Request To JavaBean(请求对象转换为JavaBean对象)

背景: 
经常要从request等对象取出值来赋入bean中,如果不用MVC框架的绑定功能的话,麻烦  
一 参考资料 
http://jc-dreaming.iteye.com/blog/563893 
http://www.iteye.com/topic/76043 
http://xubindehao.iteye.com/blog/754807 
http://javafenger.iteye.com/blog/96829 
http://www.kaila.com.cn/space.php?uid=7114&do=blog&id=458578 
http://blog.csdn.net/zsx923/archive/2010/01/19/5210325.aspx 
二 代码示例 

Java代码
import java.beans.IntrospectionException;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Enumeration;
import javax.servlet.http.HttpServletRequest;
import org.apache.commons.beanutils.BeanUtils;

public class RequestToBean {
	
	/**
	 * ConvertUtilsBean convertUtils = new ConvertUtilsBean();   
	 * DateConverter dateConverter = new DateConverter();   
	 * convertUtils.register(dateConverter,Date.class);    
	 * */
	
	
	/**
	 * @param <T>
	 * @param newSource  现将要设置新值的对象
	 * @param source     源数据对象
	 */
	public static <T> void  beanConvert(T newSource,T source){
		try {
			BeanUtils.copyProperties(newSource,source);
		} catch (IllegalAccessException e) {			
			e.printStackTrace();
		} catch (InvocationTargetException e) {			
			e.printStackTrace();
		} 
	}
	
	/**
	 * @param request 请求对象
	 * @param obj     要设置Bean的类型,传入试为: Bean.class
	 * @return
	 */
	@SuppressWarnings("unchecked")	
	public static <T> T getBeanToRequest(HttpServletRequest request,Class<T> clazz){  
		
		//获取页面所有的请求参数名称
        Enumeration<String> enume = request.getParameterNames();   
		T beanObj = getObjectByClass(clazz);
        try{   
            while(enume.hasMoreElements()){   
            	//参数名称
                String propertyName = enume.nextElement();                
                //判断是否存在此属性
                if(isCheckBeanExitsPropertyName(clazz,propertyName)){
                	//获取请求值
                	Object propertyValue = request.getParameter(propertyName);
                	setProperties(beanObj,propertyName,propertyValue);
                }
                
            }   
        }catch(Exception e){}  
           
        return beanObj;   
    }  
	
	private static <T> T getObjectByClass(Class<T> clazz){
		T t = null;
		try {
			t = clazz.newInstance();
		} catch (InstantiationException e1) {			
			e1.printStackTrace();
		} catch (IllegalAccessException e1) {			
			e1.printStackTrace();
		}
		return t;
	}
	
	
	
	/**
	 * @param clazz           Class对象
	 * @param propertyName    属性名称
	 * @return true || false  检查对象中是否存在该属性名称
	 */
	private  static boolean isCheckBeanExitsPropertyName(Class<?> clazz,String propertyName){	
		boolean retValue = false;
		try {
			Field field =  clazz.getDeclaredField(propertyName);			
			if(null != field){
				retValue = true;
			}
		} catch (NoSuchFieldException e) {			
			Out.println("类: " + clazz.getSimpleName()+",不存在属性名: "+propertyName+" ,详细错误信息: "+e.getMessage());		
		}
		return retValue;
		
	}
	
	 /**  
     * 设置字段值      
     * @param obj          实例对象  
     * @param propertyName 属性名  
     * @param value        新的字段值  
     * @return            
     */   
    public static void setProperties(Object object, String propertyName,Object value) throws IntrospectionException,   
            IllegalAccessException, InvocationTargetException {   
        PropertyDescriptor pd = new PropertyDescriptor(propertyName,object.getClass());   
        Method methodSet = pd.getWriteMethod();   
        methodSet.invoke(object,value);   
    }         
}

  三 使用common beanutils组件 
代码: 
User user = new User(); 
BeanUtils.populate(user,request.getParameterMap()); 

原文地址:https://www.cnblogs.com/a757956132/p/4649497.html