今天项目组小弟居然问我怎么用java访问特定的地址获取数据和发送请求
Http请求都是通过输入输出流来进行操作的,首先要制定GET或者POST,默认是GET,在安全和数据量较大情况下请使用post
根据url建立链接,读取输入输出流,从中取得相应的返回数据,
http是无序的,在安全性极高的地方请使用https,但是https传输效率差不多只是http的1/10,所以除非特别必要,请谨慎选择
我将我以前写的微信开发代码贴一部分出来,这里就有根据地址获取请求数据和向某一个特定端口发送数据
package com.xiao.weixin.service.impl; import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.security.MessageDigest;
import java.util.Arrays;
import java.util.Date;
import java.util.HashMap;
import java.util.Map; import javax.annotation.Resource; import org.json.JSONObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service; import com.xiao.weixin.common.jdbc.DataSource;
import com.xiao.weixin.dao.WeixinApiMapper;
import com.xiao.weixin.entity.AccessToken;
import com.xiao.weixin.service.WeixinApiService;
import com.xiao.weixin.utils.ApiUrl;
import com.xiao.weixin.utils.CommonUtil;
import com.xiao.weixin.utils.DateUtil; @Service(value = "weixinApiService")
public class WeixinApiServiceImpl implements WeixinApiService { private Logger log = LoggerFactory.getLogger(WeixinApiServiceImpl.class); @Value("${weixin.appID}")
private String appID; @Value("${weixin.appsecret}")
private String appsecret; @Value("${weixin.menu}")
private String menuString; @Value("${weixin.token}")
private String weixinToken; @Resource
private WeixinApiMapper weixinApiMapper; @Override
@DataSource
public String getAccessToken() {
String access_token = null;
try {
AccessToken token = weixinApiMapper.findToken();// 数据库查找没过期的token并返回
if (token != null) {
access_token = token.getAccessToken();
}
} catch (Exception e) {
log.error("获取accessToken出错");
e.printStackTrace();
}
log.debug("获取到的accessToken是:" + access_token);
return access_token;
} @Override
public void refreshAccessToken() {
log.debug("重新生成accessToken开始");
try {
String url = ApiUrl.GET_ACCESSTOKEN.replace("APPID", appID)
.replace("APPSECRET", appsecret);
log.debug("重新获取token的请求地址为:" + url);
URL urlGet = new URL(url);
HttpURLConnection http = (HttpURLConnection) urlGet
.openConnection(); http.setRequestMethod("GET");
http.setRequestProperty("Content-Type",
"application/x-www-form-urlencoded");
http.setDoOutput(true);
http.setDoInput(true);
System.setProperty("sun.net.client.defaultConnectTimeout", "30000");
System.setProperty("sun.net.client.defaultReadTimeout", "30000"); http.connect(); InputStream is = http.getInputStream();
int size = is.available();
byte[] jsonBytes = new byte[size];
is.read(jsonBytes);
String message = new String(jsonBytes, "UTF-8");
System.out.println("message:" + message);
JSONObject json = new JSONObject(message);
String access_token = json.getString("access_token");
Integer expiresIn = json.getInt("expires_in");
log.debug("重新生成accessToken结束 成功"); // 根据取得的accessToken 来获取jsapi_ticket
String ticketUrl = ApiUrl.GET_JSAPITICKET.replace("ACCESSTOKEN",
access_token);
log.debug("重新获取jsapi_ticket的请求地址为:" + ticketUrl);
URL ticketUrlGet = new URL(ticketUrl);
HttpURLConnection tickeHttp = (HttpURLConnection) ticketUrlGet
.openConnection(); tickeHttp.setRequestMethod("GET");
tickeHttp.setRequestProperty("Content-Type",
"application/x-www-form-urlencoded");
tickeHttp.setDoOutput(true);
tickeHttp.setDoInput(true);
System.setProperty("sun.net.client.defaultConnectTimeout", "30000");
System.setProperty("sun.net.client.defaultReadTimeout", "30000"); tickeHttp.connect(); InputStream tickeIs = tickeHttp.getInputStream();
byte[] tickeJsonBytes = new byte[tickeIs.available()];
tickeIs.read(tickeJsonBytes);
String tickeMessage = new String(tickeJsonBytes, "UTF-8");
System.out.println("message:" + message);
JSONObject ticketJson = new JSONObject(tickeMessage);
String ticket = ticketJson.getString("ticket"); AccessToken accessToken = new AccessToken();
accessToken.setAppId(appID);
accessToken.setSecret(appsecret);
accessToken.setAccessToken(access_token);
accessToken.setJsApiTicket(ticket);
accessToken.setExpireTime(DateUtil.getExpiresTime(expiresIn));
accessToken.setCreateTime(new Date());
weixinApiMapper.insertToken(accessToken);// 将新生成的token保存到数据库
} catch (Exception e) {
log.error("获取accessToken出错");
e.printStackTrace();
}
} @Override
public String createMenu() {
String access_token = getAccessToken();
String url = ApiUrl.CREATE_MENU.replace("ACCESSTOKEN", access_token);
log.debug("创建菜单的请求地址为:" + url);
try {
log.debug("menuString:" + menuString);
URL urlPost = new URL(url);
HttpURLConnection http = (HttpURLConnection) urlPost
.openConnection();
http.setRequestMethod("POST");
http.setRequestProperty("Content-Type",
"application/x-www-form-urlencoded");
http.setDoOutput(true);
http.setDoInput(true);
System.setProperty("sun.net.client.defaultConnectTimeout", "30000");
System.setProperty("sun.net.client.defaultReadTimeout", "30000"); http.connect();
OutputStream os = http.getOutputStream();
os.write(menuString.getBytes("UTF-8"));
os.flush();
os.close(); InputStream is = http.getInputStream();
int size = is.available();
byte[] jsonBytes = new byte[size];
is.read(jsonBytes);
String message = new String(jsonBytes, "UTF-8");
return message;
} catch (MalformedURLException e) {
e.printStackTrace();
return "-1";
} catch (IOException e) {
e.printStackTrace();
return "-1";
}
} @Override
public Map<String, String> getSignature(String url) {
Map<String, String> map = new HashMap<String, String>();
try {
String jsapi_ticket = getJsApiTicket();
String nonceStr = "Wm3WZYTPz0wzccnW";
long timestamp = System.currentTimeMillis() / 1000; map.put("appId", appID);
map.put("timestamp", timestamp + "");
map.put("nonceStr", nonceStr); String[] paramArr = new String[] { "jsapi_ticket=" + jsapi_ticket,
"timestamp=" + timestamp, "noncestr=" + nonceStr,
"url=" + url };
Arrays.sort(paramArr);
String content = paramArr[0].concat("&" + paramArr[1])
.concat("&" + paramArr[2]).concat("&" + paramArr[3]);
log.debug("拼接之后的content为:" + content);
MessageDigest md = MessageDigest.getInstance("SHA-1");
byte[] digest = md.digest(content.toString().getBytes());
String gensignature = CommonUtil.byteToStr(digest);
map.put("signature", gensignature);
return map;
} catch (Exception e) {
e.printStackTrace();
log.error("获取JSAPI签名信息失败,错误信息:" + e);
return null;
}
} @Override
public String getJsApiTicket() {
String jsApiTicket = null;
try {
AccessToken token = weixinApiMapper.findToken();// 数据库查找没过期的token并返回
if (token != null) {
jsApiTicket = token.getJsApiTicket();
}
} catch (Exception e) {
log.error("获取jsApiTicket出错");
e.printStackTrace();
}
log.debug("获取到的jsApiTicket是:" + jsApiTicket);
return jsApiTicket;
} }