同一個(gè)目標(biāo)，同一個(gè)夢(mèng)想

Common BeanUtils組件方便了對(duì)JavaBean的使用。其中的一些類方法，使我們使用JavaBean得到了便利。

使用Common BeanUtils組件需要三個(gè)Jar包，分別是

commons-beanutils-1.8.0-BETA.jar

commons-logging-1.1.1.jar

commons-logging-api-1.1.1.jar

可從官網(wǎng)下載，不過為了方便，我把三個(gè)包傳上來。點(diǎn)擊下載

下面用四個(gè)例子說明該組件的三個(gè)優(yōu)點(diǎn)。

例子一:

創(chuàng)建三個(gè)Java文件，分別為

Address.java

Profile.java

User.java

在寫一個(gè)類文件遞進(jìn)調(diào)用函數(shù)，命名：BeanUtilsExample1.java，源碼：

Code
package com.sy;

import java.util.Map;
import java.util.HashMap;
import java.util.GregorianCalendar;
import org.apache.commons.beanutils.BeanUtils;
import org.apache.commons.beanutils.PropertyUtils;

public class BeanUtilsExample1 {
    private User prepareData() {
        Profile profile = new Profile();
        profile.setEmail("shiyangxt@126.com");
        profile.setBirthDate(new GregorianCalendar(3212, 9, 10).getTime());
        Map<String, String> phone = new HashMap<String, String>();
        phone.put("home", "11011011");
        phone.put("office", "82826905");
        profile.setPhone(phone);
        Address[] address = { new Address("中國(guó)", "北京", "100120", "天安門北大街888號(hào)"),
                new Address("中國(guó)", "廣州", "100120", "石牌村666號(hào)") };
        profile.setAddress(address);

        User user = new User();
        user.setUserId(new Long(123456789));
        user.setUsername("shiyang");
        user.setPassword("12345");
        user.setProfile(profile);
        return user;
    }

    public static void main(String[] args) {
        BeanUtilsExample1 example = new BeanUtilsExample1();
        User user = example.prepareData();
        try {
            System.out.println("輸出對(duì)象的屬性值---------------------------------");
            System.out.println(BeanUtils.getProperty(user, "userId"));
            System.out.println(BeanUtils.getProperty(user, "username"));//返回字符型
            System.out.println(PropertyUtils.getProperty(user, "username"));//返回對(duì)象類型
            System.out.println(BeanUtils.getProperty(user, "profile.email"));//重點(diǎn)
            System.out
                    .println(BeanUtils.getProperty(user, "profile.birthDate"));//重點(diǎn)
            System.out.println(BeanUtils.getProperty(user,
                    "profile.phone(home)"));//重點(diǎn)
            System.out.println(BeanUtils.getProperty(user,
                    "profile.phone(office)"));//重點(diǎn)
            System.out.println(BeanUtils.getProperty(user,
                    "profile.address[0].city"));//重點(diǎn)
            System.out.println(BeanUtils.getProperty(user,
                    "profile.address[1].city"));//重點(diǎn)

            User user2 = new User();
            BeanUtils.copyProperties(user2, user);
            //兩層拷貝，基本類型復(fù)制值，對(duì)于引用類型（除String，封裝類型外）復(fù)制地址值。
            System.out.println("輸出復(fù)制屬性的屬性值-------------------------------");
            System.out.println(BeanUtils.getProperty(user, "username"));
            System.out
                    .println(BeanUtils.getProperty(user, "profile.birthDate"));//重點(diǎn)
            System.out.println(BeanUtils.getProperty(user,
                    "profile.phone(home)"));//重點(diǎn)
            System.out.println(BeanUtils.getProperty(user,
                    "profile.address[0].addr"));//重點(diǎn)

            System.out.println("輸出復(fù)制屬性修改以后的屬性值---------------------");
            BeanUtils.setProperty(user2, "userId", new Long(8888888));
            PropertyUtils.setProperty(user2, "username", "ahah");
            BeanUtils.setProperty(user2, "profile.email", "shiyangxt@126.com");//重點(diǎn)
            BeanUtils.setProperty(user2, "profile.birthDate",//重點(diǎn)
                    new GregorianCalendar(1900, 2, 5).getTime());
            BeanUtils.setProperty(user2, "profile.address[0]", new Address(
                    "中國(guó)", "深圳", "600600", "深北大道111號(hào)"));//重點(diǎn)
            System.out.println(BeanUtils.getProperty(user2, "userId"));
            System.out.println(BeanUtils.getProperty(user2, "username"));
            System.out.println(BeanUtils.getProperty(user2, "profile"));
            System.out.println(BeanUtils.getProperty(user2, "profile.email"));//重點(diǎn)
            System.out.println(BeanUtils
                    .getProperty(user2, "profile.birthDate"));//重點(diǎn)
            System.out.println(BeanUtils.getProperty(user2,
                    "profile.address[0].city"));//重點(diǎn)

            System.out.println("與被復(fù)制屬性值的對(duì)象的比較-------------------------------");
            System.out.println(BeanUtils.getProperty(user, "userId"));
            System.out.println(BeanUtils.getProperty(user, "username"));
            System.out.println(BeanUtils.getProperty(user, "profile"));
            System.out.println(BeanUtils.getProperty(user, "profile.email"));//重點(diǎn)
            System.out
                    .println(BeanUtils.getProperty(user, "profile.birthDate"));//重點(diǎn)
            System.out.println(BeanUtils.getProperty(user,
                    "profile.address[0].city"));//重點(diǎn)
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

從中可以看出，

調(diào)用一個(gè)屬性中的方法，只需要加一個(gè)“.”即可。精簡(jiǎn)了操作。

還可以拷貝屬性，但要注意是二層拷貝。

還要注意BeanUtils和PropertyUtils的區(qū)別。

例子二:

動(dòng)態(tài)創(chuàng)建屬性

文件名：BeanUtilsExample2，源碼：

Code
package com.sy;

import java.util.GregorianCalendar;
import org.apache.commons.beanutils.LazyDynaBean;
import org.apache.commons.beanutils.BeanUtils;

public class BeanUtilsExample2 {
    //動(dòng)態(tài)創(chuàng)建屬性
    public static void main(String args[]) throws Exception {

        LazyDynaBean hh = new LazyDynaBean();
        hh.set("country", "中國(guó)");
        hh.set("city", "北京");
        hh.set("postCode", "100120");
        hh.set("addr", "aaaaaaa");

        LazyDynaBean bb = new LazyDynaBean();
        bb.set("phone", "home", "11011011");
        bb.set("phone", "office", "111111");
        bb.set("email", "sh@126.com");
        bb.set("address", 0, hh);
        bb.set("birthDate", new GregorianCalendar(1990, 3, 29).getTime());

        LazyDynaBean tt = new LazyDynaBean();
        tt.set("userId", new Long(8888888));
        tt.set("gggg", "施楊");
        tt.set("password", "sgsgsgsg");
        tt.set("dddd", bb);

        System.out.println(BeanUtils.getProperty(tt, "gggg"));
        System.out.println(BeanUtils.getProperty(tt, "dddd.birthDate"));
        System.out.println(BeanUtils.getProperty(tt,
                "dddd.address[0].addr"));
        System.out
                .println(BeanUtils.getProperty(tt, "dddd.phone(office)"));
    }
}

例子三:

連接Mysql數(shù)據(jù)庫(kù)

文件名BeanUtilsExample3.java源碼：

Code
package com.sy;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Iterator;
import org.apache.commons.beanutils.DynaBean;
import org.apache.commons.beanutils.ResultSetDynaClass;

public class BeanUtilsExample3 {
    public static void main(String args[]) throws Exception {
        Connection conn = getConnection();
        PreparedStatement ps = conn
                .prepareStatement("select id,title,time from guestbook2 order by id desc");
        ResultSet rs = ps.executeQuery();

        ResultSetDynaClass rsdc = new ResultSetDynaClass(rs);//重點(diǎn)，二次封裝，對(duì)連接對(duì)象有依賴
        Iterator itr = rsdc.iterator();
        while (itr.hasNext()) {
            DynaBean bean = (DynaBean) itr.next();
            System.out.print(bean.get("id") + "\t");
            System.out.print(bean.get("title") + "\t");
            System.out.println(bean.get("time"));
        }
        conn.close();
    }

    private static Connection getConnection() {
        String url = "jdbc:mysql://localhost:3306/guestbook";
        String username = "root";
        String password = "hicc";
        Connection conn = null;
        try {
            Class.forName("com.mysql.jdbc.Driver");
            conn = DriverManager.getConnection(url, username, password);
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return conn;
    }
}

例子四:

文件BeanUtilsExample4.java，源碼：

Code
package com.sy;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Iterator;
import org.apache.commons.beanutils.DynaBean;
import org.apache.commons.beanutils.RowSetDynaClass;

public class BeanUtilsExample4 {
    public static void main(String args[]) throws Exception {
        Connection conn = getConnection();
        PreparedStatement ps = conn
                .prepareStatement("select id,title,time from guestbook2 order by id desc");
        ResultSet rs = ps.executeQuery();

        RowSetDynaClass rsdc = new RowSetDynaClass(rs);
        //重點(diǎn)，與ResultSetDynaClass的區(qū)別
        conn.close();//重點(diǎn)，關(guān)閉連接后仍能讀取
        Iterator itr = rsdc.getRows().iterator();
        while (itr.hasNext()) {
            DynaBean bean = (DynaBean) itr.next();
            System.out.print(bean.get("id") + "\t");
            System.out.print(bean.get("title") + "\t");
            System.out.println(bean.get("time"));
        }
    }

    private static Connection getConnection() {
        String url = "jdbc:mysql://localhost:3306/guestbook";
        String username = "root";
        String password = "hicc";
        Connection conn = null;
        try {
            Class.forName("com.mysql.jdbc.Driver");
            conn = DriverManager.getConnection(url, username, password);
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return conn;
    }
}

這就是Common BeanUtils組件的主要應(yīng)用!!!