springmvc後臺驗證返回json數據

package cn.microvideo.oa.util;

import org.springframework.validation.BindingResult;
import org.springframework.validation.FieldError;

public class BindResult {
	private BindResult() {
	}
	public static Json Br(BindingResult br, Json json) {
		Json json2=json;
		StringBuffer sb=new StringBuffer();
		//錯誤消息返回
		if (br.hasErrors()) {  
		    for (FieldError fieldError : br.getFieldErrors()) {  
		        sb.append(fieldError.getDefaultMessage()+",");
		    }  
		    json2.setMsg(sb.deleteCharAt(sb.length()-1).toString());
		    json2.setSuccess(false);
		    return json;  
		}
		return json2;
	}
}

這裏把所有錯誤都查詢後返回，控制層方法調用BindResult，另外也可以使用springmvc3.2的新註解ControllerAdvice

package cn.microvideo.oa.util;
/**
 * view object
 * @author wzy
 *
 */
public class Json {

	private boolean success = false;

	private String msg = "";

	private Object obj = null;

	public boolean isSuccess() {
		return success;
	}

	public void setSuccess(boolean success) {
		this.success = success;
	}

	public String getMsg() {
		return msg;
	}

	public void setMsg(String msg) {
		this.msg = msg;
	}

	public Object getObj() {
		return obj;
	}

	public void setObj(Object obj) {
		this.obj = obj;
	}

}

使用3.2的新註解，OAException是自定義異常

package cn.microvideo.oa.controller.exception;

import org.springframework.http.HttpStatus;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.ResponseStatus;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.view.json.MappingJacksonJsonView;
/**
 * 統一異常出口
 * @author wzy
 *
 */
@ControllerAdvice
public class GlobalExceptionHandler {
		private MappingJacksonJsonView  jsonView = new MappingJacksonJsonView();
	    @ExceptionHandler({OAException.class})
	    @ResponseStatus(HttpStatus.UNAUTHORIZED)
	    @ResponseBody
	    public ModelAndView  processOAException(NativeWebRequest request, OAException e) {
	    	 return new ModelAndView(jsonView,"msg",e.getMessage());
	    }
}

<context:component-scan base-package="cn.microvideo.oa" use-default-filters="false">
		<context:include-filter type="annotation" expression="org.springframework.stereotype.Controller" />
		<context:include-filter type="annotation" expression="org.springframework.web.bind.annotation.ControllerAdvice" />
	</context:component-scan>

參考
http://www.tuicool.com/articles/iYfqeq

http://json20080301.iteye.com/blog/1876488

http://jackyrong.iteye.com/blog/1844080