OkHttpClient 发送请求示例

import okhttp3.*;

import java.util.Map;

/**
 * 类名称:OkHttpClientUtil
 * 类描述: OkHttp 客户端
 */
public class OkHttpClientUtil {

    public static String postJSON(String url, Map<String, String> headersMap, String param) throws Exception {
        OkHttpClient okHttpClient = new OkHttpClient();

        headersMap.put("Content-Type", "application/json");
        // 创建Headers.Builder对象，并添加请求头
        Headers.Builder headersBuilder = new Headers.Builder();
        for (Map.Entry<String, String> entry : headersMap.entrySet()) {
            headersBuilder.add(entry.getKey(), entry.getValue());
        }

        Request request = new Request.Builder()
                .headers(headersBuilder.build())
                .url(url)
                .post(RequestBody.create(MediaType.parse("application/json; charset=utf-8"), param))
                .build();

        String result = okHttpClient.newCall(request).execute().body().string();
        return result;
    }

}