解决：Failed to convert value of type ‘java.lang.String‘ to required type ‘java.util.Date‘；

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发生这一错误的主要原因是Controller类中需要接收的是Date类型，但是在页面端传过来的是String类型，最终导致了这个错误。

这里提供两种解决方案，一种是局部转换，一种是全局转换。

<form action="login.do" method="post">
		<input type="text" name="birthday" value="2017-07-12 22:04:00">
		<input type="submit" value="提交">
	</form>

一.局部转换

@Controller
public class UserController{
	
	@RequestMapping(value="/login.do")
	public String login(String username,Date birthday){
		System.out.println("________");
		return "";
	}

        //只需要加上下面这段即可，注意不能忘记注解
	@InitBinder
	public void initBinder(WebDataBinder binder, WebRequest request) {
		
		//转换日期
		DateFormat dateFormat=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
		binder.registerCustomEditor(Date.class, new CustomDateEditor(dateFormat, true));// CustomDateEditor为自定义日期编辑器
	}
}

二.全局转换

1.创建CustomDate类实现WebBindingInitializer

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import org.springframework.beans.propertyeditors.CustomDateEditor;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.bind.support.WebBindingInitializer;
import org.springframework.web.context.request.WebRequest;

/**
 * @作者：JackHisen(GWD)
 * @项目名：shoppingmall
 * @时间：2017-7-12 下午10:39:10
 * @version 1.0
 */
public class CustomDate implements WebBindingInitializer{

	@Override
	public void initBinder(WebDataBinder binder, WebRequest request) {
		// TODO Auto-generated method stub
		//转换日期
		DateFormat dateFormat=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
		binder.registerCustomEditor(Date.class, new CustomDateEditor(dateFormat, true));
	}
}

2.在Spring-MVC.xml中配置日期转换

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
	xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jdbc="http://www.springframework.org/schema/jdbc"
	xmlns:context="http://www.springframework.org/schema/context"
	xsi:schemaLocation="
     http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
     http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
     http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.0.xsd
     http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
     http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd">
	<context:component-scan base-package="com.gwd.shopping" use-default-filters="false">
		<context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
	</context:component-scan>
	
	<!-- 日期转换 -->
	<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
		<property name="webBindingInitializer">
			<bean class="com.gwd.shopping.core.web.CustomDate"/>
		</property>
	</bean>
	
	<bean id="jspViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
		<property name="prefix" value="/WEB-INF/back_page/"/>
		<property name="suffix" value=".jsp"/>
	</bean>
</beans>