Json字符串与Object、List、Map的互转工具类

package com.cq2022.zago.base.util;

import java.io.filereader;

import java.io.filewriter;

import java.io.ioexception;

import java.io.stringwriter;

import java.util.list;

import java.util.map;

import org.codehaus.jackson.jsonfactory;

import org.codehaus.jackson.jsongenerationexception;

import org.codehaus.jackson.jsongenerator;

import org.codehaus.jackson.jsonnode;

import org.codehaus.jackson.jsonparseexception;

import org.codehaus.jackson.map.jsonmappingexception;

import org.codehaus.jackson.map.objectmapper;

import org.codehaus.jackson.map.serializationconfig;

import org.codehaus.jackson.map.annotate.jsonserialize;

import com.alibaba.fastjson.jsonarray;

/**

  * json工具类，实现json与java bean的互相转换

  */

public class jsonutils {

  private static objectmapper objectmapper = new objectmapper();

  private static jsonfactory jsonfactory = new jsonfactory();

  static {

  objectmapper.configure(serializationconfig.feature.write_null_map_values, false );

  objectmapper.setserializationinclusion(jsonserialize.inclusion.non_null);

  }

  /**

  * 泛型返回，json字符串转对象

  * @param jsonasstring

  * @param pojoclass

  * @return

  * @throws jsonmappingexception

  * @throws jsonparseexception

  * @throws ioexception

  */

  public static <t> t fromjson(string jsonasstring, class <t> pojoclass) throws jsonmappingexception,

   jsonparseexception, ioexception {

  return objectmapper.readvalue(jsonasstring, pojoclass);

  }

  public static <t> t fromjson(filereader fr, class <t> pojoclass) throws jsonparseexception, ioexception {

  return objectmapper.readvalue(fr, pojoclass);

  }

  /**

  * object对象转json

  * @param pojo

  * @return

  * @throws jsonmappingexception

  * @throws jsongenerationexception

  * @throws ioexception

  */

  public static string tojson(object pojo) throws jsonmappingexception, jsongenerationexception, ioexception {

  return tojson(pojo, false );

  }

  public static string tojson(object pojo, boolean prettyprint) throws jsonmappingexception, jsongenerationexception,

   ioexception {

  stringwriter sw = new stringwriter();

  jsongenerator jg = jsonfactory.createjsongenerator(sw);

  if (prettyprint) {

   jg.usedefaultprettyprinter();

  }

  objectmapper.writevalue(jg, pojo);

  return sw.tostring();

  }

  public static void tojson(object pojo, filewriter fw, boolean prettyprint) throws jsonmappingexception,

   jsongenerationexception, ioexception {

  jsongenerator jg = jsonfactory.createjsongenerator(fw);

  if (prettyprint) {

   jg.usedefaultprettyprinter();

  }

  objectmapper.writevalue(jg, pojo);

  }

  /**

  * json字符串转map

  * @param jsonstr

  * @return

  * @throws ioexception

  */

  public static map<string, object> parsemap(string jsonstr) throws ioexception {

  map<string, object> map = objectmapper.readvalue(jsonstr, map. class );

  return map;

  }

  public static jsonnode parse(string jsonstr) throws ioexception {

  jsonnode node = null ;

  node = objectmapper.readtree(jsonstr);

  return node;

  }

  public static objectmapper getobjectmapper() {

  return objectmapper;

  }

  /**

  * json字符串转 list对象

  * @param str json字符串

  * @param clazz 转换的类型

  * @return

  */

  public static <t> list<t> fromlistjson(string str, class <t> clazz){

  return jsonarray.parsearray(str, clazz);

  }

}