java使用validator进行校验
不管是html页面表单提交的对象数据还是和第三方公司进行接口对接,都需要对接收到的数据进行校验(非空、长度、格式等等)。如果使用if一个个进行校验(字段非常多),这是让人崩溃的过程。幸好jdk或hibernate都提供了对object对象的校验,只需加上相应的注解即可。
是用来练手的
ValidatorUtil.java
ValidatorTest.java
来看看运行结果:
看到运行结果,心中一喜,达到了我们的要求。
MoneyValidator.java
StudentInfo.java
ValidatorTest.java
运行结果:
当然,如果你的项目使用springMVC或structs2,都会对应的集成方法。
StudentInfo.java
ValidatorTest.java
运行结果:
转自:https://blog.****.net/dream_broken/article/details/53584169
本人喜欢学习时,都建立个maven小项目进行实践学习。
1.项目建立
pom.xml
- <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
- <modelVersion>4.0.0</modelVersion>
- <groupId>com.fei</groupId>
- <artifactId>validation-test</artifactId>
- <version>0.0.1-SNAPSHOT</version>
- <dependencies>
- <dependency>
- <groupId>javax.el</groupId>
- <artifactId>javax.el-api</artifactId>
- <version>2.2.4</version>
- </dependency>
- <dependency>
- <groupId>org.hibernate</groupId>
- <artifactId>hibernate-validator</artifactId>
- <version>5.1.3.Final</version>
- </dependency>
- </dependencies>
- </project>
2.基本校验练习
StudentInfo.java
- package com.fei.info;
- import javax.validation.constraints.Pattern;
- import org.hibernate.validator.constraints.NotBlank;
- public class StudentInfo {
- @NotBlank(message="用户名不能为空")
- private String userName;
- @NotBlank(message="年龄不能为空")
- @Pattern(regexp="^[0-9]{1,2}$",message="年龄是整数")
- private String age;
- /**
- * 如果是空,则不校验,如果不为空,则校验
- */
- @Pattern(regexp="^[0-9]{4}-[0-9]{2}-[0-9]{2}$",message="出生日期格式不正确")
- private String birthday;
- @NotBlank(message="学校不能为空")
- private String school;
- public String getUserName() {
- return userName;
- }
- public void setUserName(String userName) {
- this.userName = userName;
- }
- public String getAge() {
- return age;
- }
- public void setAge(String age) {
- this.age = age;
- }
- public String getBirthday() {
- return birthday;
- }
- public void setBirthday(String birthday) {
- this.birthday = birthday;
- }
- public String getSchool() {
- return school;
- }
- public void setSchool(String school) {
- this.school = school;
- }
- }
- package com.fei.util;
- import java.util.HashMap;
- import java.util.Map;
- import java.util.Set;
- import javax.validation.ConstraintViolation;
- import javax.validation.Validation;
- import javax.validation.Validator;
- import javax.validation.groups.Default;
- public class ValidatorUtil {
- private static Validator validator = Validation.buildDefaultValidatorFactory()
- .getValidator();
- public static <T> Map<String,StringBuffer> validate(T obj){
- Map<String,StringBuffer> errorMap = null;
- Set<ConstraintViolation<T>> set = validator.validate(obj,Default.class);
- if(set != null && set.size() >0 ){
- errorMap = new HashMap<String,StringBuffer>();
- String property = null;
- for(ConstraintViolation<T> cv : set){
- //这里循环获取错误信息,可以自定义格式
- property = cv.getPropertyPath().toString();
- if(errorMap.get(property) != null){
- errorMap.get(property).append("," + cv.getMessage());
- }else{
- StringBuffer sb = new StringBuffer();
- sb.append(cv.getMessage());
- errorMap.put(property, sb);
- }
- }
- }
- return errorMap;
- }
- }
- package com.fei;
- import java.util.Map;
- import com.fei.info.StudentInfo;
- import com.fei.util.ValidatorUtil;
- public class ValidatorTest {
- public static void main(String[] args) {
- StudentInfo s = new StudentInfo();
- long startTime = System.currentTimeMillis();
- print(ValidatorUtil.validate(s));
- System.out.println("===============耗时(毫秒)=" + (System.currentTimeMillis() - startTime));
- s.setUserName("小明");
- s.setAge("a10");
- s.setBirthday("2016-9-1");
- startTime = System.currentTimeMillis();
- print(ValidatorUtil.validate(s));
- System.out.println("===============耗时(毫秒)=" + (System.currentTimeMillis() - startTime));
- }
- private static void print(Map<String,StringBuffer> errorMap){
- if(errorMap != null){
- for(Map.Entry<String, StringBuffer> m : errorMap.entrySet()){
- System.out.println(m.getKey() + ":" + m.getValue().toString());
- }
- }
- }
- }
来看看运行结果:
- 十二月 12, 2016 4:02:00 下午 org.hibernate.validator.internal.util.Version <clinit>
- INFO: HV000001: Hibernate Validator 5.1.3.Final
- school:学校不能为空
- age:年龄不能为空
- userName:用户名不能为空
- ===============耗时(毫秒)=280
- birthday:出生日期格式不正确
- school:学校不能为空
- age:年龄是整数
- ===============耗时(毫秒)=3
看StudentInfo中的import发现注解的来源有来自javax和hibernate。
javax中有
hibernate中有
如果现有的校验规则都不满足,则可以自定义校验规则
3.自定义校验规则
Money.java
- package com.fei.validator;
- import java.lang.annotation.ElementType;
- import java.lang.annotation.Retention;
- import java.lang.annotation.RetentionPolicy;
- import java.lang.annotation.Target;
- import javax.validation.Constraint;
- import javax.validation.Payload;
- @Target({ElementType.FIELD, ElementType.METHOD})
- @Retention(RetentionPolicy.RUNTIME)
- @Constraint(validatedBy=MoneyValidator.class)
- public @interface Money {
- String message() default"不是金额形式";
- Class<?>[] groups() default {};
- Class<? extends Payload>[] payload() default {};
- }
MoneyValidator.java
- package com.fei.validator;
- import java.util.regex.Pattern;
- import javax.validation.ConstraintValidator;
- import javax.validation.ConstraintValidatorContext;
- public class MoneyValidator implements ConstraintValidator<Money, Double> {
- private String moneyReg = "^\\d+(\\.\\d{1,2})?$";//表示金额的正则表达式
- private Pattern moneyPattern = Pattern.compile(moneyReg);
- public void initialize(Money money) {
- // TODO Auto-generated method stub
- }
- public boolean isValid(Double value, ConstraintValidatorContext arg1) {
- if (value == null)
- //金额是空的,返回true,是因为如果null,则会有@NotNull进行提示
- //如果这里false的话,那金额是null,@Money中的message也会进行提示
- //自己可以尝试
- return true;
- return moneyPattern.matcher(value.toString()).matches();
- }
- }
StudentInfo.java
加上,注意因为money是Double,所以不能用@NotBlank,因为@NotBlank是对字符串校验的
- @NotNull(message="金额不能为空")
- @Money(message="金额格式不正确")
- private Double money;
ValidatorTest.java
- package com.fei;
- import java.util.Map;
- import com.fei.info.StudentInfo;
- import com.fei.util.ValidatorUtil;
- public class ValidatorTest {
- public static void main(String[] args) {
- StudentInfo s = new StudentInfo();
- long startTime = System.currentTimeMillis();
- print(ValidatorUtil.validate(s));
- System.out.println("===============耗时(毫秒)=" + (System.currentTimeMillis() - startTime));
- s.setUserName("小明");
- s.setAge("a10");
- s.setBirthday("2016-9-1");
- s.setMoney(100.00001);
- startTime = System.currentTimeMillis();
- print(ValidatorUtil.validate(s));
- System.out.println("===============耗时(毫秒)=" + (System.currentTimeMillis() - startTime));
- }
- private static void print(Map<String,StringBuffer> errorMap){
- if(errorMap != null){
- for(Map.Entry<String, StringBuffer> m : errorMap.entrySet()){
- System.out.println(m.getKey() + ":" + m.getValue().toString());
- }
- }
- }
- }
- 十二月 12, 2016 4:42:41 下午 org.hibernate.validator.internal.util.Version <clinit>
- INFO: HV000001: Hibernate Validator 5.1.3.Final
- school:学校不能为空
- age:年龄不能为空
- money:金额不能为空
- userName:用户名不能为空
- ===============耗时(毫秒)=280
- birthday:出生日期格式不正确
- school:学校不能为空
- age:年龄是整数
- money:金额格式不正确
- ===============耗时(毫秒)=4
当然,如果你的项目使用springMVC或structs2,都会对应的集成方法。
4.级联校验
如果校验的对象中包含另一个对象信息时,校验也要同时校验另一个对象,则可以使用@Valid
ParentInfo.java
- package com.fei.info;
- import org.hibernate.validator.constraints.NotBlank;
- public class ParentInfo {
- @NotBlank(message="父亲名称不能为空")
- private String fatherName;
- @NotBlank(message="母亲名称不能为空")
- private String motherName;
- public String getFatherName() {
- return fatherName;
- }
- public void setFatherName(String fatherName) {
- this.fatherName = fatherName;
- }
- public String getMotherName() {
- return motherName;
- }
- public void setMotherName(String motherName) {
- this.motherName = motherName;
- }
- }
中加入,set,get是必须的
- /**
- * 如果不加@NotNull,则prentInfo=null时,不会对ParentInfo内的字段进行校验
- */
- @NotNull(message="父母信息不能为空")
- @Valid
- private ParentInfo parentInfo;
- package com.fei;
- import java.util.Map;
- import com.fei.info.ParentInfo;
- import com.fei.info.StudentInfo;
- import com.fei.util.ValidatorUtil;
- public class ValidatorTest {
- public static void main(String[] args) {
- StudentInfo s = new StudentInfo();
- long startTime = System.currentTimeMillis();
- print(ValidatorUtil.validate(s));
- System.out.println("===============耗时(毫秒)=" + (System.currentTimeMillis() - startTime));
- s.setUserName("小明");
- s.setAge("a10");
- s.setBirthday("2016-9-1");
- s.setMoney(100.00001);
- s.setParentInfo(new ParentInfo());
- startTime = System.currentTimeMillis();
- print(ValidatorUtil.validate(s));
- System.out.println("===============耗时(毫秒)=" + (System.currentTimeMillis() - startTime));
- }
- private static void print(Map<String,StringBuffer> errorMap){
- if(errorMap != null){
- for(Map.Entry<String, StringBuffer> m : errorMap.entrySet()){
- System.out.println(m.getKey() + ":" + m.getValue().toString());
- }
- }
- }
- }
运行结果:
- 十二月 12, 2016 4:56:16 下午 org.hibernate.validator.internal.util.Version <clinit>
- INFO: HV000001: Hibernate Validator 5.1.3.Final
- parentInfo:父母信息不能为空
- school:学校不能为空
- age:年龄不能为空
- money:金额不能为空
- userName:用户名不能为空
- ===============耗时(毫秒)=285
- birthday:出生日期格式不正确
- school:学校不能为空
- parentInfo.fatherName:父亲名称不能为空
- age:年龄是整数
- parentInfo.motherName:母亲名称不能为空
- money:金额格式不正确
- ===============耗时(毫秒)=9
转自:https://blog.****.net/dream_broken/article/details/53584169