Java如何读取bean的嵌套属性值？
在这个示例中，您将看到如何读取bean的嵌套属性，我们将使用 PropertyUtils.getNestedProperty()方法。为了进行测试，我们将为bean创建三个类:Track和 Artist，并将ReadNestedProperty作为主程序运行。
Track类将包含的属性Artist对象。使用PropertyUtils.getNestedProperty()方法，我们想要获得演唱曲目的歌手姓名。此方法将首先从track对象读取artist属性，然后读取artist对象的name属性。
使用PropertyUtils.getNestedProperty()它读取嵌套属性可以无限读取嵌套级别。
package org.nhooo.example.commons.beanutils;
import org.apache.commons.beanutils.PropertyUtils;
public class ReadNestedProperty {
public static void main(String[] args) {
Track track = new Track();
track.setId(1L);
track.setTitle("All My Loving");
track.setArtist(new Artist(1L, "Beatles"));
try {
String artistName = (String) PropertyUtils.getNestedProperty(track, "artist.name");
System.out.println("Artist Name = " + artistName);
} catch (Exception e) {
e.printStackTrace();
}
}
}package org.nhooo.example.commons.beanutils;
public class Track {
private Long id;
private String title;
private Integer duration;
private Artist artist;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public Integer getDuration() {
return duration;
}
public void setDuration(Integer duration) {
this.duration = duration;
}
public Artist getArtist() {
return artist;
}
public void setArtist(Artist artist) {
this.artist = artist;
}
@Override
public String toString() {
return "Track{" +
"id=" + id +
", title='" + title + '\'' +
", duration=" + duration +
'}';
}
}package org.nhooo.example.commons.beanutils;
public class Artist {
private Long id;
private String name;
public Artist() {
}
public Artist(Long id, String name) {
this.id = id;
this.name = name;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}Maven依赖
<!-- https://search.maven.org/remotecontent?filepath=commons-beanutils/commons-beanutils/1.9.3/commons-beanutils-1.9.3.jar -->
<dependency>
<groupId>commons-beanutils</groupId>
<artifactId>commons-beanutils</artifactId>
<version>1.9.3</version>
</dependency>