springMVC的参数检验

    
      javax.validation
      validation-api
      1.1.0.Final
    
    
      org.hibernate
      hibernate-validator
      5.2.4.Final
    

    
    
      commons-collections
      commons-collections
      3.2.2
    
    
      commons-codec
      commons-codec
      1.10
    

package com.mmall.util;

import com.google.common.base.Preconditions;
import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
import com.mmall.exception.ParamException;
import org.apache.commons.collections.MapUtils;

import javax.validation.ConstraintViolation;
import javax.validation.Validation;
import javax.validation.Validator;
import javax.validation.ValidatorFactory;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;

public class BeanValidator {

    private static ValidatorFactory validatorFactory = Validation.buildDefaultValidatorFactory();

    //检查一个object对象
    public static  Map validate(T t, Class... groups) {
        Validator validator = validatorFactory.getValidator();
        Set validateResult = validator.validate(t, groups);
        if (validateResult.isEmpty()) {
            return Collections.emptyMap();
        } else {
            LinkedHashMap errors = Maps.newLinkedHashMap();
            Iterator iterator = validateResult.iterator();
            while (iterator.hasNext()) {
                ConstraintViolation violation = (ConstraintViolation)iterator.next();
                errors.put(violation.getPropertyPath().toString(), violation.getMessage());
            }
            return errors;
        }
    }
    //检查一个list对象
    public static Map validateList(Collection collection) {
        Preconditions.checkNotNull(collection);
        Iterator iterator = collection.iterator();
        Map errors;

        do {
            if (!iterator.hasNext()) {
                return Collections.emptyMap();
            }
            Object object = iterator.next();
            errors = validate(object, new Class[0]);
        } while (errors.isEmpty());

        return errors;
    }
    //用一个方法来封装上面的两个方法。我们可以选择用这个方法，然后到map，把map的错误信息记录到日志，再抛异常
    public static Map validateObject(Object first, Object... objects) {
        if (objects != null && objects.length > 0) {
            return validateList(Lists.asList(first, objects));
        } else {
            return validate(first, new Class[0]);
        }
    }
    //我们也可以选择用这个方法，直接抛异常
    public static void check(Object param) throws ParamException {
        Map map = BeanValidator.validateObject(param);
        if (MapUtils.isNotEmpty(map)) {
            throw new ParamException(map.toString());
        }
    }
}

package com.mmall.model;

import lombok.Data;
import org.hibernate.validator.constraints.NotBlank;

import javax.validation.constraints.NotNull;

/**
 * Created by 敲代码的卡卡罗特
 * on 2018/3/24 23:59.
 */
@Data
public class TestVo {
    @NotNull
    private Integer id;
    @NotBlank
    private String name;

    public TestVo(Integer id, String name) {
        this.id = id;
        this.name = name;
    }
}

 @RequestMapping("test.json")
    public ModelAndView ss(){
        BeanValidator.check(new TestVo(null,null));
        HashMap map = new HashMap();
        map.put("name","lzh");
        map.put("age",12);
        ModelAndView view=new ModelAndView("jsonView",map);
        return view;
    }