BeanUtils_BeanUtils

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1. beanUtils工程

1.工程目录

2.需要的jar包：
commons-beanutils-1.9.3.jar
commons-collections-3.2.2.jar
commons-logging-1.2.jar
3.转换器
DateConverter.java:

package com.my.model;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;

import org.apache.commons.beanutils.ConvertUtils;
import org.apache.commons.beanutils.converters.AbstractConverter;
import org.apache.commons.beanutils.converters.DateTimeConverter;

public class DateConverter<T> extends org.apache.commons.beanutils.converters.DateTimeConverter { 
   
    private SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");
    @Override
    /** * arg0 转换的目的类型 * arg1 需要转换的数值 * @return 返回转换后的数值 */
    public <T> T convert(Class<T> clz, Object value) {
        //1.转换的类型是否符合要求
        if(Date.class!=clz) {
            return null;
        }
        if(value instanceof String) {
            try {
                return (T) sdf.parse((String)value);
            } catch (ParseException e) {
                e.printStackTrace();
            }
        }
        return null;
    }

    @Override
    protected Object convertArray(Object arg0) {
        return super.convertArray(arg0);
    }

    @Override
    protected Class<?> getDefaultType() {
        return null;
    }

}

PointConvert.java:

package com.my.model;

import org.apache.commons.beanutils.converters.AbstractConverter;

public class PointConvert<T> extends AbstractConverter{ 
   

    @Override
    public <T> T convert(Class<T> clz, Object value) {
        if(Point.class!=clz) {
            return null;
        }
        if(value instanceof String) {
            String val=(String)value;
            String[] strArray=val.split(",");
            if(strArray.length<2) {
                return null;
            }
            int x=0, y=0;
            try {
                x=Integer.parseInt(strArray[0]);
                y=Integer.parseInt(strArray[1]);
            }catch(NumberFormatException e) {
                e.printStackTrace();
            }
            return (T) new Point(x, y);
        }
        return null;
    }

    @Override
    protected <T> T convertToType(Class<T> arg0, Object arg1) throws Throwable {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    protected Class<?> getDefaultType() {
        // TODO Auto-generated method stub
        return null;
    }

}

4.model类
Point.java:

package com.my.model;

public class Point{ 
   
    private int x;
    private int y;
    public int getX() {
        return x;
    }
    public void setX(int x) {
        this.x = x;
    }
    public int getY() {
        return y;
    }
    public void setY(int y) {
        this.y = y;
    }
    public Point(int x, int y) {
        this.x = x;
        this.y = y;
    }
    public Point() {
    }
    @Override
    public String toString() {
        return "Point [x=" + x + ", y=" + y + "]";
    }
}

User.java:

package com.my.model;

import java.util.Date;

public class User { 
   
    private int id;
    private String username;
    private int age;
    private String password;
    private Date born;
    private Point point;
    public Point getPoint() {
        return point;
    }
    public void setPoint(Point point) {
        this.point = point;
    }
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getUsername() {
        return username;
    }
    public void setUsername(String username) {
        this.username = username;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
    public Date getBorn() {
        return born;
    }
    public void setBorn(Date born) {
        this.born = born;
    }
    public User(int id, String username, int age, String password, Date born) {
        super();
        this.id = id;
        this.username = username;
        this.age = age;
        this.password = password;
        this.born = born;
    }
    public User() {
    }
    public User(int id, String username, int age, String password, Date born, Point point) {
        this.id = id;
        this.username = username;
        this.age = age;
        this.password = password;
        this.born = born;
        this.point = point;
    }
    @Override
    public String toString() {
        return "User [id=" + id + ", username=" + username + ", age=" + age + ", password=" + password + ", born="
                + born + ", point=" + point + "]";
    }

}

5.Junit测试类:
TestBeanUtils.java：

package com.my.test;

import static org.junit.Assert.*;

import java.lang.reflect.InvocationTargetException;
import java.util.Date;

import org.apache.commons.beanutils.BeanUtils;
import org.apache.commons.beanutils.ConvertUtils;
import org.junit.After;
import org.junit.Test;

import com.my.model.DateConverter;
import com.my.model.Point;
import com.my.model.PointConvert;
import com.my.model.User;

public class TestBeanUtils { 
   

    @Test
    public void test01() {
        User user=new User();
        User user2=new User();
        String key="username";
        String value="张三";
        try {
            BeanUtils.copyProperty(user, key, value);
            BeanUtils.copyProperty(user, "age", 1);
            BeanUtils.copyProperty(user, "age", "20");
            BeanUtils.copyProperty(user, "dass", value);
            //DateConverter does not support default String to 'Date' conversion.
            //这时候需要自己定义相应的转换器来完成转换
            //定义转换器的步骤:
            //1创建一个类让其实现Converter接口.
            //2.覆盖convert方法,在这个方法中实现转换
            //3.拷贝属性之前注册转换器
            //注册Date类型的转换器DateConverter
            ConvertUtils.register(new DateConverter<>(), Date.class);
            ConvertUtils.register(new PointConvert<>(), Point.class);
            BeanUtils.copyProperty(user, "born", "1997-2-20");
            BeanUtils.copyProperty(user, "point", "10,12");
            //BeanUtils.copyProperty(user, "born", new Date());
            BeanUtils.copyProperties(user2, user);
        } catch (IllegalAccessException | InvocationTargetException e) {
            e.printStackTrace();
        }
        System.out.println(user);
        System.out.println(user2);
    }

}

运行结果:

User [id=0, username=张三, age=20, password=null, born=Thu Feb 20 00:00:00 CST 1997, point=Point [x=10, y=12]]
User [id=0, username=张三, age=20, password=null, born=null, point=null]

2.beanUtils封装请求参数

/** * * @param clz,目标类的类型 * @param request，请求 * @return 目标类型的对象 */
    public static Object setParam(Class<?> clz, HttpServletRequest request) {
        Map<String, String[]> paramMap=request.getParameterMap();
        Set<String> strSet=paramMap.keySet();
        Object object=null;
        try {
            object=clz.newInstance();
        } catch (InstantiationException | IllegalAccessException e) {
            e.printStackTrace();
        }
        for(String str: strSet) {
            LogUtil.printLog(str+": "+paramMap.get(str)[0]+" |"+object);
            try {
                String[] paramValue=paramMap.get(str);
                if(paramValue.length>1) {
                    BeanUtils.setProperty(object, str, paramValue);
                }else {
                    BeanUtils.setProperty(object, str, paramValue[0]);
                }
            } catch (IllegalAccessException | InvocationTargetException e) {
                e.printStackTrace();
            }
        }
        return object;
    }