注释可以限制 java 中 class 字段的字符吗？

Question

我正在使用 java 1.8，Spring Boot 和 MongoDb 在数据库中存储一些数据以了解 mongoDb

我想通过注释限制 class 字段的字符我试图用 hibernate-validator 控制它：

import javax.validation.constraints.Size;
import org.springframework.data.annotation.Id;
import org.springframework.data.mongodb.core.mapping.Document;
import org.springframework.data.mongodb.core.mapping.Field;

@Document(collection = "MusicGroup")
public class MusicGroup {

    @Id
    private String id;
    @Size(min = 7, max = 7, message = "title need to have only 4 characters")
    @Field("Title")
    private String title;
    @Size(min = 11, max = 11, message = "type need to have only 11 characters")
    @Field("Type")
    private String type;
    @Field("Members")
    private List<String> members;

    public MusicGroup(String titulo, String tipo, List<String> integrantes) {
        this.title = titulo;
        this.type = tipo;
        this.members = integrantes;
    }

但是当我将其插入 mongodb 代码时：

@Service
public class MusicGroupServiceImpl implements MusicGroupService {

    @Autowired
    private MusicGroupRepository repository;

    public MusicGroupServiceImpl() {

    }

    @Override
    public void storeGroup(){

        String[] memberList = new String[3];
        memberList[0] = "A";
        memberList[1] = "B";
        memberList[2] = "C";

        MusicGroup group = new MusicGroup("Panteraaaaaa", "Heavy Metallllllllllllllll", memberList);

        repository.save(group);

    }

}

当 Panteraaaaaa 的长度大于 7 且 Heavy Metallllllllllllllll 相同时，它确实可以正常工作

我附上以下对应于我的 pom.xml

的代码

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.3.RELEASE</version>
        <relativePath/>
    </parent>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-mongodb</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.mongodb/mongo-java-driver 
        <dependency>
            <groupId>org.mongodb</groupId>
            <artifactId>mongo-java-driver</artifactId>
            <version>3.4.2</version>
        </dependency>-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.hamcrest</groupId>
            <artifactId>hamcrest-core</artifactId>
            <version>1.3</version>
            <scope>test</scope>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.google.code.gson/gson -->
        <dependency>
            <groupId>com.google.code.gson</groupId>
            <artifactId>gson</artifactId>
            <version>2.8.0</version>
            <type>jar</type>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-validator -->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-validator</artifactId>
            <version>5.4.1.Final</version>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

实现题是否可以通过注释控制 java 中字段字符的长度？或者我需要做一个方法来控制这个

Answer 1

您没有验证对象。只是给予限制。你能使你的方法像下面这样获取对象并重试吗？

storeGroup (@Validated MusicGroup group) {
....
}

编辑：检查@Validated 和@Valid 注释。

Answer 2

大家好我终于找到了字段验证大小的解决方案

我只需要在这里做一个新的class代码：

import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.data.mongodb.core.mapping.event.ValidatingMongoEventListener;
import org.springframework.validation.beanvalidation.LocalValidatorFactoryBean;

@SpringBootApplication
public class Configuration {

    @Bean
    public ValidatingMongoEventListener validatingMongoEventListener() {
        return new ValidatingMongoEventListener(validator());
    }

    @Bean
    public LocalValidatorFactoryBean validator() {
        return new LocalValidatorFactoryBean();
    }
}

然后将尺寸注释的位置更改为setter

@Document(collection = "MusicGroup")
public class MusicGroup {

    @Id
    private String id;
    @Field("Title")
    private String title;
    @Field("Type")
    private String type;
    @Field("Members")
    private String[] members;

    public MusicGroup() {
    }

    @Size(min = 7, max = 7)
    public String getTitle() {
        return title;
    }

    @Size(min = 11, max = 11)
    public String getType() {
        return type;
    }

    // Other getters, setters and to String()

}

添加到 pom：

    <dependency>
        <groupId>org.glassfish.web</groupId>
        <artifactId>el-impl</artifactId>
        <version>2.2</version>
    </dependency>

当我创建一个新对象 MusicGroup 时：

String[] memberList = new String[3];
memberList[0] = "typeA";
memberList[1] = "typeB";
memberList[2] = "typec";

MusicGroup grupo = new MusicGroup();

grupo.setType("888888888889");
grupo.setTitle("hhhhhhh");
grupo.setIntegrantes(memberList);

musicaService.storeGroup(grupo);

如果你在运行程序时这样做，它会给出这样的异常：

java.lang.IllegalStateException: Failed to execute CommandLineRunner
    at org.springframework.boot.SpringApplication.callRunner(SpringApplication.java:779) [spring-boot-1.5.3.RELEASE.jar:1.5.3.RELEASE]
    at org.springframework.boot.SpringApplication.callRunners(SpringApplication.java:760) [spring-boot-1.5.3.RELEASE.jar:1.5.3.RELEASE]
    at org.springframework.boot.SpringApplication.afterRefresh(SpringApplication.java:747) [spring-boot-1.5.3.RELEASE.jar:1.5.3.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) [spring-boot-1.5.3.RELEASE.jar:1.5.3.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1162) [spring-boot-1.5.3.RELEASE.jar:1.5.3.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1151) [spring-boot-1.5.3.RELEASE.jar:1.5.3.RELEASE]
    at es.cic.cmunoz.MongoDbMascotaApplication.main(MongoDbMascotaApplication.java:32) [classes/:na]
Caused by: javax.validation.ConstraintViolationException: null
    at org.springframework.data.mongodb.core.mapping.event.ValidatingMongoEventListener.onBeforeSave(ValidatingMongoEventListener.java:67) ~[spring-data-mongodb-1.10.3.RELEASE.jar:na]
    ...

但是如果您在此方法中输入有效的字符串

grupo.setType("88888888888");

它不会给你任何异常

感谢 dunni 的评论，它引导我找到解决方案

PD：如果你想验证像 int 这样的数字字段，你需要在 getter 方法中使用 @Max(Number) 或 @Min(Number)

有关详细信息，请参阅此文档：http://docs.jboss.org/hibernate/validator/5.1/reference/en-US/html/chapter-message-interpolation.html#section-resource-bundle-locator

添加自定义消息：https://raymondhlee.wordpress.com/2014/07/26/including-field-value-in-validation-message-using-spring-validation-framework-for-jsr-303/

注释可以限制 java 中 class 字段的字符吗？

Can annotations limit the characters of a class field in java?

java

spring-data-mongodb

spring-boot

java-annotations