实时汇率转换

梦里梦外; 2022-06-15 04:57 163阅读 0赞

## 最近公司业务需要外汇转换，这里记录下汇率实时更新的处理方式 ##

1.  申请汇率API接口（这里用的是聚合数据的API，免费每天调用100次）
2.  编程用到的语言（网站上有对应的基本测试代码）
3.  新建测试项目，导入所需jar包（Myeclipse）
4.  根据需求更改代码
5.  调用成功（大功告成）  
    代码贴出来：

package com.goldatg.util;
    
    import java.io.BufferedReader;
    import java.io.DataOutputStream;
    import java.io.IOException;
    import java.io.InputStream;
    import java.io.InputStreamReader;
    import java.io.UnsupportedEncodingException;
    import java.net.HttpURLConnection;
    import java.net.URL;
    import java.net.URLEncoder;
    import java.util.HashMap;
    import java.util.Map;
    
    import net.sf.json.JSONArray;
    import net.sf.json.JSONObject;
    /**
     * 
     * @项目名称:@{project_name}
     * @类名称:@{type_name}
     * @类描述:
     * @创建人:{user}
     * @创建时间:2017-5-24下午4:02:35
     * 
     * @修改人:
     * @修改时间:2017-5-24下午4:02:35
     * @修改备注:
     * @version:
     */
    public class ExchangeUtil {
        public static final String DEF_CHATSET = "UTF-8";
        public static final int DEF_CONN_TIMEOUT = 30000;
        public static final int DEF_READ_TIMEOUT = 30000;
        public static String userAgent =  "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/29.0.1547.66 Safari/537.36";
    
        //配置您申请的KEY
        public static final String APPKEY ="*****************";
    
        //1.常用汇率查询
        public static void getRequestExchange(){
            String result =null;
            String url ="http://op.juhe.cn/onebox/exchange/query";//请求接口地址
            Map params = new HashMap();//请求参数
                params.put("key",APPKEY);//应用APPKEY(应用详细页查询)
    
            try {
                result =net(url, params, "GET");
                JSONObject object = JSONObject.fromObject(result);
                if(object.getInt("error_code")==0){
                    System.out.println(object.get("result"));
                }else{
                    System.out.println(object.get("error_code")+":"+object.get("reason"));
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    
        //2.货币列表
        public static String getRequestCurrencyList(){
            String result =null;
            String url ="http://op.juhe.cn/onebox/exchange/list";//请求接口地址
            String currencyList = null;//货币列表
            Map params = new HashMap();//请求参数
                params.put("key",APPKEY);//应用APPKEY(应用详细页查询)
    
            try {
                result =net(url, params, "GET");
                JSONObject object = JSONObject.fromObject(result);
                if(object.getInt("error_code")==0){
                    System.out.println(object.get("result"));
                    currencyList = object.get("result").toString();
                }else{
                    System.out.println(object.get("error_code")+":"+object.get("reason"));
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
            return currencyList;
        }
    
        //3.实时汇率查询换算
        public static String getRequestConversion(String currency){
            String result =null;
            String url ="http://op.juhe.cn/onebox/exchange/currency";//请求接口地址
            String multiple = null;//转换后得到的倍数
            Map params = new HashMap();//请求参数
                params.put("from","USD");//转换汇率前的货币代码
                params.put("to",currency);//转换汇率成的货币代码
                params.put("key",APPKEY);//应用APPKEY(应用详细页查询)
    
            try {
                result =net(url, params, "GET");
                JSONObject object = JSONObject.fromObject(result);//得到当前返回的结果
                String str = object.get("result").toString();//根据键“result”得到值
                JSONArray objArray = JSONArray.fromObject(str);//转换成JSON数组对象
                multiple = (String) objArray.getJSONObject(0).get("result");//得到精确值
                if(object.getInt("error_code")==0){
                    System.out.println(object.get("result"));
                    System.out.println(multiple);
                }else{
                    System.out.println(object.get("error_code")+":"+object.get("reason"));
    
                }
            } catch (Exception e) {
                e.printStackTrace(); 
            }
            return multiple;
        }
    
    
    
        public static void main(String[] args) {
    
        }
    
        /**
         *
         * @param strUrl 请求地址
         * @param params 请求参数
         * @param method 请求方法
         * @return  网络请求字符串
         * @throws Exception
         */
        public static String net(String strUrl, Map params,String method) throws Exception {
            HttpURLConnection conn = null;
            BufferedReader reader = null;
            String rs = null;
            try {
                StringBuffer sb = new StringBuffer();
                if(method==null || method.equals("GET")){
                    strUrl = strUrl+"?"+urlencode(params);
                }
                URL url = new URL(strUrl);
                conn = (HttpURLConnection) url.openConnection();
                if(method==null || method.equals("GET")){
                    conn.setRequestMethod("GET");
                }else{
                    conn.setRequestMethod("POST");
                    conn.setDoOutput(true);
                }
                conn.setRequestProperty("User-agent", userAgent);
                conn.setUseCaches(false);
                conn.setConnectTimeout(DEF_CONN_TIMEOUT);
                conn.setReadTimeout(DEF_READ_TIMEOUT);
                conn.setInstanceFollowRedirects(false);
                conn.connect();
                if (params!= null && method.equals("POST")) {
                    try {
                        DataOutputStream out = new DataOutputStream(conn.getOutputStream());
                            out.writeBytes(urlencode(params));
                    } catch (Exception e) {
                        // TODO: handle exception
                    }
                }
                InputStream is = conn.getInputStream();
                reader = new BufferedReader(new InputStreamReader(is, DEF_CHATSET));
                String strRead = null;
                while ((strRead = reader.readLine()) != null) {
                    sb.append(strRead);
                }
                rs = sb.toString();
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                if (reader != null) {
                    reader.close();
                }
                if (conn != null) {
                    conn.disconnect();
                }
            }
            return rs;
        }
    
        //将map型转为请求参数型
        public static String urlencode(Map<String,Object>data) {
            StringBuilder sb = new StringBuilder();
            for (Map.Entry i : data.entrySet()) {
                try {
                    sb.append(i.getKey()).append("=").append(URLEncoder.encode(i.getValue()+"","UTF-8")).append("&");
                } catch (UnsupportedEncodingException e) {
                    e.printStackTrace();
                }
            }
            return sb.toString();
        }
    }

这里要注意的是：这里针对的是web项目，如要测试请新建一个Servlet在浏览器进行访问，控制台输出，得到的结果是JSONObject对象，根据不同的需求，进行分解转化java对象；  
JSONObject所需6个jar包，如有需要点击这里可以免费下载[http://download.csdn.net/detail/qq\_33624284/9851046][http_download.csdn.net_detail_qq_33624284_9851046]

[http_download.csdn.net_detail_qq_33624284_9851046]: http://download.csdn.net/detail/qq_33624284/9851046