【171】JAVA8发送带有Body的HTTP GET请求

正常来讲，按照HTTP标准，GET请求事不能带有消息体BODY的。但是HTTP标准不是硬性规定，各个厂商可以根据自己的需求做成灵活的扩展。比如ES的搜索接口就要求客户端发送带有BODY的HTTP GET请求。

发送请求的代码分成两个类，接收返回数据的 StrResponse 和发起请求的工具栏 HttpUtils

StrResponse.java

import java.util.List;
import java.util.Map;


public class StrResponse {
    private int code = 200;
    private Map> headers = null;
    private String body = null;

    public Map> getHeaders() {
        return headers;
    }

    public String getBody() {
        return body;
    }

    public void setHeaders(Map> headers) {
        this.headers = headers;
    }

    public void setBody(String body) {
        this.body = body;
    }

    public int getCode() {
        return code;
    }

    public void setCode(int code) {
        this.code = code;
    }

    public String getHeaderStr (String key) {
        List list = this.headers.get(key);
        StringBuilder sb = new StringBuilder();
        for (String str : list) {
            sb.append(str);
        }
        return sb.toString();
    }

    public String getAllHeaderStr() {
        if (null == headers || headers.isEmpty()) {
            return "";
        }
        StringBuilder sb = new StringBuilder();
        for (String key : headers.keySet()) {
            List list = headers.get(key);
            sb.append(key + ":n");
            for (String str : list) {
                sb.append("    " + str + "n");
            }
        }
        return sb.toString();
    }

    @Override
    public String toString() {
        final StringBuffer sb = new StringBuffer("StrResponse{");
        sb.append("code=").append(code);
        sb.append(", headers=").append(headers);
        sb.append(", body='").append(body).append(''');
        sb.append('}');
        return sb.toString();
    }
}

HttpUtils.java

import java.util.Map;
import java.util.List;
import java.io.*;
import java.net.*;


public class HttpUtils
{
	public static StrResponse requestByte_responseStr(final String url, final String method, 
			final byte[] requestBody,final Map headerMap, String responseEncoding) {
        BufferedReader in = null;
        BufferedReader errorReader = null;
        HttpURLConnection connection = null;
        StrResponse strResponse = null;
        try {
            StringBuilder result = new StringBuilder();
            URL realUrl = new URL(url);
            // 打开和URL之间的连接
            connection = (HttpURLConnection) realUrl.openConnection();
            connection.setRequestMethod(method);
            // 请求内容的长度
            if (null != requestBody && requestBody.length > 0) {
                connection.setRequestProperty("Content-Length", String.valueOf(requestBody.length));
            }
            // 自定义请求头
            if (null != headerMap && false == headerMap.isEmpty()) {
                Set keySet = headerMap.keySet();
                for (String key : keySet) {
                    connection.setRequestProperty(key, headerMap.get(key));
                }
            }
            connection.setConnectTimeout(5000);
            connection.setReadTimeout(5000);
            // 把JSON作为字节流写入post请求的body中
            connection.setDoOutput(true);
            if (null != requestBody && requestBody.length > 0) {
                connection.getOutputStream().write(requestBody);
            }
            // 定义 BufferedReader输入流来读取URL的响应
            in = new BufferedReader(new InputStreamReader(
                    connection.getInputStream(), responseEncoding));
            String line;
            while ((line = in.readLine()) != null) {
                result.append(line).append("n");
            }
            strResponse = new StrResponse();
            strResponse.setCode(connection.getResponseCode());
            // 返回的header
            Map> map = connection.getHeaderFields();
            strResponse.setHeaders(map);
            // 返回的body
            String responseBody = result.toString();
            strResponse.setBody(responseBody);
        } catch (Exception e) {
            e.printStackTrace();
            try {
                if (null != connection) {
                    StringBuilder result = new StringBuilder();
                    // 定义 BufferedReader输入流来读取URL的响应
                    errorReader = new BufferedReader(new InputStreamReader(
                            connection.getErrorStream(), responseEncoding));
                    String line;
                    while ((line = errorReader.readLine()) != null) {
                        result.append(line).append("n");
                    }
                    strResponse = new StrResponse();
                    strResponse.setCode(connection.getResponseCode());
                    // 返回的header
                    Map> map = connection.getHeaderFields();
                    strResponse.setHeaders(map);
                    // 返回的body
                    String responseBody = result.toString();
                    strResponse.setBody(responseBody);
                }
            } catch (Exception e2) {
                e2.printStackTrace();
            }
        } finally {
            try {
                if (null != in) {
                    in.close();
                }
                if (null != errorReader) {
                    errorReader.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return strResponse;
    }

    public static StrResponse requestStr_responseStr(final String url, final String method, final String requestBody,
                                               final Map headerMap, final String encoding) {
        // 字符串转成字节流
        byte[] bodyBytes = null;
        try {
            if (requestBody != null) {
                bodyBytes = requestBody.getBytes(encoding);
            }
        } catch (UnsupportedEncodingException e) {
            throw new RuntimeException(e);
        }
        return requestByte_responseStr(url, method, bodyBytes, headerMap, encoding);
    }
}

使用方法

public class Main{
	public static void main(String[] args) {
		String url = "http://192.168.19.11:9200/yourindex/_search";
        String requestBody = "{" +
                ""query": {" +
                "    "bool": {" +
                "      "must": [" +
                "        {" +
                "          "term": {" +
                "            "areaName.keyword": "" + areaName + """ +
                "          }" +
                "        }," +
                "        {" +
                "          "term": {" +
                "            "date.keyword": "" + date+ """ +
                "          }" +
                "        }," +
                "        {" +
                "          "term": {"rytype.keyword": "root"}" +
                "        }" +
                "      ]" +
                "    }" +
                "    " +
                "  }" +
                "}";
        Map headerMap = new HashMap<>();
        headerMap.put("Content-Type", "application/json");
        headerMap.put("Referer", url);
        String encoding = "UTF-8";
        StrResponse strResponse = HttpUtils.requestStr_responseStr(url, "GET", requestBody, 
        		headerMap, encoding);
        String body = strResponse.getBody();
        logger.info(body);
	}
}