验证对象邮箱是否符合规范，两次的密码是否一致

UserDto：

package com.imooc.uaa.domain.dto;

import com.imooc.uaa.validation.annotation.PasswordMatches;
import com.imooc.uaa.validation.annotation.ValidEmail;
import com.imooc.uaa.validation.annotation.ValidPassword;
import lombok.Data;

import javax.validation.constraints.NotBlank;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;
import java.io.Serializable;

@PasswordMatches
@Data
public class UserDto implements Serializable {
    @NotNull
    @NotBlank
    @Size(min = 4, max = 50, message = "用户名长度必须在4到50个字符之间")
    private String username;
    @NotNull
    @ValidPassword
    private String password;
    @NotNull
    private String matchingPassword;
    @NotNull
    @ValidEmail
    private String email;
    @NotNull
    @NotBlank
    @Size(min = 4, max = 50, message = "姓名长度必须在4到50个字符之间")
    private String name;
}

 添加邮箱的验证注解ValidEmail

package com.imooc.uaa.validation.annotation;

import com.imooc.uaa.validation.EmailValidator;

import javax.validation.Constraint;
import javax.validation.Payload;
import java.lang.annotation.Documented;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;

import static java.lang.annotation.ElementType.ANNOTATION_TYPE;
import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.ElementType.TYPE;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

@Target({ TYPE, FIELD, ANNOTATION_TYPE })
@Retention(RUNTIME)
@Constraint(validatedBy = EmailValidator.class)
@Documented
public @interface ValidEmail {

    String message() default "{ValidEmail.email}";

    Class<?>[] groups() default {};

    Class<? extends Payload>[] payload() default {};
}

EmailValidator：

package com.imooc.uaa.validation;

import com.imooc.uaa.validation.annotation.ValidEmail;
import lombok.val;

import javax.validation.ConstraintValidator;
import javax.validation.ConstraintValidatorContext;
import java.util.regex.Pattern;

public class EmailValidator implements ConstraintValidator<ValidEmail, String> {
    private static final String EMAIL_PATTERN = "^[_A-Za-z0-9-\\+]+(\\.[_A-Za-z0-9-]+)*@" + "[A-Za-z0-9-]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z]{2,})$";

    @Override
    public void initialize(final ValidEmail constraintAnnotation) {}

    @Override
    public boolean isValid(final String username, final ConstraintValidatorContext context) {
        return (validateEmail(username));
    }

    private boolean validateEmail(final String email) {
        val pattern = Pattern.compile(EMAIL_PATTERN);
        val matcher = pattern.matcher(email);
        return matcher.matches();
    }
}

密码两次校验是否相同：

PasswordMatches：

package com.imooc.uaa.validation.annotation;

import com.imooc.uaa.validation.PasswordMatchesValidator;

import static java.lang.annotation.ElementType.ANNOTATION_TYPE;
import static java.lang.annotation.ElementType.TYPE;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

import java.lang.annotation.Documented;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;

import javax.validation.Constraint;
import javax.validation.Payload;

@Target({ TYPE, ANNOTATION_TYPE })
@Retention(RUNTIME)
@Constraint(validatedBy = PasswordMatchesValidator.class)
@Documented
public @interface PasswordMatches {

    String message() default "{PasswordMatches.userDto}";

    Class<?>[] groups() default {};

    Class<? extends Payload>[] payload() default {};

}

添加注解对应的实现：

package com.imooc.uaa.validation;

import com.imooc.uaa.domain.dto.UserDto;
import com.imooc.uaa.validation.annotation.PasswordMatches;
import lombok.val;

import javax.validation.ConstraintValidator;
import javax.validation.ConstraintValidatorContext;

public class PasswordMatchesValidator implements ConstraintValidator<PasswordMatches, UserDto> {

    @Override
    public void initialize(final PasswordMatches constraintAnnotation) { }

    @Override
    public boolean isValid(final UserDto obj, final ConstraintValidatorContext context) {
        val user = (UserDto) obj;
        return user.getPassword().equals(user.getMatchingPassword());
    }
}

使用的依赖：

<dependency>

            <groupId>org.passay</groupId>

            <artifactId>passay</artifactId>

            <version>1.6.0</version> 

       </dependency>