对象如何转json字符串数组 java 对象转json格式的字符串

package facadeTest.jsonTest;

import junit.framework.TestCase;
import net.sf.json.JSONArray;
import com.alibaba.fastjson.JSONObject;
import com.paic.pa18shop.auto.dto.common.QueryOrderParameterDTO;

/**
 * 将对象转换成json字符串的几种方式 toJSONString使用的是import com.alibaba.fastjson.JSONObject
 * jar包 JSONArray import net.sf.json.JSONArray
 */
public class JsonTest extends TestCase {
	public void test() {
		QueryOrderParameterDTO queryOrderParameterDTO = new QueryOrderParameterDTO();
		queryOrderParameterDTO.setPolicyNo("sorry");
		queryOrderParameterDTO.setProductCode("C01");
		queryOrderParameterDTO.setSeriesNo("03");
		// 获取queryOrderParaneterDTO对象
		System.out.println(queryOrderParameterDTO);
		// 获取set到queryOrderParaneterDTO对象中的值得json字符串
		JSONObject json = new JSONObject();
		String query = json.toJSONString(queryOrderParameterDTO);
		System.out.println(query);
		// 获取queryOrderParaneterDTO对象的json字符串
		JSONArray js = JSONArray.fromObject(queryOrderParameterDTO);
		String array = js.toString();
		System.out.println(array);
	}
}