Commons-beanutils使用指南

一、commons-beanutils的简要介绍

commons-beanutils是一组使用程序的集合,它能容易的处理bean及属性.该工具允许你以属性名检索bean属性、根据属性排列bean、将bean转换为Map等等。

二、实例说明

1. Author

package org.abu.commons.beanutils;

import java.util.Date;

public class Author {

private String name;

private String email;

private Date birth;

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public String getEmail() {

return email;

}

public void setEmail(String email) {

this.email = email;

}

public Date getBirth() {

return birth;

}

public void setBirth(Date birth) {

this.birth = birth;

}

}

2.Book

package org.abu.commons.beanutils;

import java.util.Date;

import java.util.List;

public class Book {

private String isbn;

private String bookName;

private List<Author> authors;

private String publisher;

private Date publishDate;

public String getIsbn() {

return isbn;

}

public void setIsbn(String isbn) {

this.isbn = isbn;

}

public String getBookName() {

return bookName;

}

public void setBookName(String bookName) {

this.bookName = bookName;

}

public List<Author> getAuthors() {

return authors;

}

public void setAuthors(List<Author> authors) {

this.authors = authors;

}

public String getPublisher() {

return publisher;

}

public void setPublisher(String publisher) {

this.publisher = publisher;

}

public Date getPublishDate() {

return publishDate;

}

public void setPublishDate(Date publishDate) {

this.publishDate = publishDate;

}

}

3.测试

package org.abu.commons.beanutils;

import java.util.ArrayList;

import java.util.Date;

import java.util.List;

import org.apache.commons.beanutils.PropertyUtils;

public class BeanUtilsTest {

private Book book = new Book();

private Book copiedBook = new Book();

private List<Author> authors = new ArrayList<Author>();

public BeanUtilsTest() {

// 定义三个作者

Author author1 = new Author();

Author author2 = new Author();

Author author3 = new Author();

author1.setName("Liky");

author1.setEmail("liky@yahoo.com");

author1.setBirth(new Date());

author2.setName("John");

author2.setEmail("john@yahoo.com");

author2.setBirth(new Date());

author3.setName("Susan");

author3.setEmail("susan@yahoo.com");

author3.setBirth(new Date());

// book属性

authors.add(author1);

authors.add(author2);

authors.add(author3);

book.setAuthors(authors);

book.setIsbn("ISBN 7-096-13964-4");

book.setBookName("Struts2 in Action");

book.setPublisher("O'Reilly Media Inc.");

book.setPublishDate(new Date());

}

public static void main(String[] args) throws Exception {

BeanUtilsTest but = new BeanUtilsTest();

//but.getProperty();

but.copyProperties();

}

/**

* 演示使用PropertyUtils来获得属性,

* 注意获得属性有三种方式,分别是:

* 1.getSimpleProperty 用来获取基本数据类型的属性

* 2.getMappedProperty 用来获取Map类型的属性,

* 例如:Book有一个Map类型的author,而author中有三个key,其中一个是name.

* 那么就可以这样来使用getMappedProperty(book, "author", "name");

* 3.getNestedProperty 用来获取嵌套的属性.

* 也就是说如果Book有一个Author的属性,而Author又是另一个Bean,Author有个属性是name,

* 那么就可以这样来使用getNestedProperty(book,"author.name");

*

* @throws Exception

*/

@SuppressWarnings("unchecked")

public void getProperty() throws Exception {

// 获得Bean的简单属性

String bookName = (String) PropertyUtils.getSimpleProperty(book,

"bookName");

String publisher = (String) PropertyUtils.getSimpleProperty(book,

"publisher");

String isbn = (String) PropertyUtils.getSimpleProperty(book, "isbn");

Date publishDate = (Date) PropertyUtils.getSimpleProperty(book,

"publishDate");

StringBuffer bookString = new StringBuffer();

bookString.append("book:/n").append(

"bookName: " + bookName + "/npublisher: " + publisher

+ "/nisbn: " + isbn + "/npublish date: " + publishDate + "/n/n");

// 获得嵌套的属性,这里的Book中有一个Authors的属性,它是Author这个Bean的列表

// 如果要获得嵌套的属性,那么必须使用getNestedProperty这个方法

System.out.println(bookString);

List<Author> authorList = (List<Author>) PropertyUtils

.getNestedProperty(book, "authors");

StringBuffer authorsString = new StringBuffer();

for (int i = 0; i < authorList.size(); i++) {

Author author = authorList.get(i);

authorsString.append("author" + i + ":/n");

authorsString.append("name:"

+ PropertyUtils.getSimpleProperty(author, "name") + "/n");

authorsString.append("email:"

+ PropertyUtils.getSimpleProperty(author, "email") + "/n");

authorsString.append("birth:"

+ PropertyUtils.getSimpleProperty(author, "birth") + "/n/n");

}

System.out.println(authorsString);

}

/**

* 我们来测试是否book会复制属性给copiedBook.

* @throws Exception

*/

public void copyProperties() throws Exception {

PropertyUtils.copyProperties(copiedBook, book);

StringBuffer sb = new StringBuffer();

sb.append("book:/n").append("bookName: " + copiedBook.getBookName()).append("/npublisher: " + copiedBook.getPublisher()).append("/npublish date: " + copiedBook.getPublishDate());

System.out.println(sb);

}

}