Mingyang.net：用注解校验数据

<dependency>
    <groupId>javax.validation</groupId>
    <artifactId>validation-api</artifactId>
    <version>1.1.0.Final</version>
</dependency>
<dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-validator</artifactId>
    <version>5.0.1.Final</version>
</dependency>

<mvc:annotation-driven />

public class Subscriber {
 
    @Size(min=2, max=30) 
    private String name;
     
    @NotEmpty @Email
    private String email;
     
    @NotNull @Min(13) @Max(110)
    private Integer age;
     
    @Size(min=10)
    private String phone;
     
    @NotNull
    private Gender gender;
     
    @DateTimeFormat(pattern="MM/dd/yyyy")
    @NotNull @Past
    private Date birthday;
 
    ...
}

@Controller
public class FormController {
     
    ...
     
    @RequestMapping(value="form", method=RequestMethod.POST)
    public String submitForm(@Valid Subscriber subscriber, BindingResult result, Model m) {
        if(result.hasErrors()) {
            return "formPage";
        }
         
        m.addAttribute("message", "Successfully saved person: " + subscriber.toString());
        return "formPage";
    }
}

<form:form action="/form" modelattribute="subscriber">
    <label for="nameInput">Name: </label>
    <form:input path="name" id="nameInput"></form:input>
    <form:errors path="name" cssclass="error"></form:errors>
    <br />
     
    <label for="ageInput">Age: </label>
    <form:input path="age" id="ageInput"></form:input>
    <form:errors path="age" cssclass="error"></form:errors>
    <br />
     
    <label for="phoneInput">Phone: </label>
    <form:input path="phone" id="phoneInput"></form:input>
    <form:errors path="phone" cssclass="error"></form:errors>
    <br />
     
    <label for="emailInput">Email: </label>
    <form:input path="email" id="emailInput"></form:input>
    <form:errors path="email" cssclass="error"></form:errors>
    <br />
     
    <label for="birthdayInput">Birthday: </label>
    <form:input path="birthday" id="birthdayInput" placeholder="MM/DD/YYYY">
    <form:errors path="birthday" cssclass="error"></form:errors>
    <br />
     
    <label for="genderOptions">Gender: </label>
    <form:select path="gender" id="genderOptions">
        <form:option value="">Select Gender</form:option>
        <form:option value="MALE">Male</form:option>
        <form:option value="FEMALE">Female</form:option>
    </form:select>
    <form:errors path="gender" cssclass="error"></form:errors>
    <br />
     
    <label for="newsletterCheckbox">Newsletter? </label>
    <form:checkbox path="receiveNewsletter" id="newsletterCheckbox"></form:checkbox>
    <form:errors path="receiveNewsletter" cssclass="error"></form:errors>
    <br /><br />
    <input type="submit" value="Submit" />
</form:input></form:form>

@Size(min=10, message="Phone number must be at least 10 characters")

<bean id="messageSource" class="org.springframework.context.support.ResourceBundleMessageSource">
    <property name="basename" value="messages"/>
</bean>

{ValidationClass}.{modelObjectName}.{field}

Size=the {0} field must be between {2} and {1} characters long
Size.subscriber.name=Name must be between {2} and {1} characters
Size.subscriber.phone=Phone must be at least {2} characters
 
Min.subscriber.age=You must be older than {1}
Max.subscriber.age= Sorry, you have to be younger than {1}
 
Email=Email address not valid
Past=Date must be in the past
 
NotEmpty=Field cannot be left blank
NotNull=Field cannot be left blank
 
typeMismatch=Invalid format
methodInvocation.myRequest.amount=Invalid format

For example, if the age field of our “subscriber” model object fails the “NotNull” validation, the “NotNull.subscriber.age” message would be looked up. If the message isn’t found, “NotNull.subscriber” would be looked for. Finally, if not found, “NotNull” message would be looked for. If that also isn’t found, the default message (what we saw above) would be rendered.