Java創建Http連接

import java.io.BufferedReader;

import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.URL;
import java.net.URLConnection;
import java.security.KeyManagementException;
import java.security.NoSuchAlgorithmException;
import java.security.cert.X509Certificate;
import java.util.List;
import java.util.Map;

import javax.net.ssl.HostnameVerifier;
import javax.net.ssl.HttpsURLConnection;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSession;
import javax.net.ssl.TrustManager;
import javax.net.ssl.X509TrustManager;

public class HttpRequestUtil {
/**
* 向指定URL發送GET方法的請求
*
* @param url
* 發送請求的URL
* @param param
* 請求參數，請求參數應該是 name1=value1&name2=value2 的形式。
* @return URL 所代表遠程資源的響應結果
*/
public static String sendGet(String url, String param) {
String result = "";
BufferedReader in = null;
try {
String urlNameString = url + "?" + param;
URL realUrl = new URL(urlNameString);
// 打開和URL之間的連接
URLConnection connection = realUrl.openConnection();
// 設置通用的請求屬性
connection.setRequestProperty("accept", "*/*");
connection.setRequestProperty("connection", "Keep-Alive");
connection.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
// 建立實際的連接
connection.connect();
// 獲取所有響應頭字段
Map<String, List<String>> map = connection.getHeaderFields();
// 遍歷所有的響應頭字段
for (String key : map.keySet()) {
System.out.println(key + "--->" + map.get(key));
}
// 定義 BufferedReader輸入流來讀取URL的響應
in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
String line;
while ((line = in.readLine()) != null) {
result += line;
}
} catch (Exception e) {
System.out.println("發送GET請求出現異常！" + e);
e.printStackTrace();
}
// 使用finally塊來關閉輸入流
finally {
try {
if (in != null) {
in.close();
}
} catch (Exception e2) {
e2.printStackTrace();
}
}
return result;
}

/**
* 向指定 URL 發送POST方法的請求
*
* @param url
* 發送請求的 URL
* @param param
* 請求參數，請求參數應該是 name1=value1&name2=value2 的形式。
* @return 所代表遠程資源的響應結果
*/
public static String sendHttpPost(String url, String param) {
PrintWriter out = null;
BufferedReader in = null;
String result = "";
try {
URL realUrl = new URL(url);
// 打開和URL之間的連接
URLConnection conn = realUrl.openConnection();
// 設置通用的請求屬性
conn.setRequestProperty("accept", "*/*");
conn.setRequestProperty("connection", "Keep-Alive");
conn.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
// 發送POST請求必須設置如下兩行
conn.setDoOutput(true);
conn.setDoInput(true);
// 獲取URLConnection對象對應的輸出流
out = new PrintWriter(conn.getOutputStream());
// 發送請求參數
out.print(param);
// flush輸出流的緩沖
out.flush();
// 定義BufferedReader輸入流來讀取URL的響應
in = new BufferedReader(new InputStreamReader(conn.getInputStream()));
String line;
while ((line = in.readLine()) != null) {
result += line;
}
} catch (Exception e) {
System.out.println("發送 POST 請求出現異常！" + e);
e.printStackTrace();
}
// 使用finally塊來關閉輸出流、輸入流
finally {
try {
if (out != null) {
out.close();
}
if (in != null) {
in.close();
}
} catch (IOException ex) {
ex.printStackTrace();
}
}
return result;
}

private static class TrustAnyTrustManager implements X509TrustManager {

public void checkClientTrusted(X509Certificate[] chain, String authType) {
}

public void checkServerTrusted(X509Certificate[] chain, String authType) {
}

public X509Certificate[] getAcceptedIssuers() {
return new X509Certificate[] {};
}
}

private static class TrustAnyHostnameVerifier implements HostnameVerifier {
public boolean verify(String hostname, SSLSession session) {
return true;
}
}

/**
* post方式請求服務器(https協議)
*
* @param url
* 請求地址
* @param content
* 參數
* @param charset
* 編碼
* @return
* @throws NoSuchAlgorithmException
* @throws KeyManagementException
* @throws IOException
*/
public static String sendHttpsPost(String url, String content, String charset) throws NoSuchAlgorithmException, KeyManagementException, IOException {
SSLContext sc = SSLContext.getInstance("SSL");
sc.init(null, new TrustManager[] { new TrustAnyTrustManager() }, new java.security.SecureRandom());

URL console = new URL(url);
HttpsURLConnection conn = (HttpsURLConnection) console.openConnection();
conn.setSSLSocketFactory(sc.getSocketFactory());
conn.setHostnameVerifier(new TrustAnyHostnameVerifier());
conn.setDoOutput(true);
conn.connect();
DataOutputStream out = new DataOutputStream(conn.getOutputStream());
out.write(content.getBytes(charset));
// 刷新、關閉
out.flush();
out.close();
InputStream is = conn.getInputStream();
if (is != null) {
ByteArrayOutputStream outStream = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int len = 0;
while ((len = is.read(buffer)) != -1) {
outStream.write(buffer, 0, len);
}
is.close();
return new String(outStream.toByteArray(),charset);
}
return null;
}
}