SpringMVC之绑定参数的类型转换(Date/Double)

一、使用注解式控制器注册PropertyEditor(针对具体的controller类处理)

        1、使用WebDataBinder进行控制器级别的注册PropertyEditor(控制器独享)

 @InitBinder
 // 此处的参数也可以是ServletRequestDataBinder类型
 public void initBinder(WebDataBinder binder) throws Exception {
     // 注册自定义的属性编辑器
     // 1、日期
     DateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
     //CustomDateEditor类是系统内部自带的类
     CustomDateEditor dateEditor = new CustomDateEditor(df, true);
     // 表示如果命令对象有Date类型的属性，将使用该属性编辑器进行类型转换
     binder.registerCustomEditor(Date.class, dateEditor);
     // 自定义的电话号码编辑器(和【4.16.1、数据类型转换】一样)
     binder.registerCustomEditor(PhoneNumberModel.class, new PhoneNumberEditor());
 }

 

        备注：转换对象必须要实现PropertyEditor接口，例如CustomDateEditor类

 

 package org.springframework.beans.propertyeditors;

 import java.beans.PropertyEditorSupport;
 import java.text.DateFormat;
 import java.text.ParseException;
 import java.util.Date;
 import org.springframework.util.StringUtils;

 public class CustomDateEditor extends PropertyEditorSupport {

     private final DateFormat dateFormat;
     private final boolean allowEmpty;
     private final int exactDateLength;

     public CustomDateEditor(DateFormat dateFormat, boolean allowEmpty) {
         this.dateFormat = dateFormat;
         this.allowEmpty = allowEmpty;
         exactDateLength = -1;
     }

     public CustomDateEditor(DateFormat dateFormat, boolean allowEmpty, int exactDateLength) {
         this.dateFormat = dateFormat;
         this.allowEmpty = allowEmpty;
         this.exactDateLength = exactDateLength;
     }

     public void setAsText(String text) throws IllegalArgumentException {
         if (allowEmpty && !StringUtils.hasText(text)) {
             setValue(null);
         } else {
             if (text != null && exactDateLength >= 0 && text.length() != exactDateLength)
                 throw new IllegalArgumentException((new StringBuilder("Could not parse date: it is not exactly")).append(exactDateLength).append("characters long").toString());
             try {
                 setValue(dateFormat.parse(text));
             } catch (ParseException ex) {
                 throw new IllegalArgumentException((new StringBuilder("Could not parse date: ")).append(ex.getMessage()).toString(), ex);
             }
         }
     }

     public String getAsText() {
         Date value = (Date) getValue();
         return value == null ? "" : dateFormat.format(value);
     }

 }

 

二、使用xml配置实现类型转换(系统全局转换器)

     （1）注册ConversionService实现和自定义的类型转换器 

 <!-- ①注册ConversionService -->
 <bean id="conversionService" class="org.springframework.format.support.FormattingConversionServiceFactoryBean">
     <property name="converters">
        <list>
             <bean class="hb.base.convert.DateConverter">
                 <constructor-arg value="yyyy-MM-dd"/>
             </bean>
         </list>
     </property>
     <!-- 格式化显示的配置
     <property name="formatters">
         <list>
             <bean class="hb.base.convert.DateFormatter">
                 <constructor-arg value="yyyy-MM-dd"/>
             </bean>
         </list>
     </property>
 -->
 </bean>

 

    （2）使用 ConfigurableWebBindingInitializer 注册conversionService

 <!-- ②使用 ConfigurableWebBindingInitializer 注册conversionService -->
 <bean id="webBindingInitializer"
     class="org.springframework.web.bind.support.ConfigurableWebBindingInitializer">
     <property name="conversionService" ref="conversionService" />
     <property name="validator" ref="validator" />
 </bean>

 

    （3）注册ConfigurableWebBindingInitializer 到RequestMappingHandlerAdapter

 <!--Spring3.1开始的注解 HandlerAdapter -->
 <bean
     class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter">
     <!--线程安全的访问session -->
     <property name="synchronizeOnSession" value="true" />
     <property name="webBindingInitializer" ref="webBindingInitializer"/>
 </bean>

 

       此时可能有人会问，如果我同时使用 PropertyEditor 和 ConversionService，执行顺序是什么呢？内部首先查找PropertyEditor 进行类型转换，如果没有找到相应的 PropertyEditor 再通过 ConversionService进行转换。

三、直接重写WebBindingInitializer（系统全局转换器）

      （1）实现WebBindingInitializer接口

package org.nercita.core.web.springmvc;

import java.math.BigDecimal;
import java.math.BigInteger;
import java.text.SimpleDateFormat;
import java.util.Date;

import org.springframework.beans.PropertyEditorRegistrar;
import org.springframework.beans.propertyeditors.CustomDateEditor;
import org.springframework.beans.propertyeditors.CustomNumberEditor;
import org.springframework.beans.propertyeditors.StringTrimmerEditor;
import org.springframework.core.convert.ConversionService;
import org.springframework.validation.BindingErrorProcessor;
import org.springframework.validation.MessageCodesResolver;
import org.springframework.validation.Validator;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.bind.support.WebBindingInitializer;
import org.springframework.web.context.request.WebRequest;

/**
 * Created by IntelliJ IDEA.
 * Date:
 * Time: 下午2:50.
 */
public class CustomBindInitializer implements WebBindingInitializer {
    private String format = "yyyy-MM-dd";

    private boolean autoGrowNestedPaths = true;

    private boolean directFieldAccess = false;

    private MessageCodesResolver messageCodesResolver;

    private BindingErrorProcessor bindingErrorProcessor;

    private Validator validator;

    private ConversionService conversionService;

    private PropertyEditorRegistrar[] propertyEditorRegistrars;

    public void setAutoGrowNestedPaths(boolean autoGrowNestedPaths) {
        this.autoGrowNestedPaths = autoGrowNestedPaths;
    }

    public boolean isAutoGrowNestedPaths() {
        return this.autoGrowNestedPaths;
    }

    public final void setDirectFieldAccess(boolean directFieldAccess) {
        this.directFieldAccess = directFieldAccess;
    }

    public boolean isDirectFieldAccess() {
        return directFieldAccess;
    }

    public final void setMessageCodesResolver(MessageCodesResolver messageCodesResolver) {
        this.messageCodesResolver = messageCodesResolver;
    }

    public final MessageCodesResolver getMessageCodesResolver() {
        return this.messageCodesResolver;
    }

    public final void setBindingErrorProcessor(BindingErrorProcessor bindingErrorProcessor) {
        this.bindingErrorProcessor = bindingErrorProcessor;
    }

    public final BindingErrorProcessor getBindingErrorProcessor() {
        return this.bindingErrorProcessor;
    }

    public final void setValidator(Validator validator) {
        this.validator = validator;
    }

    public final Validator getValidator() {
        return this.validator;
    }

    public final void setConversionService(ConversionService conversionService) {
        this.conversionService = conversionService;
    }

    public final ConversionService getConversionService() {
        return this.conversionService;
    }

    public final void setPropertyEditorRegistrar(PropertyEditorRegistrar propertyEditorRegistrar) {
        this.propertyEditorRegistrars = new PropertyEditorRegistrar[]{propertyEditorRegistrar};
    }

    public final void setPropertyEditorRegistrars(PropertyEditorRegistrar[] propertyEditorRegistrars) {
        this.propertyEditorRegistrars = propertyEditorRegistrars;
    }

    public final PropertyEditorRegistrar[] getPropertyEditorRegistrars() {
        return this.propertyEditorRegistrars;
    }


    public void initBinder(WebDataBinder binder, WebRequest request) {
        binder.setAutoGrowNestedPaths(this.autoGrowNestedPaths);
        SimpleDateFormat sf = new SimpleDateFormat(format);
        sf.setLenient(false);
        binder.registerCustomEditor(Date.class, new CustomDateEditor(sf, true));
        binder.registerCustomEditor(String.class, new StringTrimmerEditor(false));
        binder.registerCustomEditor(Short.class, new CustomNumberEditor(Short.class, true));
        binder.registerCustomEditor(Integer.class, new CustomNumberEditor(Integer.class, true));
        binder.registerCustomEditor(Long.class, new CustomNumberEditor(Long.class, true));
        binder.registerCustomEditor(Float.class, new CustomNumberEditor(Float.class, true));
        binder.registerCustomEditor(Double.class, new CustomNumberEditor(Double.class, true));
        binder.registerCustomEditor(BigDecimal.class, new CustomNumberEditor(BigDecimal.class, true));
        binder.registerCustomEditor(BigInteger.class, new CustomNumberEditor(BigInteger.class, true));
        if (this.directFieldAccess) {
            binder.initDirectFieldAccess();
        }
        if (this.messageCodesResolver != null) {
            binder.setMessageCodesResolver(this.messageCodesResolver);
        }
        if (this.bindingErrorProcessor != null) {
            binder.setBindingErrorProcessor(this.bindingErrorProcessor);
        }
        if ((this.validator != null) && (binder.getTarget() != null) &&
                (this.validator.supports(binder.getTarget().getClass()))) {
            binder.setValidator(this.validator);
        }
        if (this.conversionService != null) {
            binder.setConversionService(this.conversionService);
        }
        if (this.propertyEditorRegistrars != null)
            for (PropertyEditorRegistrar propertyEditorRegistrar : this.propertyEditorRegistrars)
                propertyEditorRegistrar.registerCustomEditors(binder);
    }

    public void setFormat(String format) {
        this.format = format;
    }
}

      （2）xml配置

	<bean id="handlerAdapter"  class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">	
		<property name="messageConverters">
			<list>
				<bean class="org.nercita.core.web.springmvc.StringHttpMessageConverter" />
				<ref bean="msgConverter"/>
			</list>
		</property>
		<property name="webBindingInitializer">
			<bean class="org.nercita.core.web.springmvc.CustomBindInitializer">		   
				 
				<property name="validator" ref="validator" />
				<property name="conversionService" ref="conversionService" /> 
			</bean> 
		</property>
	</bean>