本篇使用Geocoding API逆地址解析经纬度，并且通过fastjson获取地址。
Geocoding API
Geocoding API 是一类接口，用于提供从地址到经纬度坐标或者从经纬度坐标到地址的转换服务，用户可以使用C# 、C++、Java等开发语言发送请求且接收JSON、XML的返回数据。
http://lbsyun.baidu.com/index.php?title=webapi/guide/webservice-geocoding
简单的说就是通过向http://api.map.baidu.com/geocoder/v2/发送一个HTTP/HTTPS请求然后获取返回的数据。
请求示例：
http://api.map.baidu.com/geocoder/v2/?callback=renderReverse&location=39.915,116.404&output=json&pois=1&ak=你的ak密钥
Tips:ak密钥需要登录百度账号申请。
JavaScipt调用
由于ajax跨域问题这里使用了dataType: 'JSONP'。
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
</head>
<body>
<button>提交</button>
</body>
<script type="text/javascript" src="js/jquery-1.9.1.js"></script>
<script>
$(document).ready(function() {
$("button").click(function() {
$.ajax({
type: "GET",
url: "http://api.map.baidu.com/geocoder/v2/?callback=renderReverse&location=39.915,116.404&output=json&pois=1&ak=你的ak密钥",
dataType: 'JSONP',
success: function(data) {
var list = data.result.addressComponent;
console.log(data);
console.log(list.country+""+list.province+""+list.district+""+list.street);
}
})
});
});
</script>
</html>
output:
Java调用
这里使用fastjson来解析。
package HttpRequest;
// 导入`fastjson`
import com.alibaba.fastjson.JSONObject;
// 封装的`HttpRequest`类
import HttpRequest.HttpRequest;
public class BaiduMapRequset {
public static void main(String[] args) {
String responseData = HttpRequest.sendGet("http://api.map.baidu.com/geocoder/v2/",
"callback=renderReverse&location=39.915,116.404&output=json&pois=1&ak=你的ak密钥");
//解析返回的`Json`
int start = responseData.indexOf("(") + 1;
responseData = responseData.substring(start, responseData.lastIndexOf(")"));
//获取返回的`city`值
JSONObject jsonobject = new JSONObject(responseData);
System.out.println(jsonobject.parseObject(responseData).getJSONObject("result").getJSONObject("addressComponent").get("city"));
}
}
output:
北京市
由于返回的值为Gson:renderReverse&&renderReverse({"status":0, ...... "cityCode":131}}),所以需要简单的解析一下。
使用HttpClient封装请求
HttpClient是Apache Jakarta Common下的子项目，用来提供高效的、最新的、功能丰富的支持HTTP协议的客户端编程工具包。
Maven地址：
<!-- https://mvnrepository.com/artifact/org.apache.httpcomponents/httpclient -->
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpclient</artifactId>
<version>4.5.2</version>
</dependency>
package HttpClient;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;
import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.utils.URIBuilder;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
import com.alibaba.fastjson.JSONObject;
public class HttpClient {
public static void main(String[] args) throws IOException {
try {
CloseableHttpClient httpclient = HttpClients.createDefault();
URI uri;
uri = new URIBuilder()
.setScheme("http")
.setHost("api.map.baidu.com")
.setPath("/geocoder/v2/")
.setParameter("callback", "renderOption")
.setParameter("output", "json")
.setParameter("address", "惠山区")
.setParameter("ak", "ONYb7QVTnolEPPGQhBsX2jG2kX3ki9yq")
.build();
// 创建httpget.
HttpGet httpget = new HttpGet(uri);
CloseableHttpResponse response = httpclient.execute(httpget);
System.out.println(response);
try {
HttpEntity entity = response.getEntity();
System.out.println(entity);
if (entity != null) {
// 打印响应内容长度
System.out.println("Response content length: " + entity.getContentLength());
// 打印响应内容
System.out.println("Response content: " + EntityUtils.toString(entity));
}
} finally {
response.close();
}
} catch (URISyntaxException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}