一、作用

用来做对象间的copy。

二、举例

（1）新建两个实体类

package org.example;import java.util.Date;public class Student {private String name;private String age;private String tel;private Boolean isno;private Date time;public Student() {}public Student(String name, String age, String tel, Boolean isno, Date time) {this.name = name;this.age = age;this.tel = tel;this.isno = isno;this.time = time;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getAge() {return age;}public void setAge(String age) {this.age = age;}public String getTel() {return tel;}public void setTel(String tel) {this.tel = tel;}public Boolean getIsno() {return isno;}public void setIsno(Boolean isno) {this.isno = isno;}public Date getTime() {return time;}public void setTime(Date time) {this.time = time;}@Overridepublic String toString() {return "Student{" +"name='" + name + '\'' +", age=" + age +", tel='" + tel + '\'' +", isno=" + isno +", time=" + time +'}';}
}

package org.example;import java.util.Date;
import java.util.Objects;public class Person {private String name;private int age;private String phone;private Boolean isno;private Date time;public Person() {}public Person(String name, int age, String phone, Boolean isno, Date time) {this.name = name;this.age = age;this.phone = phone;this.isno = isno;this.time = time;}public String getName() {return name;}public void setName(String name) {this.name = name;}public int getAge() {return age;}public void setAge(int age) {this.age = age;}public String getPhone() {return phone;}public void setPhone(String phone) {this.phone = phone;}public Boolean getIsno() {return isno;}public void setIsno(Boolean isno) {this.isno = isno;}public Date getTime() {return time;}public void setTime(Date time) {this.time = time;}@Overridepublic boolean equals(Object o) {if (this == o) return true;if (o == null || getClass() != o.getClass()) return false;Person person = (Person) o;return Objects.equals(name, person.name) && Objects.equals(age, person.age) && Objects.equals(phone, person.phone);}@Overridepublic int hashCode() {return Objects.hash(name, age, phone);}@Overridepublic String toString() {return "Person{" +"name='" + name + '\'' +", age=" + age +", phone='" + phone + '\'' +", isno=" + isno +", time=" + time +'}';}
}

（2）pom引入依赖

因为BeanUtils依赖于spring-beans的依赖包

<!-- https://mvnrepository.com/artifact/org.springframework/spring-beans --><dependency><groupId>org.springframework</groupId><artifactId>spring-beans</artifactId><version>5.1.5.RELEASE</version></dependency><dependency><groupId>org.slf4j</groupId><artifactId>jcl-over-slf4j</artifactId><version>1.7.22</version></dependency>

（3）main方法测试

    public static void main(String[] args) {Student student = new Student("zhangsan", "23", "2324234",true,new Date());Person person = new Person("LISI", 12, "876543",false,new Date(2017,9,9));BeanUtils.copyProperties(student, person);System.out.println(student);System.out.println(person);}

（4）结果输出

Student{name='zhangsan', age=23, tel='2324234', isno=true, time=Mon May 06 17:49:42 CST 2024}
Person{name='zhangsan', age=23, phone='876543', isno=true, time=Mon May 06 17:49:42 CST 2024}

（5）结论

只要两个实体的属性名称和类型都相同，就可以做到拷贝
BeanUtils.copyProperties(A,B);
把A拷贝到B