struts2中 jsp页面 空文本框传值 及action层不同类型的判断

struts2可以自动转换jsp前台传来的信息格式

前台jsp

</pre><pre name="code" class="html"><form action="user_setInfo" method="post">
  名字<input type="text" value="" name="name"/><br/>
  日期<input type="text" value="" name="date"/><br/>
  年龄<input type="text" value="" name="age"/><br/>
  颜色1<input type="text" value="" name="color"/><br/>
  颜色2<input type="text" value="" name="color"/><br/>
 尺寸1 <input type="text" value="" name="size"/><br/>
  尺寸2<input type="text" value="" name="size"/><br/>
  <input type="submit" value="提交"/>
  </form>

后台action

package action;

import java.util.Date;
import java.util.List;

import javax.servlet.http.HttpServletRequest;

import org.apache.struts2.ServletActionContext;

import com.opensymphony.xwork2.ActionSupport;



public class UserAction extends ActionSupport{
	
	/**
	 * 952740499
	 */
	private static final long serialVersionUID = 1L;

	private String name;
	private Date date;
	private List<String> color;
	private String [] size;
	private int age;
	public String setInfo() {
		
		System.out.println("名字*****"+name);
		System.out.println("日期*****"+date);
		System.out.println("颜色*****"+color.get(0)+"*****"+color.get(1));
		System.out.println("尺寸*****"+size[0]+"****"+size[1]);
		System.out.println("年龄******"+age);
		
		return "info";
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public Date getDate() {
		return date;
	}
	public void setDate(Date date) {
		this.date = date;
	}
	public List<String> getColor() {
		return color;
	}
	public void setColor(List<String> color) {
		this.color = color;
	}

	public String[] getSize() {
		return size;
	}
	public void setSize(String[] size) {
		this.size = size;
	}
	public int getAge() {
		return age;
	}
	public void setAge(int age) {
		this.age = age;
	}
	

}

</pre><pre name="code" class="java">提交后输出

</pre><pre name="code" class="java"><img src="http://img.blog.csdn.net/20151107124451402?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQv/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center" alt="" />

1.当前台jsp中 input 的那么中 没有后台action的属性名，除int类型外 则接受到判断用 xx==null，int类型用xx==0

2 . 当name和action中属性名匹配时

	<span style="color:#ff0000;">//为对象（除Object外）时用xx==null
	//当为String或Object时用xx.equls("")
	//当为int时用 xx==0</span>
	private String name;
	private Date date;//date==null
	private List<String> color;//color.get(0).equals("")
	private Object [] size;//oject 使用equals("")
	private int age;//age==0
	public String setInfo() {
		
		System.out.println("名字*****"+name.equals(""));
		System.out.println(date==null);
		System.out.println(color.get(0).equals(""));
		System.out.println("颜色"+color);
		System.out.println(size[0].equals(""));
		System.out.println("大小"+size);
		System.out.println(age==0);
		
		return "info";
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public Date getDate() {
		return date;
	}
	public void setDate(Date date) {
		System.out.println("ddddddddddddddddddd");//虽然date为null但是会调用
		this.date = date;
	}
	public List<String> getColor() {
		return color;
	}
	public void setColor(List<String> color) {
		this.color = color;
	}

	
	
	
	public Object[] getSize() {
		return size;
	}
	public void setSize(Object[] size) {
		this.size = size;
	}
	public int getAge() {
		return age;
	}
	public void setAge(int age) {
		this.age = age;
	}