Entity objects transfer values to each other. For example, assigning the value of VO object to entity object is a common function in the code. It is troublesome to assign values to each other through get and set. The operation can be easily completed with the help of tool class BeanUtils.

BeanUtils dependent package import

BeanUtils is a member of the Apache commons component, which is mainly used to simplify the operation of JavaBean s encapsulating data. To use BeanUtils, you must import the corresponding jar package. The maven coordinate of BeanUtils is

<dependency>
    <groupId>commons-beanutils</groupId>
    <artifactId>commons-beanutils</artifactId>
    <version>1.9.4</version>
</dependency>

Examples

Assign the student ranking information (StudentVo object) from the front end to the student object (StudentEntity) and ranking object (RankingEntity) respectively. The codes of these three classes are as follows:

@Data
public class StudentVo {
    private String sno;
    private String sname;
    private Integer ranking;
    private String schoolTerm;

    public String toString(){
        return "studentVo The value of the object  sno:"+getSno()+" sname:"+getSname()+" ranking:"+getRanking().toString()+" schoolTerm:"+getSchoolTerm();
    }
}

@Data
public class StudentEntity {
    private String sno;
    private String sname;
    private Integer sage;

    public String toString(){
        return "studentEntity The value of the object sno:"+getSno()+" sname:"+getSname()+" sage:"+getSage();
    }
}

@Data
public class RankingEntity {
    private String sno;
    private Integer ranking;
    private String schoolTerm;

    public String toString(){
        return "rankingEntity Value student number of object:"+getSno()+" Ranking:"+getRanking().toString()+" semester:"+getSchoolTerm();
    }
}

Assign the value of VO object to entity object through BeanUtils Copyproperties (target, source): assign the data of the source entity object to the target object, and only assign the data with the same property name. If the property in the target does not exist in the source, give null value. The test code is as follows:

public class App {
    public static void main( String[] args ) throws InvocationTargetException, IllegalAccessException {
        StudentVo studentVo = new StudentVo();
        studentVo.setSno("1");
        studentVo.setRanking(20);
        studentVo.setSname("Hu Cheng");
        studentVo.setSchoolTerm("The third semester");

        System.out.println(studentVo.toString());
        StudentEntity studentEntity = new StudentEntity();

        BeanUtils.copyProperties(studentEntity,studentVo);
        System.out.println(studentEntity.toString());

        RankingEntity rankingEntity = new RankingEntity();
        BeanUtils.copyProperties(rankingEntity,studentVo);
        System.out.println(rankingEntity.toString());
    }
}

Operation results:

Ending

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