student, GroupA.class,GroupB.class);for (ConstraintViolation<Student> constraintViolation : constraintViolationSet) {System.out.println(constraintViolation.getPropertyPath() + constraintViolation.getMessage());}}

除了支持基本已经实现的验证功能之外，还支持分组，针对不同组进行验证。

四、Bean Validator的扩展

下面实现一个Validator，目的是检测一个List里面的所有元素在一定的范围，如果超过一定的范围或者不是Number类型的就返回提示

1.定义一个validator注解

@Constraint(validatedBy = CheckListRangeValidator.class)
@Target({ElementType.FIELD, ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface CheckListRange {String message() default "{List里面的元素必须大于min 小于max}";int min() default Integer.MIN_VALUE;int max() default Integer.MAX_VALUE;Class<?>[] groups() default {};Class<? extends Payload>[] payload() default {};
}

2.validator的实现

public class CheckListRangeValidator implements ConstraintValidator<CheckListRange, List> {private int min;private int max;public void initialize(CheckListRange constraintAnnotation) {this.min = constraintAnnotation.min();this.max = constraintAnnotation.max();}public boolean isValid(List value, ConstraintValidatorContext context) {for (Object object : value) {if (object == null || !(object instanceof Number)) {return false;}if (((Number)object).doubleValue() < min || ((Number)object).doubleValue() > max) {return false;}return true;}return false;}}

3.Bean里面使用自定义validator注解

public class Student {interface GroupA {}interface GroupB {}interface GroupC {}@NotNull(message = "姓名不能为空", groups = GroupC.class)private String name;private int age;@Range(min = 1, max = 2, groups = GroupB.class)private Double money;@Size(min = 1, max = 3)private String address;@Size(min = 1, max = 2, groups = GroupC.class)private List<String> registerClass;@Email(groups = GroupB.class)private String email;@CheckListRange(min = 1, max = 100, message = "List中元素必须在大于等于1,小于等于100", groups = GroupC.class)//当使用自定义注解的时候一定要加上@Valid不然不会被识别@Valid  private List<? extends  Number> scoreList;}

4.检测代码

public class MainTest {public static void main(String[] args) {Student student = new Student();//student.setName("Tom");student.setAddress("浙江省杭州市");student.setAge(101);student.setMoney(101D);student.setEmail("as");student.setRegisterClass(Lists.newArrayList("Englist","Math","haha"));student.setScoreList(Lists.newArrayList(-1.1D,3D,3D,3D));ValidatorFactory factory = Validation.buildDefaultValidatorFactory();Validator validator = factory.getValidator();Set<ConstraintViolation<Student>> constraintViolationSet =  validator.validate(student, GroupC.class);for (ConstraintViolation<Student> constraintViolation : constraintViolationSet) {System.out.println(constraintViolation.getPropertyPath() + constraintViolation.getMessage());}}
}

5.最后结果

四月 01, 2017 2:36:54 下午 org.hibernate.validator.internal.util.Version <clinit>
INFO: HV000001: Hibernate Validator 5.3.4.Final
name姓名不能为空
scoreListList中元素必须在大于等于1,小于等于100
registerClass个数必须在1和2之间Process finished with exit code 0

五、Spring MVC中的使用

/*** 备注：此处@Validated(PersonAddView.class) 表示使用PersonAndView这套校验规则，若使用@Valid 则表示使用默认校验规则，@RequestMapping(value = "/student", method = RequestMethod.POST)public void addStudent(@RequestBody @Validated({GroupC.class}) Student student) {System.out.println(student.toString());}/*** 修改Person对象* 此处启用PersonModifyView 这个验证规则*/@RequestMapping(value = "/student", method = RequestMethod.PUT)public void modifyStudent(@RequestBody @Validated(value = {GroupA.class}) Student student) {           System.out.println(student.toString());}