JSON 之FastJson解析

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 一、阿里巴巴FastJson是一个Json处理工具包，包括“序列化”和“反序列化”两部分，它具备如下特征：
速度最快，测试表明，fastjson具有极快的性能，超越任其他的Java Json parser。包括自称最快的JackJson；
功能强大，完全支持Java Bean、集合、Map、日期、Enum，支持范型，支持自省；无依赖，能够直接运行在Java SE 5.0以上版本；支持Android；开源 (Apache 2.0)

二、FastJson解析JSON步骤
 

然后将数据转为json字符串，核心函数是：
public static String createJsonString(Object value)
    {
        String alibabaJson = JSON.toJSONString(value);
        return alibabaJson;
    }
B、客户端将json字符串转换为相应的javaBean
  首先客户端也要导入fastjson的两个jar包
1、客户端获取json字符串
public class HttpUtil
{
   
    public static String getJsonContent(String urlStr)
    {
        try
        {// 获取HttpURLConnection连接对象
            URL url = new URL(urlStr);
            HttpURLConnection httpConn = (HttpURLConnection) url
                    .openConnection();
            // 设置连接属性
            httpConn.setConnectTimeout(3000);
            httpConn.setDoInput(true);
            httpConn.setRequestMethod("GET");
            // 获取相应码
            int respCode = httpConn.getResponseCode();
            if (respCode == 200)
            {
                return ConvertStream2Json(httpConn.getInputStream());
            }
        }
        catch (MalformedURLException e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        catch (IOException e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return "";
    }

   
    private static String ConvertStream2Json(InputStream inputStream)
    {
        String jsonStr = "";
        // ByteArrayOutputStream相当于内存输出流
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int len = 0;
        // 将输入流转移到内存输出流中
        try
        {
            while ((len = inputStream.read(buffer, 0, buffer.length)) != -1)
            {
                out.write(buffer, 0, len);
            }
            // 将内存流转换为字符串
            jsonStr = new String(out.toByteArray());
        }
        catch (IOException e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return jsonStr;
    }
}
2、使用泛型获取javaBean（核心函数）
    public static T getPerson(String jsonString, Class cls) {
        T t = null;
        try {
            t = JSON.parseObject(jsonString, cls);
        } catch (Exception e) {
            // TODO: handle exception
        }
        return t;
    }
public static List getPersons(String jsonString, Class cls) {
        List list = new ArrayList();
        try {
            list = JSON.parseArray(jsonString, cls);
        } catch (Exception e) {
        }
        return list;
    }
public static List> listKeyMaps(String jsonString) {
        List> list = new ArrayList>();
        try {
            list = JSON.parseObject(jsonString,
                    new TypeReference>>() {
            });
        } catch (Exception e) {
            // TODO: handle exception
        }
        return list;
    }

http://blog.sina.com.cn/s/blog_7ffb8dd501013qas.html

JSON 之FastJson解析

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原文地址：http://www.cnblogs.com/cmblogs/p/4333234.html