怎么在java中實現類似於python的requests模塊的session功能呢。java也是可以實現的,用java的okhttp包可以實現。
在pom.xml中加入相關依賴
<!-- https://mvnrepository.com/artifact/com.squareup.okhttp3/okhttp -->
<dependency>
<groupId>com.squareup.okhttp3</groupId>
<artifactId>okhttp</artifactId>
<version>4.2.2</version>
</dependency>
后面是相關的java代碼:
package com.puple.atto.datastructure;
import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Set;
import java.util.regex.*;
import okhttp3.Cookie;
import okhttp3.CookieJar;
import okhttp3.FormBody;
import okhttp3.HttpUrl;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
public class Session {
private final OkHttpClient mOkHttpClient = new OkHttpClient.Builder().cookieJar(new CookieJarManager()).build();
// //如果直接寫個類,里面寫saveFromResponse和loadForRequest,而不實現CookieJar接口,運行可以正常通過,但ide會顯紅,因為Bulider類的cookieJsr方法需要接受CookieJar類型的實例。鴨子類除了能節約代碼行數,在可理解性 可讀性 多人合作性上面都不如接口規范,誰知道鴨子類里面要寫什么方法,除了寫代碼得人自己。
private class CookieJarManager implements CookieJar{
private final HashMap<String, List<Cookie>> cookieStore = new HashMap<>();
@Override
public void saveFromResponse(HttpUrl url, List<Cookie> cookies) {
cookieStore.put(url.host(), cookies);
}
@Override
public List<Cookie> loadForRequest(HttpUrl url) {
List<Cookie> cookies = cookieStore.get(url.host());
return cookies != null ? cookies : new ArrayList<Cookie>(){};
}
}
/**
* @param url 要請求的url
* @param paramsMap post的請求參數
* @return post的返回結果
*/
public String post(String url, HashMap<String, String > paramsMap){
FormBody.Builder formBodyBuilder = new FormBody.Builder();
Set<String> keySet = paramsMap.keySet();
for(String key:keySet) {
String value = paramsMap.get(key);
formBodyBuilder.add(key,value);
}
FormBody formBody = formBodyBuilder.build();
Request request = new Request
.Builder()
.post(formBody)
.url(url)
.build();
try (Response response = mOkHttpClient.newCall(request).execute()) {
String respStr = response.body().string();
return respStr;
}catch (Exception e){
e.printStackTrace();
return "";
}
}
public String get(String url) {
final Request.Builder builder = new Request.Builder();
builder.url(url);
final Request request = builder.build();
try (Response response = mOkHttpClient.newCall(request).execute()) {
return response.body().string();
}catch (Exception e){
e.printStackTrace();
return "";
}
}
public static void test(){
Session ss=new Session();
String loginUrl="http://192.168.9.244:8080/RDCJWeb/login";
HashMap<String,String> paramsMap = new HashMap<>() ;
paramsMap.put("username","soft1");
paramsMap.put("password","soft1");
String respStr = ss.post(loginUrl,paramsMap);
String res=ss.get("http://192.168.9.244:8080/RDCJWeb/static/dist/html/deviceWarn.html");
System.out.println(res);
}
public static void main(String[] args) {
test();
}
}
