通过反射获取常量值

一：通过反射获取常量值，项目中有个需求需要将请求信息封装到javaBean中

但是请求信息比较特殊，需要通过编码去获取，而且编码是定义在接口类中的常量，所以为了方便

特别把这块功能封装起来

1：定义的常量

/**
 * 
 */
package com.hlcui.entity;

/**
 * @author Administrator
 *
 */
public interface ConstantsUtil {
    
    public static interface TeamFundMgr{
        public static final int id = 111;
        public static final String name = "李白";
        public static final double salary = 15000.000;
    }
    
}

2：javaBean类

/**
 * 
 */
package com.hlcui.entity;

/**
 * @author Administrator
 *
 */
public class Person {
    
    private int id;
    
    private String name;
    
    private double salary;
    
    private String mgr;
    
    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public double getSalary() {
        return salary;
    }

    public void setSalary(double salary) {
        this.salary = salary;
    }

    public String getMgr() {
        return mgr;
    }

    public void setMgr(String mgr) {
        this.mgr = mgr;
    }

    public String getName() {
        return name;
    }


    public void setName(String name) {
        this.name = name;
    }

    @Override
    public String toString() {
        return "Person [id=" + id + ", name=" + name + ", salary=" + salary + ", mgr=" + mgr + "]";
    }
    
}

3：转换以及测试方法

/**
 * 
 */
package com.hlcui.test;

import java.beans.BeanInfo;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Field;
import java.lang.reflect.Method;

import com.hlcui.entity.ConstantsUtil;
import com.hlcui.entity.Person;

/**
 * @author Administrator
 *
 */
public class TestOperateConstant {
    
    private static final String EXCLUDE_FIELD = "class";
    
    public static void main(String[] args) throws Exception {
        Person person = toBean(new Person());
        System.out.println(person);
    }
    
    public static <T> T toBean(T t){
        Class<?> clazz = t.getClass();
        try {
            BeanInfo beanInfo = Introspector.getBeanInfo(clazz);
            PropertyDescriptor[] props = beanInfo.getPropertyDescriptors();
            for(PropertyDescriptor property:props){
                String field = property.getName();
                if(EXCLUDE_FIELD.equals(field)){
                    continue;
                }
                Method method = property.getWriteMethod();
                method.invoke(t,getValue(field,ConstantsUtil.TeamFundMgr.class));
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return t;
    }
    
    public static Object getValue(String fieldName,Class<?> clazz)throws Exception{
        Field[] fields = clazz.getDeclaredFields();
        for(Field field:fields){
            String name = field.getName();
            if(fieldName.equals(name)){
                return field.get(clazz);
            }
        }
        return null;
    }
}

4：运行结果

Person [id=111, name=李白, salary=15000.0, mgr=null]