爱威尔-fastjson + spring mvc 对ORM框架(hibernate，jpa)多对一等关系循环引用的问题解决

实体的格式：


	@Entity 
@Table(name = "Z_HANDOVER_INFO", schema = "LAUVANYJDBA") 
@DynamicInsert(true) 
@DynamicUpdate(true) 
public class Z_Handover_Info implements java.io.Serializable { 
。。。。。。


	@ManyToOne 
@JoinColumn(name="us_Handid") 
public T_User_Info getUs_Handid() { 
return us_Handid; 
} 
 
public void setUs_Handid(T_User_Info us_Handid) { 
this.us_Handid = us_Handid; 
} 
。。。。。


	}


	在对list<Z_Handover_Info> 返回json 时会出现Object { $ref="$.rows[0].us_Handid"} 这种情况，我的前端UI是easyui。


	解决是在springmvc 的配置中加入：


	<bean id="fastJsonHttpMessageConverter" 
class="com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter"> 
<property name="supportedMediaTypes"> 
 <list> 
                <value>application/json;charset=UTF-8</value> 
            </list> 
</property> 
<property name="features"> 
  <array> 
           <value>DisableCircularReferenceDetect</value> 
          </array> 
        </property> 
   </bean> 
这个功能是在fastjson的包里面：


<pre class="prettyprint lang-java">/*
 * Copyright 1999-2101 Alibaba Group.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.alibaba.fastjson.serializer;

/**
 * @author wenshao[szujobs@hotmail.com]
 */
public enum SerializerFeature {
    QuoteFieldNames,
    /**
     * 
     */
    UseSingleQuotes,
    /**
     * 
     */
    WriteMapNullValue,
    /**
     * 用枚举toString()值输出
     */
    WriteEnumUsingToString,
    /**
     * 用枚举name()输出
     */
    WriteEnumUsingName,
    /**
     * 
     */
    UseISO8601DateFormat,
    /**
     * @since 1.1
     */
    WriteNullListAsEmpty,
    /**
     * @since 1.1
     */
    WriteNullStringAsEmpty,
    /**
     * @since 1.1
     */
    WriteNullNumberAsZero,
    /**
     * @since 1.1
     */
    WriteNullBooleanAsFalse,
    /**
     * @since 1.1
     */
    SkipTransientField,
    /**
     * @since 1.1
     */
    SortField,
    /**
     * @since 1.1.1
     */
    @Deprecated
    WriteTabAsSpecial,
    /**
     * @since 1.1.2
     */
    PrettyFormat,
    /**
     * @since 1.1.2
     */
    WriteClassName,

/**
     * @since 1.1.6
     */
    DisableCircularReferenceDetect,

/**
     * @since 1.1.9
     */
    WriteSlashAsSpecial,

/**
     * @since 1.1.10
     */
    BrowserCompatible,

/**
     * @since 1.1.14
     */
    WriteDateUseDateFormat,

/**
     * @since 1.1.15
     */
    NotWriteRootClassName,

/**
     * @since 1.1.19
     */
    DisableCheckSpecialChar,

/**
     * @since 1.1.35
     */
    BeanToArray,

/**
     * @since 1.1.37
     */
    WriteNonStringKeyAsString,
    
    /**
     * @since 1.1.42
     */
    NotWriteDefaultValue,
    
    /**
     * @since 1.2.6
     */
    BrowserSecure,
    
    /**
     * @since 1.2.7
     */
    IgnoreNonFieldGetter
    ;

SerializerFeature(){
 mask = (1 << ordinal());
 }

private final int mask;

public final int getMask() {
        return mask;
    }

public static boolean isEnabled(int features, SerializerFeature feature) {
        return (features & feature.getMask()) != 0;
    }
    
    public static boolean isEnabled(int features, int fieaturesB, SerializerFeature feature) {
        int mask = feature.getMask();
        
        return (features & mask) != 0 || (fieaturesB & mask) != 0;
    }

public static int config(int features, SerializerFeature feature, boolean state) {
        if (state) {
            features |= feature.getMask();
        } else {
            features &= ~feature.getMask();
        }

return features;
 }
 
 public static int of(SerializerFeature[] features) {
 if (features == null) {
 return 0;
 }
 
 int value = 0;
 
 for (SerializerFeature feature: features) {
 value |= feature.getMask();
 }
 
 return value;
 }
}
</pre>
spring 最新版的，fastjson是1.2.6版本，我看网上其他的都有问题。

fastjson + spring mvc 对ORM框架(hibernate，jpa)多对一等关系 循环引用的问题解决

fastjson + spring mvc 对ORM框架(hibernate，jpa)多对一等关系循环引用的问题解决