http://www.cnblogs.com/chenying99/p/3735282.html
依赖
- httpclient-4.4.1.jar
- httpcore-4.4.1.jar
不要引错了包
import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
Get请求示例
CloseableHttpClient httpClient = HttpClients.createDefault();
HttpGet httpget = new HttpGet(url.toString());
CloseableHttpResponse httpresponse = httpClient.execute(httpget);
try {
HttpEntity entity = httpresponse.getEntity();
String responseBody = EntityUtils.toString(entity);
// responseBody 就是返回的内容
} catch (Exception e) {
e.printStackTrace();
} finally {
if(httpClient != null){
httpClient.close();
}
if(httpresponse != null){
httpresponse.close();
}
}
HTTP请求
HttpClient支持HTTP/1.1这个版本定义的所有Http方法：GET,HEAD,POST,PUT,DELETE,TRACE和OPTIONS。对于每一种http方法，HttpClient都定义了一个相应的类：HttpGet, HttpHead, HttpPost, HttpPut, HttpDelete, HttpTrace和HttpOpquertions。
HttpClient提供URIBuilder工具类来简化URIs的创建和修改过程。
URI uri = new URIBuilder()
.setScheme("http")
.setHost("www.google.com")
.setPath("/search")
.setParameter("q", "httpclient")
.setParameter("btnG", "Google Search")
.setParameter("aq", "f")
.setParameter("oq", "")
.build();
HttpGet httpget = new HttpGet(uri);
System.out.println(httpget.getURI());
//http://www.google.com/search?q=httpclient&btnG=Google+Search&aq=f&oq=
HTTP响应
HttpResponse response =
new BasicHttpResponse(HttpVersion.HTTP_1_1, HttpStatus.SC_OK, "OK");
HttpResponse response =
new BasicHttpResponse(HttpVersion.HTTP_1_1,
HttpStatus.SC_OK, "OK");
System.out.println(response.getProtocolVersion());
System.out.println(response.getStatusLine().getStatusCode());
System.out.println(response.getStatusLine().getReasonPhrase());
System.out.println(response.getStatusLine().toString());
结果
HTTP/1.1
200
OK
HTTP/1.1 200 OK
消息头
HttpResponse response = new BasicHttpResponse(HttpVersion.HTTP_1_1,
HttpStatus.SC_OK, "OK");
response.addHeader("Set-Cookie", "c1=a; path=/; domain=localhost");
response.addHeader("Set-Cookie", "c2=b; path=\"/\", c3=c; domain=\"localhost\"");
Header h1 = response.getFirstHeader("Set-Cookie");
System.out.println(h1);
Header h2 = response.getLastHeader("Set-Cookie");
System.out.println(h2);
Header[] hs = response.getHeaders("Set-Cookie");
System.out.println(hs.length);
结果
Set-Cookie: c1=a; path=/; domain=localhost
Set-Cookie: c2=b; path="/", c3=c; domain="localhost"
2
HeaderIterator也提供非常便捷的方式，将Http消息解析成单独的消息头元素。
HttpResponse response = new BasicHttpResponse(HttpVersion.HTTP_1_1,
HttpStatus.SC_OK, "OK");
response.addHeader("Set-Cookie",
"c1=a; path=/; domain=localhost");
response.addHeader("Set-Cookie",
"c2=b; path=\"/\", c3=c; domain=\"localhost\"");
HeaderElementIterator it = new BasicHeaderElementIterator(
response.headerIterator("Set-Cookie"));
while (it.hasNext()) {
HeaderElement elem = it.nextElement();
System.out.println(elem.getName() + " = " + elem.getValue());
NameValuePair[] params = elem.getParameters();
for (int i = 0; i < params.length; i++) {
System.out.println(" " + params[i]);
}
}
结果
c1 = a
path=/
domain=localhost
c2 = b
path=/
c3 = c
domain=localhost
