Java 发送http请求（get、post）的示例
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2022-03-11 22:53:13
1.情景展示 java发送get请求、post请求（form表单、json数据）至另一服务器； 可设置http请求头部信息，可以接收服务器返回cookie信息，可以上传文件等；2.代码实现所需ja...
1.情景展示
java发送get请求、post请求（form表单、json数据）至另一服务器；
可设置http请求头部信息，可以接收服务器返回cookie信息，可以上传文件等；
2.代码实现
所需jar包：httpcore-4.4.1.jar；httpclient-4.4.1.jar；httpmime-4.4.1.jar；epoint-utils-9.3.3.jar
import java.io.file;
import java.io.ioexception;
import java.io.inputstream;
import java.nio.charset.charset;
import java.security.generalsecurityexception;
import java.security.cert.certificateexception;
import java.security.cert.x509certificate;
import java.util.arraylist;
import java.util.hashmap;
import java.util.list;
import java.util.map;
import javax.net.ssl.hostnameverifier;
import javax.net.ssl.sslcontext;
import javax.net.ssl.sslsession;
import org.apache.http.header;
import org.apache.http.httpentity;
import org.apache.http.httpresponse;
import org.apache.http.namevaluepair;
import org.apache.http.client.config.requestconfig;
import org.apache.http.client.entity.urlencodedformentity;
import org.apache.http.client.methods.closeablehttpresponse;
import org.apache.http.client.methods.httpdelete;
import org.apache.http.client.methods.httpentityenclosingrequestbase;
import org.apache.http.client.methods.httpget;
import org.apache.http.client.methods.httppatch;
import org.apache.http.client.methods.httppost;
import org.apache.http.client.methods.httprequestbase;
import org.apache.http.conn.ssl.sslconnectionsocketfactory;
import org.apache.http.conn.ssl.truststrategy;
import org.apache.http.entity.contenttype;
import org.apache.http.entity.stringentity;
import org.apache.http.entity.mime.multipartentitybuilder;
import org.apache.http.entity.mime.content.stringbody;
import org.apache.http.impl.client.closeablehttpclient;
import org.apache.http.impl.client.httpclients;
import org.apache.http.impl.conn.poolinghttpclientconnectionmanager;
import org.apache.http.message.basicnamevaluepair;
import org.apache.http.ssl.sslcontextbuilder;
import org.apache.http.util.entityutils;
import com.epoint.core.utils.string.stringutil;
/**
* httpclient工具类，使用http-client包实现，原先的common-httpclient已经淘汰
*
* @作者 ko
* @version [版本号, 2017年10月18日]
*/
public class httputil
{
private static poolinghttpclientconnectionmanager connmgr;
private static requestconfig requestconfig;
private static final int max_timeout = 7000;
/**
* 直接以流返回
*/
public static final int rtn_type_1 = 1;
/**
* 直接以string返回
*/
public static final int rtn_type_2 = 2;
/**
* 以map返回，reslut:接口结果string;statuscode:http状态码
*/
public static final int rtn_type_3 = 3;
/**
* 以map返回，reslut:接口结果string;statuscode:http状态码;cookie:response的cookie
* cookie值键值对，格式 key1=value1;key2=value2;...
*/
public static final int rtn_type_4 = 4;
/**
* 默认上传文件的文件流或file 的key name
*/
private static final string default_binarybody_keyname = "file";
static {
// 设置连接池
connmgr = new poolinghttpclientconnectionmanager();
// 设置连接池大小
connmgr.setmaxtotal(100);
connmgr.setdefaultmaxperroute(connmgr.getmaxtotal());
// 在提交请求之前 测试连接是否可用
connmgr.setvalidateafterinactivity(1);
requestconfig.builder configbuilder = requestconfig.custom();
// 设置连接超时
configbuilder.setconnecttimeout(max_timeout);
// 设置读取超时
configbuilder.setsockettimeout(max_timeout);
// 设置从连接池获取连接实例的超时
configbuilder.setconnectionrequesttimeout(max_timeout);
requestconfig = configbuilder.build();
}
/**
* 发送 get请求
*
* @param apiurl
* api接口url
* @return string 响应内容
*/
public static string doget(string apiurl) {
return dohttp(apiurl, null, "get", rtn_type_2);
}
/**
* 发送post请求
*
* @param apiurl
* api接口url
* @param params
* k-v参数
* @return string 响应内容
*/
public static string dopost(string apiurl, map<string, object> params) {
return dohttp(apiurl, params, "post", rtn_type_2);
}
/**
* 发送post请求
*
* @param apiurl
* api接口url
* @param json
* json参数
* @return string 响应内容
*/
public static string dopostjson(string apiurl, string json) {
return dohttp(apiurl, json, "post", rtn_type_2);
}
/**
* 发送 http 请求
*
* @param apiurl
* api接口url
* @param params
* {map<string, object> k-v形式、json字符串}
* @param method
* {null、或者post:post请求、patch:patch请求、delete:delete请求、get:get请求}
* @param type
* {httputil.rtn_type_1:请求返回stream(此时流需要在外部手动关闭);httputil.
* rtn_type_2:string;httputil.rtn_type_3:返回一个map,map包含结果(
* 结果是string形式)以及http状态码;httputil.rtn_type_4:返回一个map,map包含结果(
* 结果是string形式), http状态码和cookie;其他情况返回string}
* 如果结果是个map,key为:result,statuscode,cookie,分别返回 结果
* string,http状态码，cookie; cookie值键值对，格式
* key1=value1;key2=value2;...
* @return stream或 string 或 map
*/
public static <t> t dohttp(string apiurl, object params, string method, int type) {
return dohttp(apiurl, null, params, method, type);
}
/**
* 发送 http 请求
*
* @param apiurl
* api接口url
* @param headermap
* header信息map<string, string>,可设置cookie
* @param params
* {map<string, object> k-v形式、json字符串}
* @param method
* {null、或者post:post请求、patch:patch请求、delete:delete请求、get:get请求}
* @param type
* {httputil.rtn_type_1:请求返回stream(此时流需要在外部手动关闭);httputil.
* rtn_type_2:string;httputil.rtn_type_3:返回一个map,map包含结果(
* 结果是string形式)以及http状态码;httputil.rtn_type_4:返回一个map,map包含结果(
* 结果是string形式), http状态码和cookie;其他情况返回string}
* 如果结果是个map,key为:result,statuscode,cookie,分别返回 结果
* string,http状态码，cookie; cookie值键值对，格式
* key1=value1;key2=value2;...
* @return stream或 string 或 map
*/
public static <t> t dohttp(string apiurl, map<string, string> headermap, object params, string method, int type) {
closeablehttpclient httpclient = null;
if (isssl(apiurl)) {
httpclient = httpclients.custom().setsslsocketfactory(createsslconnsocketfactory())
.setconnectionmanager(connmgr).setdefaultrequestconfig(requestconfig).build();
}
else {
httpclient = httpclients.createdefault();
}
return dohttp(httpclient, apiurl, headermap, params, method, type);
}
/**
* 发送 http 请求
*
* @param httpclient
* httpclient对象 由外部传入，用户 需要保持登录状态等情况 此时如果要ssl,那么要在外部加入ssl特性
* httpclient =
* httpclients.custom().setsslsocketfactory(httputil.
* createsslconnsocketfactory())
* .setconnectionmanager(httputil.getconnmgr()).
* setdefaultrequestconfig(httputil..getrequestconfig()).build();
* @param apiurl
* api接口url
* @param headermap
* header信息map<string, string>,可设置cookie
*
* @param params
* {map<string, object> k-v形式、json字符串}
* @param method
* {null、或者post:post请求、patch:patch请求、delete:delete请求、get:get请求}
* @param type
* {httputil.rtn_type_1:请求返回stream(此时流需要在外部手动关闭);httputil.
* rtn_type_2:string;httputil.rtn_type_3:返回一个map,map包含结果(
* 结果是string形式)以及http状态码;httputil.rtn_type_4:返回一个map,map包含结果(
* 结果是string形式), http状态码和cookie;其他情况返回string}
* 如果结果是个map,key为:result,statuscode,cookie,分别返回 结果
* string,http状态码，cookie; cookie值键值对，格式
* key1=value1;key2=value2;...
* @return stream或 string 或 map
*/
@suppresswarnings("unchecked")
public static <t> t dohttp(closeablehttpclient httpclient, string apiurl, map<string, string> headermap,
object params, string method, int type) {
httprequestbase httppost = null;
if (stringutil.isnotblank(method)) {
if ("patch".equalsignorecase(method)) {
httppost = new httppatch(apiurl);
}
else if ("delete".equalsignorecase(method)) {
httppost = new httpdelete(apiurl);
}
else if ("get".equalsignorecase(method)) {
httppost = new httpget(apiurl);
}
else if ("post".equalsignorecase(method)) {
httppost = new httppost(apiurl);
}
}
else {
httppost = new httppost(apiurl);
}
closeablehttpresponse response = null;
try {
// 设置header信息
if (headermap != null && !headermap.isempty()) {
for (map.entry<string, string> entry : headermap.entryset()) {
httppost.addheader(entry.getkey(), entry.getvalue());
}
}
if (isssl(apiurl)) {
httppost.setconfig(requestconfig);
}
// 参数不为null、要处理参数
if (params != null) {
// get请求拼接在url后面
if (httppost instanceof httpget) {
stringbuffer param = new stringbuffer();
if (params instanceof map) {
map<string, object> paramsconvert = (map<string, object>) params;
int i = 0;
for (string key : paramsconvert.keyset()) {
if (i == 0)
param.append("?");
else
param.append("&");
param.append(key).append("=").append(paramsconvert.get(key));
i++;
}
}
else {
param.append("?" + params.tostring());
}
apiurl += param;
}
// delete请求暂不处理
else if (!(httppost instanceof httpdelete)) {
// k-v形式
if (params instanceof map) {
map<string, object> paramsconvert = (map<string, object>) params;
list<namevaluepair> pairlist = new arraylist<>(paramsconvert.size());
for (map.entry<string, object> entry : paramsconvert.entryset()) {
namevaluepair pair = new basicnamevaluepair(entry.getkey(),
entry.getvalue() == null ? "" : entry.getvalue().tostring());
pairlist.add(pair);
}
((httpentityenclosingrequestbase) httppost)
.setentity(new urlencodedformentity(pairlist, charset.forname("utf-8")));
}
// json格式
else {
stringentity stringentity = new stringentity(params.tostring(), "utf-8");
stringentity.setcontentencoding("utf-8");
stringentity.setcontenttype("application/json");
((httpentityenclosingrequestbase) httppost).setentity(stringentity);
}
}
}
response = httpclient.execute(httppost);
// int statuscode = response.getstatusline().getstatuscode();
// if (statuscode != httpstatus.sc_ok) {
// return null;
// }
httpentity entity = response.getentity();
if (entity != null) {
if (type == rtn_type_1) {
return (t) entity.getcontent();
}
else if (rtn_type_2 == type) {
return (t) entityutils.tostring(entity, "utf-8");
}
else if (rtn_type_3 == type || rtn_type_4 == type) {
map<string, string> rtnmap = new hashmap<string, string>();
rtnmap.put("result", entityutils.tostring(entity, "utf-8"));
rtnmap.put("statuscode", response.getstatusline().getstatuscode() + "");
if (rtn_type_4 == type) {
rtnmap.put("cookie", getcookie(response));
}
return (t) rtnmap;
}
else {
return (t) entityutils.tostring(entity, "utf-8");
}
}
}
catch (exception e) {
e.printstacktrace();
}
finally {
if (response != null && type != rtn_type_1) {
try {
entityutils.consume(response.getentity());
}
catch (ioexception e) {
e.printstacktrace();
}
}
}
return null;
}
/**
* 上传附件(post形式)
*
* @param url
* 请求地址
* @param headermap
* header参数map map<string, string>
* @param parammap
* 额外的参数map,map<string, string>
* @param file
* 可以选择本地文件上传；如果传了file，又传了filename，那么文件名以filename为准，否则 是file的文件名
* @param filename
* 以流传输时，必须指定文件名
* @param ssl
* 是否需要ssl
* @return result,返回上传结果，如果接口没有返回值，则为状态码
*/
public static string upload(string url, map<string, string> headermap, map<string, string> parammap, file file,
string filename, boolean ssl) {
return upload(url, headermap, parammap, file, null, filename, ssl);
}
/**
* 上传附件(post形式)
*
* @param url
* 请求地址
* @param headermap
* header参数map map<string, string>
* @param parammap
* 额外的参数map,map<string, string>
* @param in
* 文件流
* @param filename
* 以流传输时，必须指定文件名
* @param ssl
* 是否需要ssl
* @return result,返回上传结果，如果接口没有返回值，则为状态码
*/
public static string upload(string url, map<string, string> headermap, map<string, string> parammap, inputstream in,
string filename, boolean ssl) {
return upload(url, headermap, parammap, null, in, filename, ssl);
}
/**
* 上传附件(post形式)
*
* @param httpclient
* 外部传入httpclient
* @param url
* 请求地址
* @param headermap
* header参数map map<string, string>
* @param parammap
* 额外的参数map,map<string, string>
* @param file
* 可以选择本地文件上传；如果传了file，又传了filename，那么文件名以filename为准，否则 是file的文件名
* @param filename
* 以流传输时，必须指定文件名
* @param ssl
* 是否需要ssl
* @return result,返回上传结果，如果接口没有返回值，则为状态码
*/
public static string upload(closeablehttpclient httpclient, string url, map<string, string> headermap,
map<string, string> parammap, file file, string filename, boolean ssl) {
return upload(httpclient, url, headermap, parammap, file, null, filename, ssl);
}
/**
* 上传附件(post形式)
*
* @param httpclient
* 外部传入httpclient
* @param url
* 请求地址
* @param headermap
* header参数map map<string, string>
* @param parammap
* 额外的参数map,map<string, string>
* @param in
* 文件流
* @param filename
* 以流传输时，必须指定文件名
* @param ssl
* 是否需要ssl
* @return result,返回上传结果，如果接口没有返回值，则为状态码
*/
public static string upload(closeablehttpclient httpclient, string url, map<string, string> headermap,
map<string, string> parammap, inputstream in, string filename, boolean ssl) {
return upload(httpclient, url, headermap, parammap, null, in, filename, ssl);
}
/**
* 上传附件(post形式)
*
* @param url
* 请求地址
* @param headermap
* header参数map map<string, string>
* @param parammap
* 额外的参数map,map<string, string>
* @param file
* 可以选择本地文件上传，file,in互斥；如果传了file，又传了filename，那么文件名以filename为准，否则
* 是file的文件名
* @param in
* 文件流
* @param filename
* 以流传输时，必须指定文件名
* @param ssl
* 是否需要ssl
* @return result,返回上传结果，如果接口没有返回值，则为状态码
*/
private static string upload(string url, map<string, string> headermap, map<string, string> parammap, file file,
inputstream in, string filename, boolean ssl) {
closeablehttpclient httpclient = null;
if (ssl) {
httpclient = httpclients.custom().setsslsocketfactory(createsslconnsocketfactory())
.setconnectionmanager(connmgr).setdefaultrequestconfig(requestconfig).build();
}
else {
httpclient = httpclients.createdefault();
}
return upload(httpclient, url, headermap, parammap, file, in, filename, ssl);
}
/**
* 上传附件(post形式)
*
* @param httpclient
* 外部传入httpclient
* @param url
* 请求地址
* @param headermap
* header参数map map<string, string>
* @param parammap
* 额外的参数map,map<string, string>
* @param file
* 可以选择本地文件上传，file,in互斥；如果传了file，又传了filename，那么文件名以filename为准，否则
* 是file的文件名
* @param in
* 文件流
* @param filename
* 以流传输时，必须指定文件名
* @param ssl
* 是否需要ssl
* @return result,返回上传结果，如果接口没有返回值，则为状态码
*/
private static string upload(closeablehttpclient httpclient, string url, map<string, string> headermap,
map<string, string> parammap, file file, inputstream in, string filename, boolean ssl) {
string result = "";
closeablehttpresponse response = null;
try {
httppost httppost = new httppost(url);
// 设置header信息
if (headermap != null && !headermap.isempty()) {
for (map.entry<string, string> entry : headermap.entryset()) {
httppost.addheader(entry.getkey(), entry.getvalue());
}
}
if (ssl) {
httppost.setconfig(requestconfig);
}
multipartentitybuilder builder = multipartentitybuilder.create();
// 选择以file形式上传
if (file != null && file.exists()) {
if (stringutil.isnotblank(filename)) {
builder.addbinarybody(default_binarybody_keyname, file, contenttype.default_binary, filename);
}
else {
builder.addbinarybody(default_binarybody_keyname, file);
}
}
// 以流上传
else if (in != null && stringutil.isnotblank(filename)) {
builder.addbinarybody(default_binarybody_keyname, in, contenttype.default_binary, filename);
}
if (parammap != null && !parammap.isempty()) {
for (map.entry<string, string> entry : parammap.entryset()) {
builder.addpart(entry.getkey(), new stringbody(entry.getvalue(), contenttype.text_plain));
}
}
httpentity reqentity = builder.build();
httppost.setentity(reqentity);
response = httpclient.execute(httppost);
httpentity entity = response.getentity();
if (entity != null) {
result = entityutils.tostring(entity, "utf-8");
}
else {
result = response.getstatusline().getstatuscode() + "";
}
}
catch (exception e) {
e.printstacktrace();
}
finally {
if (response != null) {
try {
entityutils.consume(response.getentity());
}
catch (ioexception e) {
e.printstacktrace();
}
}
}
return result;
}
private static string getcookie(httpresponse httpresponse) {
map<string, string> cookiemap = new hashmap<string, string>(64);
header headers[] = httpresponse.getheaders("set-cookie");
if (headers == null || headers.length == 0) {
return null;
}
string cookie = "";
for (int i = 0; i < headers.length; i++) {
cookie += headers[i].getvalue();
if (i != headers.length - 1) {
cookie += ";";
}
}
string cookies[] = cookie.split(";");
for (string c : cookies) {
c = c.trim();
if (cookiemap.containskey(c.split("=")[0])) {
cookiemap.remove(c.split("=")[0]);
}
cookiemap.put(c.split("=")[0],
c.split("=").length == 1 ? "" : (c.split("=").length == 2 ? c.split("=")[1] : c.split("=", 2)[1]));
}
string cookiestmp = "";
for (string key : cookiemap.keyset()) {
cookiestmp += key + "=" + cookiemap.get(key) + ";";
}
return cookiestmp.substring(0, cookiestmp.length() - 2);
}
/**
* 创建ssl安全连接
*
* @return
*/
public static sslconnectionsocketfactory createsslconnsocketfactory() {
sslconnectionsocketfactory sslsf = null;
try {
sslcontext sslcontext = new sslcontextbuilder().loadtrustmaterial(null, new truststrategy()
{
public boolean istrusted(x509certificate[] chain, string authtype) throws certificateexception {
return true;
}
}).build();
sslsf = new sslconnectionsocketfactory(sslcontext, new hostnameverifier()
{
@override
public boolean verify(string arg0, sslsession arg1) {
return true;
}
});
}
catch (generalsecurityexception e) {
e.printstacktrace();
}
return sslsf;
}
public static poolinghttpclientconnectionmanager getconnmgr() {
return connmgr;
}
public static requestconfig getrequestconfig() {
return requestconfig;
}
private static boolean isssl(string apiurl) {
if (apiurl.indexof("https") != -1 ) {
return true;
}
else {
return false;
}
}
}
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